CBSH


Line plots across dimensions of each concept
Line plots across concepts
Tables

Table of contents



us-gaap:CommonStockValue

us-gaap:PreferredStockParOrStatedValuePerShare
us-gaap:SubsequentEventType

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesAuthorized
us-gaap:StatementClassOfStock
us-gaap:CommonStockSharesOutstanding
cbsh:IncomePerCommonShare
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding
cbsh:IncomePerCommonShare
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EarningsPerShareBasic
cbsh:IncomePerCommonShare

us-gaap:EarningsPerShareDiluted
cbsh:IncomePerCommonShare
dei:LegalEntity
us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:CapitalToRiskWeightedAssets
us-gaap:ConsolidatedEntities

us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:GainLossOnInvestments
us-gaap:StatementBusinessSegments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxesPaidNet

us-gaap:InterestExpense

us-gaap:InterestIncomeExpenseNet
us-gaap:StatementBusinessSegments

us-gaap:InterestPaidNet

us-gaap:NetIncomeLoss
cbsh:IncomePerCommonShare

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic
cbsh:IncomePerCommonShare
cbsh:IncomePerCommonShare
us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

us-gaap:OtherComprehensiveIncomeLossNetOfTax
cbsh:ComponentsOfOtherComprehensiveIncome
us-gaap:StatementEquityComponents

us-gaap:PreferredStockDividendsIncomeStatementImpact
cbsh:IncomePerCommonShare

us-gaap:ProfitLoss
us-gaap:StatementEquityComponents

us-gaap:Assets
us-gaap:ConsolidatedEntities

us-gaap:Liabilities
us-gaap:ConsolidatedEntities

us-gaap:LiabilitiesAndStockholdersEquity
us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquity
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneRiskBasedCapital
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:Cash
us-gaap:ConsolidatedEntities
us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:PropertyPlantAndEquipmentGross
us-gaap:PropertyPlantAndEquipmentByType

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AmortizationOfIntangibleAssets
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill
us-gaap:StatementBusinessSegments

us-gaap:IntangibleAssetsNetExcludingGoodwill
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsNet
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:IntangibleAssetsNetIncludingGoodwill

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:EquitySecuritiesFvNi
us-gaap:ConsolidatedEntities
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:OtherAssets
us-gaap:ConsolidatedEntities

us-gaap:TimeDepositMaturitiesYearOne

us-gaap:MinorityInterest

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapital

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
cbsh:ComponentsOfOtherComprehensiveIncome

us-gaap:TreasuryStockValue

us-gaap:MinorityInterest

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
cbsh:IncomePerCommonShare

us-gaap:ProfitLoss
us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensation

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquireInvestments

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxAssetsNet

us-gaap:UnrecognizedTaxBenefits

cbsh:AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss
us-gaap:FinancingReceivablePortfolioSegment
cbsh:AccruedInterestReceivableOnHeldForInvestmentLoansWriteOff

cbsh:BankCardTransactionFees

cbsh:CapitalizedInterestOrDividends
us-gaap:FairValueByAssetClass

cbsh:ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements
us-gaap:FairValueByAssetClass
us-gaap:IncomeStatementLocation

cbsh:Depositfeerevenue

cbsh:EffectOnInterestIncomeResultingFromModificationToCreditCardLoans
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow
us-gaap:FinancialInstrument
cbsh:FairValueAdjustmentsOtherSecurities
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:FairValueEstimatedMarketRatePercent

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion
us-gaap:FairValueByAssetClass

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities
us-gaap:FairValueByAssetClass
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple

cbsh:GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal
us-gaap:FairValueByAssetClass
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
cbsh:ImpairmentAndImpairmentReversalsOfIntangibleAssetsFiniteLived
cbsh:IncomePerCommonShare
cbsh:IncomeAllocatedToUnvestedRestrictedStockholders

cbsh:InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell

cbsh:InterestOnOtherBorrowings

cbsh:InvestmentSecuritiesCalled
us-gaap:FairValueByAssetClass

cbsh:LoanFeesAndSales

cbsh:LoansNonrecurringBasisGainsLosses

cbsh:MortgageServicingRightsNonrecurringBasisGainsLosses
cbsh:IncomePerCommonShare
cbsh:NetIncomeAvailableToCommonStockholdersExcludingIncomeAllocatedToUnvestedRestrictedStockholders

cbsh:NetIncreaseDecreaseInShortTermBorrowings

cbsh:NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits

cbsh:NonvestedShareAwardsForfeitedInPeriod

cbsh:NonvestedShareAwardsGrantedInPeriod

cbsh:NonvestedShareAwardsVestedInPeriod

cbsh:OriginationOfLoansHeldForSale
us-gaap:FinancialInstrument
cbsh:OtherSecuritiesGainOnSale

cbsh:Paymentsforstockvalueissuedundersharebasedcompensationplans

cbsh:PercentofRevenuenotinscopeofASC606
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:ProbabilityofFunding

cbsh:ProceedsFromSaleOfOtherSecurities

cbsh:Proceedsfromsaleofequitysecurities

cbsh:Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities

cbsh:PurchaseOfRiskParticipationAgreement
us-gaap:FairValueByAssetClass

cbsh:SaleOfRiskParticipationAgreement
us-gaap:FairValueByAssetClass

cbsh:SalesAndRepaymentsOfPrivateEquitySecurities
us-gaap:FairValueByAssetClass

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsVestedInPeriodWeightedAverageGrantDateFairValue

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue

cbsh:ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue

cbsh:SuppliesPostageAndCommunication

cbsh:TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements
us-gaap:IncomeStatementLocation

cbsh:Trustfeerevenue
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:UnobservableInputDiscountRate
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:UnobservableInputLoanServicingCostsDelinquentLoans
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:UnobservableInputLoanServicingCostsPerformingLoans
us-gaap:Range, us-gaap:FairValueByAssetClass
cbsh:UnobservableInputPrepaymentSpeed
us-gaap:FairValueByAssetClass
cbsh:UnobservableInputsLoanServicingCostsLoansInForeclosure

us-gaap:AccretionAmortizationOfDiscountsAndPremiumsInvestments

us-gaap:BrokerageCommissionsRevenue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CommonStockDividendsPerShareCashPaid
us-gaap:FinancialInstrument
us-gaap:DebtSecuritiesAvailableForSaleRealizedGain

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:DepreciationAmortizationAndAccretionNet
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred

us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents

us-gaap:DividendsPreferredStockCash
us-gaap:StatementEquityComponents

us-gaap:EquipmentExpense
us-gaap:FinancialInstrument
us-gaap:EquitySecuritiesFvNiRealizedGain
us-gaap:FinancialInstrument
us-gaap:EquitySecuritiesFvNiUnrealizedGainLoss

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
us-gaap:FairValueByAssetClass

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
us-gaap:FairValueByAssetClass
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableAccruedInterestWriteoff

us-gaap:FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableAllowanceForCreditLossesRecovery
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:GainLossOnDerivativeInstrumentsNetPretax
us-gaap:HedgingDesignation

us-gaap:GainLossOnSaleOfLoansAndLeases

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable

us-gaap:IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet

us-gaap:IncreaseDecreaseInInterestAndDividendsReceivable

us-gaap:IncreaseDecreaseInInterestPayableNet

us-gaap:IncreaseDecreaseInTimeDeposits

us-gaap:IncreaseDecreaseInTradingSecurities
cbsh:IncomePerCommonShare
us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InformationTechnologyAndDataProcessing

us-gaap:InterestAndDividendIncomeOperating

us-gaap:InterestAndDividendIncomeSecurities

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldForSale

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio

us-gaap:InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase

us-gaap:InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits

us-gaap:InterestExpenseTimeDeposits100000OrMore

us-gaap:InterestExpenseTimeDepositsLessThan100000

us-gaap:InterestIncomeDepositsWithFinancialInstitutions

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss

us-gaap:InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell

us-gaap:LaborAndRelatedExpense

us-gaap:LeaseIncome

us-gaap:MarketingExpense

us-gaap:NoninterestExpense
us-gaap:StatementBusinessSegments

us-gaap:NoninterestIncome
cbsh:NatureofRevenue
cbsh:NatureofRevenue, us-gaap:ProductOrService
us-gaap:StatementBusinessSegments

us-gaap:NoninterestIncomeOther

us-gaap:NoninterestIncomeOtherOperatingIncome

us-gaap:OccupancyNet

us-gaap:OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:OperatingLeaseLeaseIncome
cbsh:OperatingLeaseIncome

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax
cbsh:ComponentsOfOtherComprehensiveIncome

us-gaap:OtherComprehensiveIncomeLossBeforeTax
cbsh:ComponentsOfOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax
us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax
us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseAdjustmentsBeforeTax
us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:OtherComprehensiveIncomeLossDerivativeExcludedComponentIncreaseDecreaseBeforeAdjustmentsAndTax
us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax
us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeLossTax
cbsh:ComponentsOfOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax
us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherNoninterestExpense

us-gaap:PaymentsForProceedsFromLoansAndLeases

us-gaap:PaymentsForRepurchaseOfRedeemablePreferredStock

us-gaap:PaymentsOfDividendsPreferredStockAndPreferenceStock

us-gaap:PreferredStockDividendsPerShareCashPaid

us-gaap:PreferredStockRedemptionPremium

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

us-gaap:ProceedsFromSaleOfAvailableForSaleSecurities

us-gaap:ProceedsFromSaleOfLoansHeldForSale

us-gaap:ProceedsFromSaleOfPropertyPlantAndEquipment

us-gaap:ProvisionForLoanAndLeaseLosses
us-gaap:StatementBusinessSegments

us-gaap:ProvisionForLoanLossesExpensed
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax
cbsh:ComponentsOfOtherComprehensiveIncome

us-gaap:SalesTypeAndDirectFinancingLeasesProfitLoss
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:ServicingAssetAtFairValueAdditions

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation
us-gaap:StatementEquityComponents

us-gaap:StockRedeemedOrCalledDuringPeriodValue
us-gaap:StatementEquityComponents

us-gaap:TransferToOtherRealEstate

us-gaap:TreasuryStockValueAcquiredCostMethod
us-gaap:StatementEquityComponents

cbsh:Aggregateamountoftimeopenandcertificatesofdepositthatexceedthe250000FDICinsurancelimit
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
cbsh:AssetsFairValueFinancialInstruments
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel
cbsh:AuctionRateSecuritiesAvailableForSale

cbsh:AvailableForSaleSecuritiesGrossUnreailzedGainatPeriodEnd
us-gaap:FinancialInstrument

cbsh:AvailableForSaleSecuritiesGrossUnrealizedLossatPeriodEnd
us-gaap:FinancialInstrument

cbsh:AverageAssets
us-gaap:StatementBusinessSegments

cbsh:AverageLoanPortfolioIncludingHeldForSale
us-gaap:StatementBusinessSegments
us-gaap:ConsolidatedEntities
cbsh:BanksInvestmentInConsolidatedSubsidiaries
cbsh:InterestRateFloorName, us-gaap:DerivativeInstrumentRisk, us-gaap:SubsequentEventType
cbsh:CashFlowHedgeGainLossReclassifiedIntoOCIBeforeTax
us-gaap:DerivativeInstrumentRisk, us-gaap:SubsequentEventType

cbsh:CashHeldatFederalReserveBank

cbsh:CertificatesOfDepositOver100000

cbsh:CertificatesOfDepositUnder100000
us-gaap:DerivativeInstrumentRisk
cbsh:CollateralAcceptedAggregateFairValue
us-gaap:Collateral, us-gaap:FinancingReceivablePortfolioSegment
cbsh:CollateralDependentLoansAmortizedCost
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:Collateral, us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
cbsh:CollateralDependentLoansBusinessAmortizedCost
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:Collateral, us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
cbsh:CollateralDependentLoansBusinessRealEstateAmortizedCost
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:DerivativeInstrumentRisk
cbsh:CollateralSwapAgreements

cbsh:CommercialLettersOfCredit
us-gaap:FinancialInstrument
cbsh:CommitmentToExtendCredit
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
cbsh:Commonstocks
us-gaap:RetirementPlanType

cbsh:ConsumerHealthcareLoansExcluded

cbsh:ContractualMaturitiesCertificatesOfDepositOver100000AfterTwelveMonths

cbsh:ContractualMaturitiesCertificatesOfDepositOver100000SixMonthsThroughTwelveMonths

cbsh:ContractualMaturitiesCertificatesOfDepositOver100000ThreeMonthsOrLess

cbsh:ContractualMaturitiesCertificatesOfDepositOver100000ThreeMonthsThroughSixMonths

cbsh:ContractualMaturitiesCertificatesOfDepositUnder100000AfterTwelveMonths

cbsh:ContractualMaturitiesCertificatesOfDepositUnder100000SixMonthsThroughTwelveMonths

cbsh:ContractualMaturitiesCertificatesOfDepositUnder100000ThreeMonthsOrLess

cbsh:ContractualMaturitiesCertificatesOfDepositUnder100000ThreeMonthsThroughSixMonths

cbsh:ContractualMaturitiesTimeDepositsAfterTwelveMonthsNet

cbsh:ContractualMaturitiesTimeDepositsSixMonthsThroughTwelveMonthsNet

cbsh:ContractualMaturitiesTimeDepositsThreeMonthsOrLessNet

cbsh:ContractualMaturitiesTimeDepositsThreeMonthsThroughSixMonthsNet
us-gaap:ProductOrService
cbsh:ContractwithCustomerReceivable
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
cbsh:CorporateBonds
us-gaap:RetirementPlanType

cbsh:CreditQualityPersonalBankingLoanTablePercentageLoansExcluded

cbsh:CreditQualityPersonalRealEstateLoansExcluded
us-gaap:Range
cbsh:CreditSupportInputVariable

cbsh:CumulativeEmployerContributionsInExcessOfNetPeriodicBenefitCost

cbsh:Deferredtaxassetsunearnedincome

cbsh:DefinedBenefitPlanAmountRecognizedInNetPeriodicPensionCostAndOtherComprehensiveIncome

cbsh:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationAssumedCreditOnCashBalanceAccounts
us-gaap:FinancialInstrument
cbsh:DerivatveAssetFairValueOfCollateral
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
cbsh:EmergingMarketSecurities
us-gaap:RetirementPlanType

cbsh:EqutiySecuritieswithoutReadilyDeterminableFairValues
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
cbsh:FairValuePlanAssets
us-gaap:RetirementPlanType

cbsh:FairValueSecuritiesOnImpairmentWatchList

cbsh:FairValueSecuritiesOnOtherThanTemporaryImpairmentWatchList

cbsh:FederalHomeLoanBankLettersOfCreditIssued

cbsh:FinancialInstrumentsOwnedAgencyMortgageBackedSecuritiesAtFairValue
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType

cbsh:FinancialInstrumentsOwnedNonAgencyMortgageBackedSecuritiesAtFairValue
us-gaap:ConsolidatedEntities
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType

cbsh:FinancialInstrumentsOwnedOtherDebtSecuritiesAtFairValue
us-gaap:FairValueByFairValueHierarchyLevel

cbsh:FinancingReceivableAllowanceForCreditLossAndUnfundedLendingCommitmentsTotal
us-gaap:FinancingReceivablePortfolioSegment

cbsh:FinancingReceivableRecordedInvestmentCurrentorLessthan30daysPastDue
cbsh:FinancingReceivableAndAllowanceInformationByPortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable

cbsh:FinancingReceivableRecordedInvestmentThirtyToEightyNineDaysPastDue
cbsh:FinancingReceivableAndAllowanceInformationByPortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable

cbsh:FinancingReceivableTroubledDebtRestructuringsThatSubsequentlyDefaultedRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
cbsh:GoodwillAndIntangibleAssetsNet
us-gaap:IndefiniteLivedIntangibleAssetsByMajorClass
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
cbsh:InternationalDevelopedMarketSecurities
us-gaap:RetirementPlanType

cbsh:InvestmentSecuritiesPledgedAtFairValue

cbsh:LessorTotalPaymentstobeReceived

cbsh:LessorTotalPaymentstobeReceivedFiveYears

cbsh:LessorTotalPaymentstobeReceivedFourYears

cbsh:LessorTotalPaymentstobeReceivedNextTwelveMonths

cbsh:LessorTotalPaymentstobeReceivedThereafter

cbsh:LessorTotalPaymentstobeReceivedThreeYears

cbsh:LessorTotalPaymentstobeReceivedTwoYears

cbsh:LettersOfCreditToCustomersWithRestructuredLoans

cbsh:LettersOfCreditToCustomersWithSubstandardRiskRating
us-gaap:RelatedPartyTransactionsByRelatedParty
cbsh:LineofCreditAvailableBorrowingCapacity

cbsh:LoansNonrecurringBasis
us-gaap:FairValueByFairValueHierarchyLevel

cbsh:LongLivedAssetsNonrecurringBasis
us-gaap:FairValueByFairValueHierarchyLevel

cbsh:LongTermSecuritiesPurchasedUnderAgreementsToResell
us-gaap:Range
cbsh:LossSeverityInputVariable

cbsh:MortgageServicingRightsNonrecurringBasis
us-gaap:FairValueByFairValueHierarchyLevel
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cbsh:Mutualfunds
us-gaap:RetirementPlanType
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cbsh:NonBanksInvestmentInConsolidatedSubsidiaries

cbsh:NonvestedShareAwardsBalances

cbsh:NumberOfLocations

cbsh:OtherAssetBackedSecuritiesDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType

cbsh:OtherSecurities
us-gaap:DerivativeInstrumentRisk
cbsh:Premiumpaidforinterestratefloorcashflowhedge
us-gaap:Range
cbsh:PrepaymentCprInputVariable

cbsh:PrivateEquityInvestments
us-gaap:Range
cbsh:ProjectedCumulativeDefaultInputVariable

cbsh:SalestypeandDirectFinancingLeasesUnguaranteedResidualAsset
us-gaap:FinancialInstrument
cbsh:SecuritiesPurchasedUnderAgreementsToResellNet
us-gaap:FinancialInstrument
cbsh:SecuritiesSoldUnderAgreementsToRepurchaseNet

cbsh:SegmentReportingInformationAverageDeposits
us-gaap:StatementBusinessSegments

cbsh:SegmentReportingInformationAverageGoodwillAndOtherIntangibleAssets
us-gaap:StatementBusinessSegments

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsWeightedAverageGrantDateUnitFairValue

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNumber

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesAndStockAppreciationRightsExercisesInPeriodTotalIntrinsicValue
us-gaap:ShortTermDebtType
cbsh:ShortTermBorrowingsActivityForYearAverageInterestRateAtPeriodEnd

cbsh:Shorttermrepurchaseagreementcomprisedofnoninsuredcustomerfunds

cbsh:StockAppreciationRightsActivityNumberOfSharesExercisable

cbsh:StockAppreciationRightsAggregateIntrinsicValueOptionsExercisable

cbsh:StockAppreciationRightsWeightedAverageExercisePriceStockOptionsExercisable

cbsh:StudentLoansHeldforSaleLowerofCostorFairValue
us-gaap:ConsolidatedEntities
cbsh:TaxAssets

cbsh:TaxBenefitRealizedFromOptionsAndStockAppreciationRightsExercised
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapital
us-gaap:ConsolidatedEntities
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapitalRequiredforCommonCapitalAdequacy
us-gaap:ConsolidatedEntities
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapitalRequiredforCommonCapitalAdequacytoRiskWeightedAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapitalRequiredtobeWellCapitalized
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapitalRequiredtobeWellCapitalizedtoRiskWeightedAssets
dei:LegalEntity
cbsh:TierOneRiskBasedCommonCapitaltoRIskWeightedAssets
us-gaap:ConsolidatedEntities

cbsh:TotalInvestmentSecurities

cbsh:USGovernmentSponsoredEnterprisesDebtSecurities
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:FinancialInstrument
cbsh:USTreasuryInflationProtectedSecuritiesHeld

cbsh:UnfundedLoanCommitments

cbsh:UnpaidPrincipalBalanceonPersonalRealEstateLoansHeldforSale

cbsh:UnusedApprovedCreditCardLinesOfCredit
us-gaap:DerivativeInstrumentRisk
cbsh:VariationMarginImpacttoNegativeFairValuesofClearedSwaps
us-gaap:DerivativeInstrumentRisk
cbsh:VariationMarginImpacttoPositiveFairValuesofClearedSwaps

dei:EntityCommonStockSharesOutstanding
us-gaap:ConsolidatedEntities
us-gaap:AdvancesToAffiliate

us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
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us-gaap:AssetsSoldUnderAgreementsToRepurchaseMaturityPeriods, us-gaap:FinancialInstrument
us-gaap:AssetsSoldUnderAgreementsToRepurchaseRepurchaseLiability

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis
cbsh:InvestmentMaturity, us-gaap:FinancialInstrument
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss

us-gaap:AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue

us-gaap:AvailableForSaleSecuritiesDebtSecurities
cbsh:InvestmentMaturity, us-gaap:FinancialInstrument
us-gaap:FinancialInstrument
dei:LegalEntity
us-gaap:Capital
us-gaap:ConsolidatedEntities

us-gaap:CapitalLeasesNetInvestmentInSalesTypeLeasesDeferredIncome
dei:LegalEntity
us-gaap:CapitalRequiredForCapitalAdequacy
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:CapitalRequiredToBeWellCapitalized
dei:LegalEntity
us-gaap:CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets

us-gaap:CashAndDueFromBanks
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:DerivativeInstrumentRisk
us-gaap:CollateralAlreadyPostedAggregateFairValue
us-gaap:ProductOrService
us-gaap:ContractWithCustomerReceivableAfterAllowanceForCreditLoss

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DeferredCompensationLiabilityCurrentAndNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:DeferredCompensationPlanAssets
us-gaap:FairValueByFairValueHierarchyLevel
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us-gaap:FairValueByMeasurementBasis

us-gaap:DeferredCostsLeasingNet

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities

us-gaap:DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses

us-gaap:DeferredTaxLiabilitiesDerivatives

us-gaap:DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets

us-gaap:DeferredTaxLiabilitiesLeasingArrangements

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOtherComprehensiveIncome

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

us-gaap:DefinedBenefitPlanAmountsRecognizedInBalanceSheet

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

us-gaap:DefinedBenefitPlanBenefitObligation

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets

us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:Deposits

us-gaap:DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement
us-gaap:FinancialInstrument
us-gaap:DerivativeAssetNotOffsetPolicyElectionDeduction
us-gaap:FinancialInstrument
us-gaap:DerivativeAssetNotSubjectToMasterNettingArrangement

us-gaap:DerivativeAssets
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:HedgingDesignation
us-gaap:FinancialInstrument
us-gaap:DerivativeAssetsNoncurrent
us-gaap:FinancialInstrument
us-gaap:DerivativeFairValueOfDerivativeAsset
us-gaap:FinancialInstrument
us-gaap:DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral
us-gaap:FinancialInstrument
us-gaap:DerivativeFairValueOfDerivativeLiability
us-gaap:FinancialInstrument
us-gaap:DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeFloorInterestRate

us-gaap:DerivativeLiabilities
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk, us-gaap:GuaranteeObligationsByNature
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:HedgingDesignation
us-gaap:FinancialInstrument
us-gaap:DerivativeLiabilitiesNoncurrent

us-gaap:DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement
us-gaap:FinancialInstrument
us-gaap:DerivativeLiabilityFairValueOfCollateral
us-gaap:FinancialInstrument
us-gaap:DerivativeLiabilityNotOffsetPolicyElectionDeduction
us-gaap:FinancialInstrument
us-gaap:DerivativeLiabilityNotSubjectToMasterNettingArrangement

us-gaap:DerivativeNotionalAmount
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk, us-gaap:GuaranteeObligationsByNature
us-gaap:PurchaseCommitmentExcludingLongtermCommitment

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized

us-gaap:EquityMethodInvestments

us-gaap:EquitySecuritiesFvNiAndWithoutReadilyDeterminableFairValue
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities
us-gaap:EquitySecuritiesWithoutReadilyDeterminableFairValueAmount

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
us-gaap:FairValueByAssetClass

us-gaap:FederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FederalFundsPurchasedFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FederalFundsSold
us-gaap:FairValueByMeasurementBasis

us-gaap:FederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell

us-gaap:FederalHomeLoanBankStock

us-gaap:FederalReserveBankStock

us-gaap:FinancialInstrumentsOwnedAndPledgedAsCollateralAmountEligibleToBeRepledgedByCounterparty

us-gaap:FinancialInstrumentsOwnedPrincipalInvestmentsAtFairValue
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FinancialInstrumentsOwnedStateAndMunicipalGovernmentObligationsAtFairValue
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType

us-gaap:FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FinancialLiabilitiesFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:FinancingReceivableAllowanceForCreditLosses
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableModificationsRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:LoanRestructuringModificationName
us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivableNonaccrualNoAllowance
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedFiveOrMoreYearsBeforeLatestFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedFourYearsBeforeLatestFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedInCurrentFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedInFiscalYearBeforeLatestFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedThreeYearsBeforeLatestFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableOriginatedTwoYearsBeforeLatestFiscalYear
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment

us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing
cbsh:FinancingReceivableAndAllowanceInformationByPortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus
cbsh:FinancingReceivableAndAllowanceInformationByPortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivableRevolving
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree

us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsCurrentCarryingValue
us-gaap:LossContingenciesByNatureOfContingency
us-gaap:PurchaseCommitmentExcludingLongtermCommitment
us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsMaximumExposure
us-gaap:LossContingenciesByNatureOfContingency

us-gaap:InterestBearingDepositLiabilities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:InterestBearingDepositsInBanks
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:DerivativeInstrumentRisk
us-gaap:InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet

us-gaap:InterestReceivable

us-gaap:InterestReceivableCurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:InvestmentsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceived

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFiveYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedFourYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThereafter

us-gaap:LessorOperatingLeasePaymentsToBeReceivedThreeYears

us-gaap:LessorOperatingLeasePaymentsToBeReceivedTwoYears

us-gaap:LiabilitiesFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:LineOfCredit
us-gaap:ConsolidatedEntities
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity

us-gaap:LoansAndLeasesReceivableAllowance

us-gaap:LoansAndLeasesReceivableGrossCarryingAmount
us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable

us-gaap:LoansAndLeasesReceivableImpairedCommitmentToLend

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome

us-gaap:LoansAndLeasesReceivableNetReportedAmount

us-gaap:LoansAndLeasesReceivableRelatedParties

us-gaap:LoansHeldForSaleFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:LoansReceivableFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable

us-gaap:LoansReceivableHeldForSaleAmount

us-gaap:MortgagesHeldForSaleFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:NetInvestmentInDirectFinancingAndSalesTypeLeases

us-gaap:NetInvestmentInLease

us-gaap:NoninterestBearingDepositLiabilities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:NotesReceivableGross
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivableRecordedInvestmentByClassOfFinancingReceivable, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment

us-gaap:OffBalanceSheetCreditLossLiability
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent

us-gaap:OtherBorrowings
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:OtherForeclosedAssets

us-gaap:OtherLiabilities
us-gaap:ConsolidatedEntities

us-gaap:PledgedFinancialInstrumentsNotSeparatelyReportedLoansReceivablePledgedForFederalHomeLoanBankDebt
us-gaap:ConsolidatedEntities
us-gaap:PostemploymentBenefitsLiabilityCurrentAndNoncurrent

us-gaap:PreferredStockLiquidationPreference

us-gaap:PreferredStockRedemptionPricePerShare

us-gaap:PropertySubjectToOrAvailableForOperatingLeaseNet
us-gaap:PurchaseCommitmentExcludingLongtermCommitment
us-gaap:PurchaseCommitmentRemainingMinimumAmountCommitted

us-gaap:RealEstateAcquiredThroughForeclosure

us-gaap:RestrictedCashAndCashEquivalents

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivable

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceived

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFiveYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedFourYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedNextTwelveMonths

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThereafter

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedThreeYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivablePaymentsToBeReceivedTwoYears

us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:SecuritiesLoanedOrSoldUnderAgreementsToRepurchaseFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:SecuritiesPurchasedUnderAgreementsToResell
us-gaap:FairValueByMeasurementBasis
us-gaap:FinancialInstrument
us-gaap:FinancialInstrument
us-gaap:SecuritiesPurchasedUnderAgreementsToResellCollateralObligationToReturnSecurities
us-gaap:FinancialInstrument
us-gaap:SecuritiesPurchasedUnderAgreementsToResellGross
us-gaap:FinancialInstrument
us-gaap:SecuritiesPurchasedUnderAgreementsToResellLiability
us-gaap:FinancialInstrument
us-gaap:SecuritiesSoldUnderAgreementsToRepurchase
us-gaap:FinancialInstrument
us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseAsset
us-gaap:FinancialInstrument
us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseCollateralRightToReclaimSecurities
us-gaap:FinancialInstrument
us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseGross

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
us-gaap:PlanName
us-gaap:PlanName
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAveragePriceOfSharesPurchased

us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueOutstanding
us-gaap:ShortTermDebtType
us-gaap:ShortTermBorrowings

us-gaap:StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased
dei:LegalEntity
us-gaap:TierOneLeverageCapital
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalRequiredForCapitalAdequacy
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalized

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
dei:LegalEntity
dei:LegalEntity
us-gaap:TierOneLeverageCapitalToAverageAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneRiskBasedCapitalRequiredForCapitalAdequacy
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneRiskBasedCapitalRequiredToBeWellCapitalized
dei:LegalEntity
us-gaap:TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets

us-gaap:TimeDepositMaturitiesAfterYearFive

us-gaap:TimeDepositMaturitiesYearFive

us-gaap:TimeDepositMaturitiesYearFour

us-gaap:TimeDepositMaturitiesYearThree

us-gaap:TimeDepositMaturitiesYearTwo

us-gaap:TimeDeposits
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:TimeDeposits100000OrMore

us-gaap:TimeDepositsLessThan100000

us-gaap:TradingSecurities
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:TreasuryStockShares

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount

us-gaap:ValuationAllowancesAndReservesBalance
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Interest Expense
Balance Sheet
Intangible Assets Net Excluding Goodwill
Assets
Operating Lease Right Of Use Asset
Current Assets
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents
NonCurrent Assets
Intangible Assets Net Excluding Goodwill
PropertyPlantAndEquipmentNet
Property Plant And Equipment Net
Liabilities
Derivative Liabilities
Stockholders Equity
Treasury Stock Value
Per Share
Common Stock Dividends Per Share Cash Paid
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Share Based Compensation
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Payments For Repurchase Of Common Stock
DividendsAndRepurchase
Payments For Repurchase Of Common Stock
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
FiniteLivedIntangibleAssets
Finite Lived Intangible Assets Net
BanksAndOrInsurance
Interest And Dividend Income Operating
AssetsBanks
Federal Funds Sold And Securities Purchased Under Agreements To Resell
LiabilitiesBanks
Deposits

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:CommonStockValue ███▇▇▇▇▇▇▇▇▆▆▆▆▄▄▄▄▄▄▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▂▂▂▁▁▁▁589.352589.352589.352563.978563.978563.978563.978559.432559.432559.432559.432535.407535.407535.407535.407510.015510.015510.015510.015489.862489.862489.862489.862484.155484.155484.155484.155481.224481.224481.224481.224459.647458.646458.646458.646446.387446.387446.387446.387436.481436.481436.043433.942NANANA
us-gaap:PreferredStockParOrStatedValuePerShare NANA1e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-060.01e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-061e-06NANANA
 us-gaap:PreferredStockParOrStatedValuePerShare us-gaap:SubsequentEventType us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:CommonStockSharesIssued ██████████▁▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆117.870372117.870372117.870372112.795605112.795605112.795605112.795605111.88645111.88645111.8864511.88645107.081397107.081397107.081397107.081397102.003046102.003046102.003046102.00304697.97243397.97243397.97243397.97243396.83097796.83097796.83097796.83097796.24476296.24476296.24476296.24476291.92948191.72923591.72923591.72923589.27739889.27739889.27739889.27739887.29628487.29628487.20865586.788322NANANA
us-gaap:CommonStockSharesAuthorized █████████▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▁▁▁▁▁▁▁▁▁▁▁▁▁▁140.0140.0140.0140.0140.0140.0140.0140.0140.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0120.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0NANANA
 us-gaap:CommonStockSharesOutstanding us-gaap:StatementClassOfStock us-gaap:CommonStockNANA117.138NANANA112.132NANANA111.129NANANA106.615NANANA101.461NANANA97.226NANANA96.327NANANA95.881NANANA91.414NANANA88.952NANANA86.624NANANA
 us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding cbsh:IncomePerCommonShare cbsh:DilutedIncomePerCommonShare▁█116.45116.573NA110.899110.897111.376NA107.856109.752110.301NA105.962106.029105.966NA100.934100.899100.767NA95.66995.63195.782NA92.26994.70295.588NA90.96893.91395.194NA90.45290.15990.444NA91.55292.05692.984NANANANANANANANA
 us-gaap:WeightedAverageNumberOfSharesOutstandingBasic cbsh:IncomePerCommonShare cbsh:BasicIncomePerCommonShare▁█116.163116.26NA110.72110.707111.118NA107.602109.487110.011NA105.608105.686105.634NA100.598100.555100.37NA95.42695.38295.566NA91.98994.3895.289NA90.57593.52994.773NA90.00389.78490.211NA91.23991.77492.632NANANANANANANANA
 us-gaap:WeightedAverageNumberOfSharesOutstandingBasic cbsh:IncomePerCommonShare cbsh:DilutedIncomePerCommonShare▁█116.163116.26NA110.72110.707111.118NA107.602109.487110.011NA105.609105.686105.634NA100.598100.555100.37NA95.42695.38295.566NA91.98994.3895.289NA90.57593.52994.773NA90.00389.78490.211NA91.23991.77492.632NANANANANANANANA
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount █▁0.0720.052NA0.3940.3110.229NA0.360.380.282NA0.092NA0.264NANANA0.086NANANA0.468NANANA0.307NANANA0.09NANANA0.0NANANA0.0NANANANANANANANA
us-gaap:EarningsPerShareBasic █▆▆▆▁▂▄▅▅▄▄▆▆▅▄▃▄▃▃▃▃▃▂▃▄▃▂▄▃▃▃▄▄▃▃▄▄▄▃▄▄▃▄▃▃▂1.381.121.01000000000000021.120.340.440.79999999999999980.980.960.850.81999999999999981.031.020.920.75999999999999980.710.750.680.58000000000000010.690.70.650.53000000000000020.670.750.610.53000000000000020.720.70.670.58999999999999990.750.720.670.62000000000000010.750.80.740.58000000000000010.760.80.690.720.630.690.5
 us-gaap:EarningsPerShareBasic cbsh:IncomePerCommonShare cbsh:BasicIncomePerCommonShare█▆▆▆▁▂▄▅▅▄▄▆▆▅▄▃▄▃▃▃▃▃▂▃▄▃▂▄▃▃▃▄▄▃▃▃▄▃1.381.121.01000000000000021.120.340.440.79999999999999980.980.960.850.81999999999999981.031.020.920.75999999999999980.710.750.680.58000000000000010.690.70.650.53000000000000020.670.750.610.53000000000000020.720.70.670.58999999999999990.750.720.670.58999999999999990.710.770.7NANANANANANANANA
us-gaap:EarningsPerShareDiluted █▆▆▆▁▂▄▅▅▄▄▆▆▅▄▃▄▃▃▃▃▃▂▃▄▃▂▄▃▃▃▄▄▃▃▄▄▄▃▄▄▃▃▃▃▂1.381.111.02000000000000021.110.340.440.790.980.960.850.81999999999999981.031.010.920.750.710.750.680.58000000000000010.680.70.650.540.660.750.610.520.720.70.670.58000000000000010.750.720.670.60999999999999990.750.80.740.57999999999999960.760.790.690.70.640.680.5
 us-gaap:EarningsPerShareDiluted cbsh:IncomePerCommonShare cbsh:DilutedIncomePerCommonShare█▆▆▆▁▂▄▅▅▄▄▆▆▅▄▃▄▃▃▃▃▃▂▃▄▃▂▄▃▃▃▄▄▃▃▄▄▃1.381.111.02000000000000021.110.340.440.790.980.960.850.81999999999999981.031.010.920.750.710.750.680.58000000000000010.680.70.650.540.660.750.610.520.720.70.670.58000000000000010.750.720.670.57999999999999960.720.760.7NANANANANANANANA
 us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets dei:LegalEntity cbsh:CommerceBankNANA1.219e-05NANANA1.237e-07NANANA1.314e-07NANANA1.192e-07NANANA1.1169999999999999e-07NANANA1.121e-07NANANA1.213e-07NANANA1.243e-07NANANA1.235e-07NANANA1.2939999999999998e-07NANANA1.278e-07NANANA
 us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets us-gaap:ConsolidatedEntities us-gaap:ConsolidatedEntitiesNANA1.3710000000000001e-05NANANA1.466e-07NANANA1.4979999999999998e-07NANANA1.341e-07NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CapitalToRiskWeightedAssets dei:LegalEntity cbsh:CommerceBankNANA1.3300000000000001e-05NANANA1.3189999999999998e-07NANANA1.398e-07NANANA1.276e-07NANANA1.2e-07NANANA1.207e-07NANANA1.316e-07NANANA1.3550000000000002e-07NANANA1.36e-07NANANA1.419e-07NANANA1.403e-07NANANA
 us-gaap:CapitalToRiskWeightedAssets us-gaap:ConsolidatedEntities us-gaap:ConsolidatedEntitiesNANA1.482e-05NANANA1.5479999999999998e-07NANANA1.582e-07NANANA1.4349999999999998e-07NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:AllocatedShareBasedCompensationExpense ██████▇▇▇▇▆▆▆▆▆▆▆▆▅▅▅▇▄▄▄▅▄▄▄▄▃▃▂▁▂▁▁▂▁▁▁▂▂▂▂3.83.93.73.83.73.73.53.53.43.53.23.23.13.33.03.03.13.12.62.62.93.42.42.42.52.72.22.22.22.31.81.91.51.21.31.21.11.41.11.21.11.31.31.31.5NA
us-gaap:ComprehensiveIncomeNetOfTax █▁▅▆▆▇▄▆█▇▇▄▅▃▃▅▅▅▁▄▅▆▃▄▃▅▄▃▅▅▄▄▁▄▃▅▅▂▂▃▃▂▁▃▃213.964-31.653117.831126.622135.988194.54973.151144.517204.888173.788186.57979.76191.11227.70141.40299.55590.61890.941-38.52855.203101.388135.83330.54481.45931.42590.67964.58744.102110.34695.08149.62172.385-42.09454.43637.09595.31489.4097.518-5.24332.78121.866-2.211-31.85919.40717.709NA
us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest █▆▆▅▂▁▄▅▄▃▅▅▅▅▄▃▄▄▄▄▃▄▄▄▅▅▅▅▃▃▃▄▄▃▃▄▄▅▅▄▄▄3.9232.2572.3070.907-1.132-2.2540.3980.8380.328-0.0831.1081.4930.9941.0770.628-0.3380.0290.1980.7950.605-0.0850.1480.7150.6010.970.9591.0170.836-0.631-0.192-0.090.2210.234-0.209-0.1880.780.5031.0151.5430.6570.5830.497NANANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest █▁▅▆▆▇▄▆█▇▇▄▅▃▃▅▅▅▁▄▅▆▃▄▃▅▄▃▅▅▃▄▁▄▃▅▅▄▄▅▅▄▃▄▄▄217.887-29.396120.138127.529134.856192.29573.549145.355205.216173.705187.68781.25492.10628.77842.0399.21790.64791.139-37.73355.808101.303135.98131.25982.0632.39591.63865.60444.938109.71594.88949.53172.606-41.8654.22736.90796.09489.91274.33257.80498.7991.48358.73930.36675.42877.52755.492
us-gaap:GainLossOnInvestments ▆▅▅▆▃▁▃▄▃▃▂▄▃▄█▃▄▃▄▃▃▃▃▃▄▄▄▄▃▅▃▃▃▃▃▄▄▄▄▄▄▄▄▃▃▃16.8049.85312.30716.155-4.129-13.301-0.2484.909-0.11-0.925-7.1294.306-3.0755.4127.209-3.0371.651-0.7723.651-1.965-0.744-0.995-1.48-0.3782.1436.0353.652.995-2.55810.037-1.3420.65-1.568-2.165-3.7283.181.3364.044.9422.5871.9561.3271.2040.0160.66-3.665
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments █▆▆▆▁▁▅▅▅▄▅▅▅▄▄▃▄▃▃▃▃▃▃▃▄▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▂▃▂211.458165.305165.28167.7348.39259.776135.492139.181137.198119.915137.297140.716140.831125.319115.087106.52112.1996.609104.671100.092101.3594.89292.08693.182107.81590.48292.899100.15996.21293.7396.184101.20996.22189.73394.23198.941105.70299.73492.56197.708102.30988.45786.65782.03387.24662.188
us-gaap:IncomeTaxExpenseBenefit █▅▆▆▁▁▅▅▅▄▄▄▅▄▃▅▆▄▅▅▅▅▅▅▅▅▅▅▅▅▅▆▅▅▅▅▆▆▅▅▆▅▄▄▄▃45.20932.07633.08434.3759.66110.17328.21429.10128.89922.8626.53726.64729.50723.25820.10432.29433.20124.90732.29730.94231.54229.3727.66127.96932.49228.46829.15731.13830.31229.60930.35932.76430.18228.92527.62832.15534.46632.9229.51431.69932.69227.50724.43226.01227.42818.377
us-gaap:IncomeTaxesPaidNet ▇▁▅▇▁▁▃▄▄▁▅▃▄▁▅▅▇▁▄▄▇▁▄▄▅▁▅▆▆▁▄▃█▁▃▅▇▂▄▄▇▁▄▅▅▁52.932.5131.31653.9173.6631.1722.00728.11924.6921.3538.0521.15324.8220.14733.29532.82851.7712.8531.06528.64557.2282.65824.48128.78339.1242.95334.1740.84845.961-0.80730.00518.87863.4222.03114.99139.37655.5289.27129.85822.13454.2060.45525.47236.95638.351-0.169
us-gaap:InterestExpense ▁▁▂▂▃▆▇██▇▆▅▄▄▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▃▃▃▃▃▄▄▄▅▆▆▇3.1513.9494.9637.15210.26620.4224.00628.23126.77824.37720.61216.99714.66413.10311.56411.65310.7879.7248.2968.1188.2368.3537.2557.0776.926.8446.9877.0957.0746.9327.2767.4387.7978.4028.9329.3839.51910.22911.46612.20513.37714.85316.75919.47921.94925.359
us-gaap:InterestIncomeExpenseNet ▇▇▇█▇▇▇▇█▇█▇▇▆▅▅▅▄▄▄▄▃▃▃▃▁▂▂▂▂▂▂▂▁▃▂▃▂▃▂▃▂▂▂▃▃207.982205.748209.763215.962203.057201.065202.659203.512211.634203.488212.22207.754210.959192.892190.008182.591182.807178.273173.202171.243171.829163.775162.487162.038163.657146.138151.929154.716160.493153.066154.865154.706159.458150.343161.253153.811165.105159.737161.757158.63164.71160.973160.677159.437163.108162.71
us-gaap:InterestPaidNet ▁▁▂▃▄▇▇█▇▆▆▄▄▄▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▃▃▃▃▄▅▄▆▆▇█4.1565.7536.7379.67613.25122.58124.35826.71425.06621.66819.16515.70614.53313.83511.30311.18411.5189.6857.4587.9068.4598.0736.8236.9737.1476.8176.947.3367.0736.8697.4768.5198.2818.1569.13710.2659.81810.11511.67113.91216.13214.78419.58922.28223.65727.48
us-gaap:NetIncomeLoss █▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▃▂▂▃▂▂▃▂▃▂▂▂▃▂▂▂▂▁162.326130.972129.889132.44839.86351.857106.88109.242107.97197.138109.652112.576110.33100.98494.35574.56478.9671.50471.57968.54569.89365.37463.7164.61274.35361.05562.72568.18566.53164.31365.91568.22465.80561.01766.79166.00670.73365.79961.50465.35269.03460.45361.92155.88559.73444.17
us-gaap:NetIncomeLossAttributableToNoncontrollingInterest █▆▆▅▂▁▄▅▄▃▅▅▅▅▄▃▄▄▄▄▃▄▄▄▅▅▅▅▃▃▃▄▄▃▃▄▄▅▅▄▄▄▄▄▄▃3.9232.2572.3070.907-1.132-2.2540.3980.8380.328-0.0831.1081.4930.9941.0770.628-0.3380.0290.1980.7950.605-0.0850.1480.7150.6010.970.9591.0170.836-0.631-0.192-0.090.2210.234-0.209-0.1880.780.5031.0151.5430.6570.5830.4970.3040.1360.084-0.359
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic █▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▃▂▃▃▃162.326130.972129.889124.98237.61349.607104.63106.992105.72194.888107.402110.326108.0898.73492.10572.31476.7169.25469.32966.29567.64363.12461.4662.36272.10358.80560.47566.38566.53164.31365.91568.22465.805NANANANANANANANANANANANANA
 us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted cbsh:IncomePerCommonShare cbsh:DilutedIncomePerCommonShare█▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▃▂▃▃▃162.326130.972129.889124.98237.61349.607104.63106.992105.72194.888107.402110.326108.0898.73492.10572.31476.7169.25469.32966.29567.64363.12461.4662.36272.10358.80560.47566.38566.53164.31365.91568.22465.805NANANANANANANANANANANANANA
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▆▁▄▅▇█▄▆▇▆▆▄▄▃▄▅▅▅▂▄▅▆▄▅▄▅▅▄▆▅▄▅▂▅▄▅▅▅51.638-162.625-12.058-5.82696.125142.692-33.72935.27596.91776.6576.927-32.815-19.218-73.283-52.95324.99111.65819.437-110.107-13.34231.49570.459-33.16616.847-42.92829.6241.862-24.08343.81530.768-16.2944.161-107.899-6.581-29.69629.30818.6767.518NANANANANANANANA
us-gaap:PreferredStockDividendsIncomeStatementImpact NANA0.07.4662.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.251.80.00.00.00.00.0NANANANANANANANANANANANANA
 us-gaap:PreferredStockDividendsIncomeStatementImpact cbsh:IncomePerCommonShare cbsh:BasicIncomePerCommonShareNANA0.07.4662.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.251.80.00.00.00.00.0NANANANANANANANANANANANANA
us-gaap:ProfitLoss █▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▂▂▂▃▂▂▃▃▃▃▂▂▃▂▂▂▂▁166.249133.229132.196133.35538.73149.603107.278110.08108.29997.055110.76114.069111.324102.06194.98374.22678.98971.70272.37469.1569.80865.52264.42565.21375.32362.01463.74269.02165.964.12165.82568.44566.03960.80866.60366.78671.23666.81463.04766.00969.61760.9562.22556.02159.81843.811
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:Assets ███▇▆▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃▃▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▁▁▁33856.16233269.78632922.97431453.81730496.12126793.01726065.78925876.47925772.17425033.47125463.84225062.39224524.74224611.24224833.41524979.14125078.84325308.17125641.42424734.46824709.69324506.95224604.96223967.64823705.93524049.48323994.2822701.54523005.17922837.1223072.03622452.29721910.35122227.20822159.58920878.76920742.99120526.91720649.36720638.66819570.8619017.29618502.339NANANA
us-gaap:Liabilities ███▇▆▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▁▁▁30362.33229952.40129523.00228147.55327137.95223540.55322927.31722770.46522600.81121990.25822526.69322254.58221753.35921905.51422115.23122274.66422450.63622744.60623140.29222173.65522182.87222059.6722237.54421596.60521390.57521644.07621660.03420412.67620743.02620563.60920857.63920270.81119803.56420048.01719988.01518571.69718512.22218327.71118479.00618508.70317439.29316946.80616478.875NANANA
us-gaap:LiabilitiesAndStockholdersEquity ███▇▆▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃▃▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▁▁▁33856.16233269.78632922.97431453.81730496.12126793.01726065.78925876.47925772.17425033.47125463.84225062.39224524.74224611.24224833.41524979.14125078.84325308.17125641.42424734.46824709.69324506.95224604.96223967.64823705.93524049.48323994.2822701.54523005.17922837.1223072.03622452.29721910.35122227.20822159.58920878.76920742.99120526.91720649.36720638.66819570.8619017.29618502.339NANANA
us-gaap:StockholdersEquity █▇█▇▇▇▆▆▆▆▅▅▅▄▄▄▄▄▃▄▃▃▃▃▂▃▂▂▂▂▂▂▁▂▂▂▂▂▂▂▂▁▁3485.623312.593397.0473305.6633357.8673251.0153134.6843102.63168.7313037.7552931.2982803.0932767.9872703.1222716.562700.5442623.8832558.7032495.7832555.4212521.9162442.0282361.992365.3052309.9212400.6142330.1932285.8312259.7752270.3792210.6422177.5332102.8272175.1452167.1272302.4362226.5512195.3362166.0472127.2142129.3682068.7222021.987NANANA
 us-gaap:TierOneRiskBasedCapital dei:LegalEntity cbsh:CommerceBankNANA2606.169NANANA2421.919NANANA2494.584NANANA2268.131NANANA2111.797NANANA1983.051NANANA1869.053NANANA1809.231NANANA1713.752NANANA1678.53NANANA1604.873NANANA
 us-gaap:TierOneRiskBasedCapital us-gaap:ConsolidatedEntities us-gaap:ConsolidatedEntitiesNANA2950.926NANANA2890.322NANANA2861.016NANANA2567.264NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 us-gaap:Cash us-gaap:ConsolidatedEntities srt:ParentCompanyNANA171.943NANANA301.913NANANA207.462NANANA151.607NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidatedEntities srt:ParentCompanyNANA171.943NANANA301.913NANANA207.462NANANA151.607NANANA0.051NANANA0.053NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents █▇▇▅▅▂▂▂▃▁▃▂▁▁▁▁▁▁▂2546.3362380.8242208.3281557.4761818.114899.514907.808884.38961.455606.4321209.24805.154547.591584.946524.352599.776545.379554.776801.641NANANA502.719NANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:PropertyPlantAndEquipmentGross NANA944.353NANANA923.097NANANA863.779NANANA852.072NANANA886.74NANANA897.111NANANA885.877NANANA863.314NANANA860.572NANANA841.987NANANA843.338NANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType cbsh:RightofuseleasedassetsNANA29.589NANANA28.195NANANA0.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:BuildingAndBuildingImprovementsNANA582.056NANANA566.177NANANA545.51NANANA540.204NANANA530.489NANANA541.736NANANA535.039NANANA529.842NANANA523.662NANANA517.691NANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:EquipmentNANA239.216NANANA237.047NANANA226.666NANANA216.876NANANA258.03NANANA250.193NANANA244.239NANANA227.467NANANA229.37NANANA223.548NANANANANANANA
 us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType us-gaap:LandNANA93.492NANANA91.678NANANA91.603NANANA94.992NANANA98.221NANANA105.182NANANA106.599NANANA106.005NANANA107.54NANANA100.748NANANANANANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment NANA573.27NANANA552.46NANANA530.66NANANA516.962NANANA549.035NANANA544.53NANANA528.006NANANA513.66NANANA502.96NANANA481.841NANANA459.941NANANA
us-gaap:AmortizationOfIntangibleAssets ▆█▆▇▃▁▂▂▂▂▂▂▁▂▁▂▂▂▁▂▂▂▂▃▃▃▃▃▄▄▄▃▄▄▄▄▅▅0.7450.9510.80.8590.4420.2680.40.3950.3730.3420.3480.3180.3130.3210.30.3380.330.3480.30.3740.3990.3950.40.4450.4720.4730.50.4990.5490.5590.60.4630.5320.5570.60.5940.6690.684NANANANANANANANA
us-gaap:PropertyPlantAndEquipmentNet ▆▆▆▇▆▆▆▆▅▅▁▁▁▁▁▁▁▁▂▂▂▄▄▄▄▄▅▄▃▃▃▄▄▄▅▃▄▄▅▆▇▇█371.989371.737371.083377.853368.565369.745370.637365.949363.554362.679333.119331.869331.782332.253335.11335.348334.586335.191337.705339.196342.237350.423352.581351.946353.366356.309357.871357.122346.363344.79349.654353.473352.462355.464357.612350.04350.897353.866360.146368.965374.732378.721383.397NANANA
us-gaap:Goodwill ████████████████████████████████▁▁▁▁▁▁▁▁▁▁▁138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.921138.676125.585125.585125.585125.585125.585125.585125.585125.585125.585125.585125.585NANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill █▇▆▃▃▄▅▄▄▄▄▄▄▃▃▃▃▃▃▃▂▂▃▃▃▃▃▃▄▄▄▄▁▁▂▂▂▃▃▄▅▅▆14.14813.09811.2077.1837.1798.4339.5349.1398.7638.5118.7948.478.0837.8937.6187.3887.0026.76.7096.6216.5616.5396.6696.8266.9787.1437.457.7718.2498.8119.2689.054.5174.875.35.8046.3817.077.7148.4529.39410.18210.937NANANA
us-gaap:FiniteLivedIntangibleAssetsNet █▆▁10.5489.4987.607NANANA9.534NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IntangibleAssetsNetIncludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass cbsh:MortgageServicingRights█▇▅▅▅▆▇▆▆▆▆▅▅▄▄▄▃▃▃▂▂▂▂▁▁▁▁9.3768.2346.2495.7315.6256.7687.7497.2356.736.3416.4786.0085.4635.1054.6534.2453.6463.1062.8682.5332.1911.8431.6381.4611.2420.9940.878NANANANANANANANANANANANANANANANANANANA
 us-gaap:IntangibleAssetsNetIncludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:CoreDeposits▁▁▁▁▁▂▂▂▂▂▂▃▃▃▃▄▄▄▄▅▅▆▆▆▇▇█1.1721.2641.3581.4521.5541.6651.7851.9042.0332.172.3162.4622.622.7882.9653.1433.3563.5943.8414.0884.374.6965.0315.3655.7366.1496.572NANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingLeaseRightOfUseAsset NANA28.3NANANA26.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:EquitySecuritiesFvNi █▂▂▁▁▁▂▂▁▁▁6.9812.9312.9662.8032.7112.6332.9292.9022.8472.8082.585NANANA48.838NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:TimeDepositMaturitiesYearOne NANA1627.852NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:MinorityInterest █▅▃▁▁▂▄▄▃▆▆▅▄▃▂▄▅▅▅▆▅▅▆▆▆▅▄▃▃▄▄▄▄▄▅▅▄▄▅▃▃▂▂8.214.7952.9250.6010.3021.4493.7883.4142.6325.4585.8514.7173.3962.6061.6243.9334.3244.8625.3495.3924.9055.2545.4285.7385.4394.7934.0533.0382.3783.1323.7553.9533.964.0464.4474.6364.2183.874.3142.7512.1991.7681.477NANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANA5.305NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA4.715NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANA3.454NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA2.025NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANA14.453NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:StockholdersEquity █▇█▇▇▇▆▆▆▆▅▅▅▄▄▄▄▄▃▄▃▃▃▃▂▃▂▂▂▂▂▂▁▂▂▂▂▂▂▂▂▁▁3485.623312.593397.0473305.6633357.8673251.0153134.6843102.63168.7313037.7552931.2982803.0932767.9872703.1222716.562700.5442623.8832558.7032495.7832555.4212521.9162442.0282361.992365.3052309.9212400.6142330.1932285.8312259.7752270.3792210.6422177.5332102.8272175.1452167.1272302.4362226.5512195.3362166.0472127.2142129.3682068.7222021.987NANANA
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest █▇█▇▇▇▆▆▇▆▆▅▅▄▅▄▄▄▄▄▄▃▃▃▃▃▃▃▂▃▂▂▂▂▂▃▂▂▂▂▂▂▁▂▁▁3493.833317.3853399.9723306.2643358.1693252.4643138.4723106.0143171.3633043.2132937.1492807.812771.3832705.7282718.1842704.4772628.2072563.5652501.1322560.8132526.8212447.2822367.4182371.0432315.362405.4072334.2462288.8692262.1532273.5112214.3972181.4862106.7872179.1912171.5742307.0722230.7692199.2062170.3612129.9652131.5672070.492023.4642046.6051988.6141927.435
us-gaap:CommonStockValue ███▇▇▇▇▇▇▇▇▆▆▆▆▄▄▄▄▄▄▄▄▃▃▃▃▃▃▃▃▂▂▂▂▂▂▂▂▁▁▁▁589.352589.352589.352563.978563.978563.978563.978559.432559.432559.432559.432535.407535.407535.407535.407510.015510.015510.015510.015489.862489.862489.862489.862484.155484.155484.155484.155481.224481.224481.224481.224459.647458.646458.646458.646446.387446.387446.387446.387436.481436.481436.043433.942NANANA
us-gaap:AdditionalPaidInCapital ███▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▁▁▁▁▁▁▁▁2424.1572420.3932436.2882140.412136.8742133.6232151.4642042.6432077.4912074.9122084.8241804.0311804.0571802.7851815.361548.3181546.5341544.0341552.4541335.151333.9951332.4291337.6771283.3461261.3071223.1251229.0751215.7321214.8361273.291279.9481104.6691094.9221101.4451102.5071033.5151033.5231032.9851042.065980.176979.247976.101971.293NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▄▂▁▄▃▃▂▅▄▄▃▆▅▄▃▅▄▄▃▆▅▅▄▆▆▅▅▇▆▆▅▇▆▆▅██▇▆█▇▇▆304.739173.17373.0326.89232.082224.643201.562463.231384.232307.193241.163493.641408.374325.39221.374440.261390.853337.046292.849515.081470.558424.677383.313555.877514.451463.701426.648583.49537.759492.559449.836610.72563.166517.792477.21717.138671.297620.78575.419690.981645.155596.177555.778NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▆▅███▇▅▅▅▃▂▁▁▂▃▄▄▃▃▅▅▄▃▄▄▄▄▄▄▄▃▃▃▅▅▅▅▅▅▅▄▄▄220.39168.752331.377343.435349.261253.136110.444144.173108.89811.981-64.669-141.596-108.781-89.56314.10867.06142.0730.41210.975121.082134.424102.92932.4765.63648.78991.71762.09360.23184.31440.4999.73126.02521.864129.763136.344166.04136.732118.056110.538115.78183.061.13463.345NANANA
us-gaap:TreasuryStockValue ▂▂▂▃▃▃▂█▄▃▂▂▁▁▁▁▁▁▁▂▂▂▂▆▅▁▁▇▇▁▁▂▂▂▁▃▃▂▁▄▁▁▁53.01839.0832.9769.0569.11269.14937.548251.663106.10660.54734.23633.17415.85415.68114.4739.89510.3737.58815.29450.53851.70752.65326.116168.493143.5656.86816.562199.63203.17417.19310.09723.52835.77132.5017.5860.64461.38822.8728.36296.20514.5150.7332.371NANANA
us-gaap:MinorityInterest █▅▃▁▁▂▄▄▃▆▆▅▄▃▂▄▅▅▅▆▅▅▆▆▆▅▄▃▃▄▄▄▄▄▅▅▄▄▅▃▃▂▂8.214.7952.9250.6010.3021.4493.7883.4142.6325.4585.8514.7173.3962.6061.6243.9334.3244.8625.3495.3924.9055.2545.4285.7385.4394.7934.0533.0382.3783.1323.7553.9533.964.0464.4474.6364.2183.874.3142.7512.1991.7681.477NANANA
us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue ▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▇▅▁▆█▅3.793.9333.6843.7653.7393.7293.4893.4863.3993.483.2863.1613.1043.292.9562.9543.063.1352.6242.6142.8763.4112.4452.452.5122.742.1982.1632.2072.2611.8221.8571.5251.2231.2961.151.1481.4071.1171.2423.628-1.256-10.691.2835.226-1.84
us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders ▃▃▂▃▂▂▂▂█▃▂▃▃▂▂▂▃▄▄▃▃▃▄▃▃▃▂▃▃▃▃▃▃▃▂▃▃▅▂▃▃▂▁▃▃▂0.5080.387-0.0170.6080.0150.0850.0240.0563.1540.31-0.0260.1720.2040.095-0.0120.0530.5670.6850.8380.1180.2640.3221.0250.3020.3240.2190.0020.1760.1230.4310.1080.2280.320.1920.0010.3620.1551.459-0.020.1050.564-0.206-0.7370.1370.42-0.185
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▄▆▅▇▅▄▅▄▄▅▄▅▅▅▄▄▃▅▄▃▄▆▂▄▄▄▃▄▄▄▃▄▃▄▄▄▄▄▄▄▄▄▇█▅▁125.58201.669151.609242.655149.9679.768135.46125.6109.553142.181105.949158.634144.088143.98998.916122.29270.713141.30586.255.2994.993195.88410.23585.26798.04495.51775.20776.77787.377121.47572.156120.87269.83498.07187.74691.97383.248120.14596.264116.22892.899101.97265.309311.138149.468-54.738
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆▅▄▁▆▆▆▇▇▇▆▇█▇▇█▇▅▇▇▇▆▆█▆▅█▆▇▆█▇▆▅▇▇▇▅▆▆▆▇▅▇█-368.432-327.731-947.561-1503.448-2657.901-281.594-275.902-306.233-116.708-31.32235.77-379.699-30.457283.362-100.479176.162318.415-173.378-712.4-110.913-65.42383.523-570.752-430.801406.615-600.464-852.32327.896-319.658-218.6-528.216207.53631.39-424.37-974.05826.253-218.3955.363-1114.077-403.595-250.073-417.09-112.653-867.298-41.125366.622
us-gaap:NetCashProvidedByUsedInFinancingActivities ▃▃▅▄█▃▂▂▃▁▃▃▂▂▂▂▂▂▄▂▂▂▃▂▂▂▄▂▂▁▄▃▂▂▄▂▃▂▄▂▃▃▂▃▃▁408.364298.5581446.8041000.1553426.541193.532163.87103.558362.178-713.667262.367478.628-150.986-366.757-86.368-229.805-396.601-211.762941.515-102.50539.471-225.919604.486102.935-355.581-43.4991155.373-247.09248.971-424.203776.55191.123-292.526167.2691096.776-59.53211.387-208.634965.684-30.088474.621424.133-112.893325.428189.905-422.322
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet ▅▄█▁▅▆▅▅▅▅▅▅▄▄▅▄▅▄▅▅▅▅▅▅▄▅▅▅▄▅▅▄▄▅▅▅▅▅▅▄▆▄▆▅▃▅17.81-11.178140.776-151.85118.25660.88114.4358.02932.81918.0820.9564.994-10.746-9.21215.071-10.49610.167-8.1822.06414.8176.4333.35210.8243.207-12.4849.6427.2850.662-11.2296.5246.224-7.46-14.3928.9360.0763.101-4.41912.0365.483-13.92337.253-26.34137.6964.143-61.96622.869
us-gaap:NetCashProvidedByUsedInOperatingActivities ▄▆▅▇▅▄▅▄▄▅▄▅▅▅▄▄▃▅▄▃▄▆▂▄▄▄▃▄▄▄▃▄▃▄▄▄▄▄▄▄▄▄▇█▅▁125.58201.669151.609242.655149.9679.768135.46125.6109.553142.181105.949158.634144.088143.98998.916122.29270.713141.30586.255.2994.993195.88410.23585.26798.04495.51775.20776.77787.377121.47572.156120.87269.83498.07187.74691.97383.248120.14596.264116.22892.899101.97265.309311.138149.468-54.738
us-gaap:NetIncomeLoss █▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▃▂▂▃▂▂▃▂▃▂▂▂▃▂▂▂▂▁162.326130.972129.889132.44839.86351.857106.88109.242107.97197.138109.652112.576110.33100.98494.35574.56478.9671.50471.57968.54569.89365.37463.7164.61274.35361.05562.72568.18566.53164.31365.91568.22465.80561.01766.79166.00670.73365.79961.50465.35269.03460.45361.92155.88559.73444.17
us-gaap:ProfitLoss █▆▆▆▁▂▅▅▅▄▅▅▅▄▄▃▃▃▃▃▃▂▂▂▃▂▂▃▂▂▂▃▂▂▃▃▃▃▂▂▃▂▂▂▂▁166.249133.229132.196133.35538.73149.603107.278110.08108.29997.055110.76114.069111.324102.06194.98374.22678.98971.70272.37469.1569.80865.52264.42565.21375.32362.01463.74269.02165.964.12165.82568.44566.03960.80866.60366.78671.23666.81463.04766.00969.61760.9562.22556.02159.81843.811
us-gaap:ShareBasedCompensation ██▇██▇▇▇▇▇▆▆▆▆▆▆▆▆▅▅▅▇▄▄▄▅▄▄▄▄▃▃▂▁▁▁▁▂▁▁▁▁▂▁▂▃3.793.9333.6843.7653.7373.7293.4893.4863.3993.483.2863.1613.1043.292.9562.9543.063.1352.6242.6142.8763.4112.4452.452.5122.742.1982.1632.2072.2611.8221.8571.5251.2231.2961.151.1481.4071.1171.2421.1161.2561.3521.2831.5461.84
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆▅▄▁▆▆▆▇▇▇▆▇█▇▇█▇▅▇▇▇▆▆█▆▅█▆▇▆█▇▆▅▇▇▇▅▆▆▆▇▅▇█-368.432-327.731-947.561-1503.448-2657.901-281.594-275.902-306.233-116.708-31.32235.77-379.699-30.457283.362-100.479176.162318.415-173.378-712.4-110.913-65.42383.523-570.752-430.801406.615-600.464-852.32327.896-319.658-218.6-528.216207.53631.39-424.37-974.05826.253-218.3955.363-1114.077-403.595-250.073-417.09-112.653-867.298-41.125366.622
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▅▄▁▆▂▃▅▄▄▅▅▃▃▂▃▃▃▂▂▂▂▃▄▃▃▃▄█▄▁▂▃▂▂▆▃▂▂▂▂▂▂▂▁▃▁11.21410.733.94215.5156.1037.57413.1349.1529.00611.28311.9367.8338.5434.9827.9718.7368.6615.4565.9994.836.267.3899.1797.1956.9488.5759.45319.62210.6293.9545.118.0184.8465.86715.7267.546.315.3935.1975.0025.3145.8195.3673.7666.6132.782
us-gaap:PaymentsToAcquireInvestments ▅▄▆█▇▂▂▂▂▂▂▃▂▂▃▂▁▂▃▃▁▁▄▃▂▄▄▁▂▃▃▁▂▃▄▂▃▂▅▄▄▃▃▄▃▂1512.1331194.8911856.2492487.1372078.995569.079556.573334.333539.629432.645570.098771.528450.153298.554781.035446.851143.289482.642908.098665.849233.38180.7741034.734796.826585.0081125.9691183.842117.292568.719628.237888.388213.385375.238934.1421146.597558.826918.783558.6511591.0181116.9441008.069801.432947.1221229.949735.03305.499
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▃▃▅▄█▃▂▂▃▁▃▃▂▂▂▂▂▂▄▂▂▂▃▂▂▂▄▂▂▁▄▃▂▂▄▂▃▂▄▂▃▃▂▃▃▁408.364298.5581446.8041000.1553426.541193.532163.87103.558362.178-713.667262.367478.628-150.986-366.757-86.368-229.805-396.601-211.762941.515-102.50539.471-225.919604.486102.935-355.581-43.4991155.373-247.09248.971-424.203776.55191.123-292.526167.2691096.776-59.53211.387-208.634965.684-30.088474.621424.133-112.893325.428189.905-422.322
us-gaap:PaymentsOfDividendsCommonStock ▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂█▂▃▁▂▂▂▂▂▂▂▂30.7630.79930.17830.17430.17430.29227.93327.99328.68228.85824.97725.05925.09625.10622.89722.90622.90322.91321.77621.77221.76221.7620.9220.93621.35321.75220.66620.65421.33121.5920.56820.6720.43120.435150.78920.16539.581.07419.50419.52620.05620.05419.39519.62119.61519.6
us-gaap:PaymentsForRepurchaseOfCommonStock ▃▄▃▃▃▄▃▄▄▄▄▄▃▃▃▃▃▃▃▃▃▄▃▁▅▃▃▃█▄▃▄▃▄▄▃▄▄▃▅▃▃▄▃▃▃13.96425.9230.4030.1670.44853.14514.93433.89146.3839.69935.65620.5062.00217.0676.4510.6923.3447.2840.9051.0141.0336.43214.029-74.42881.8571.7181.9340.051188.08920.90.15823.90315.29929.99329.3733.88440.05231.60.04382.7714.034.31139.9370.1040.0650.878
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value589589589563563563563559559559559535535535535510510510510489489489489484484484484481481481481459458458458446446446446436436436433415
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.71.81.81.81.82.12.22.22.22.22.22.12.22.22.22.02.02.02.02.02.02.02.02.02.02.02.02.12.12.12.12.02.12.12.12.12.22.22.22.12.22.32.32.3

Preferred Stock Par Or Stated Value Per Share

us-gaap:PreferredStockParOrStatedValuePerShare

us-gaap:PreferredStockParOrStatedValuePerShare


Preferred
Period End2020-12-312020-09-302020-09-012020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-06-192014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.001.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.0
Percentage of PreferredStockParOrStatedValuePerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PreferredStockParOrStatedValuePerShare us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


Preferred
Period End2020-07-31
Value1.0
Percentage of PreferredStockParOrStatedValuePerShare0.0

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1171171171121121121121111111111110710710710710210210210297979797969696969696969691919191898989898787878683
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

us-gaap:CommonStockSharesAuthorized

us-gaap:CommonStockSharesAuthorized


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-04-172019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value140140140140140140140140140140120120120120120120120120120120120120120120120120120120120120100100100100100100100100100100100100100100100
Percentage of CommonStockSharesAuthorized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding us-gaap:StatementClassOfStock

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStock


Common
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value1171121111061019796959188868375
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding cbsh:IncomePerCommonShare

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

cbsh:DilutedIncomePerCommonShare


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value116116110110111107109110105106105100100100959595929495909395909090919292
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic cbsh:IncomePerCommonShare

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

cbsh:BasicIncomePerCommonShare


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value116116110110111107109110105105105100100100959595919495909394908990919192
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:DilutedIncomePerCommonShare


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value116116110110111107109110105105105100100100959595919495909394908990919192
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount


Antidilutive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-03-312017-03-312016-03-312015-03-312014-03-312013-03-312012-03-31
Value72000.052000.0394000.0311000.0229000.0360000.0380000.0282000.092000.0264000.086000.0468000.0307000.090000.000
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.381.121.011.120.340.440.80.980.960.850.821.031.020.920.760.710.750.680.580.690.70.650.530.670.750.610.530.720.70.670.590.750.720.670.620.750.80.740.580.760.80.690.720.630.690.5
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EarningsPerShareBasic cbsh:IncomePerCommonShare

cbsh:BasicIncomePerCommonShare


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value1.381.121.011.120.340.440.80.980.960.850.821.031.020.920.760.710.750.680.580.690.70.650.530.670.750.610.530.720.70.670.590.750.720.670.590.710.770.7
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.095.294.796.294.6

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.381.111.021.110.340.440.790.980.960.850.821.031.010.920.750.710.750.680.580.680.70.650.540.660.750.610.520.720.70.670.580.750.720.670.610.750.80.740.580.760.790.690.70.640.680.5
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EarningsPerShareDiluted cbsh:IncomePerCommonShare

cbsh:DilutedIncomePerCommonShare


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value1.381.111.021.110.340.440.790.980.960.850.821.031.010.920.750.710.750.680.580.680.70.650.540.660.750.610.520.720.70.670.580.750.720.670.580.720.760.7
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.095.196.095.094.6

Tier One Risk Based Capital To Risk Weighted Assets

us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets dei:LegalEntity

us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets

cbsh:CommerceBank


Tier
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value12.190.12370.13140.11920.11170.11210.12130.12430.12350.12940.1278
Percentage of TierOneRiskBasedCapitalToRiskWeightedAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TierOneRiskBasedCapitalToRiskWeightedAssets us-gaap:ConsolidatedEntities

us-gaap:ConsolidatedEntities


Tier
Period End2020-12-312019-12-312018-12-312017-12-31
Value13.710.14660.14980.1341
Percentage of TierOneRiskBasedCapitalToRiskWeightedAssets112.5118.5114.0112.5

Capital To Risk Weighted Assets

us-gaap:CapitalToRiskWeightedAssets dei:LegalEntity

us-gaap:CapitalToRiskWeightedAssets

cbsh:CommerceBank


Capital
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value13.30.13190.13980.12760.120.12070.13160.13550.1360.14190.1403
Percentage of CapitalToRiskWeightedAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalToRiskWeightedAssets us-gaap:ConsolidatedEntities

us-gaap:ConsolidatedEntities


Capital
Period End2020-12-312019-12-312018-12-312017-12-31
Value14.820.15480.15820.1435
Percentage of CapitalToRiskWeightedAssets111.4117.4113.2112.5

Allocated Share Based Compensation Expense

us-gaap:AllocatedShareBasedCompensationExpense

us-gaap:AllocatedShareBasedCompensationExpense


Allocated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value3.83.93.73.83.73.73.53.53.43.53.23.23.13.33.03.03.13.12.62.62.93.42.42.42.52.72.22.22.22.31.81.91.51.21.31.21.11.41.11.21.11.31.31.31.5
Percentage of AllocatedShareBasedCompensationExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating1.81.91.71.71.71.71.51.51.41.51.41.41.41.61.51.51.61.61.41.41.62.01.41.41.51.81.41.41.31.41.11.20.90.80.80.70.60.80.60.70.60.70.70.70.8

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value213-31.6531171261351947314420417318679912741999090-38.52855101135308131906444110954972-42.094543795897.518-5.2433221-2.211-31.8591917
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating101.3-15.154.956.863.787.832.362.485.976.380.135.540.413.420.551.346.848.4-21.230.856.378.918.048.218.459.340.627.365.959.430.644.6-25.234.321.858.451.24.4-3.019.212.3-1.3-18.010.89.6

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3923000.02257000.02307000.0907000.0-1132000.0-2254000.0398000.0838000.0328000.0-83000.01108000.01493000.0994000.01077000.0628000.0-338000.029000.0198000.0795000.0605000.0-85000.0148000.0715000.0601000.0970000.0959000.01017000.0836000.0-631000.0-192000.0-90000.0221000.0234000.0-209000.0-188000.0780000.0503000.01015000.01543000.0657000.0583000.0497000.0
Percentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating1.91.11.10.4-0.5-1.00.20.40.1-0.00.50.70.40.50.3-0.20.00.10.40.3-0.00.10.40.40.60.60.60.5-0.4-0.1-0.10.10.1-0.1-0.10.50.30.60.90.40.30.3

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value217-29.3961201271341927314520517318781922842999091-37.73355101135318232916544109944972-41.8654369689745798915830757755
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating103.2-14.055.957.263.286.832.462.786.176.280.636.240.814.020.951.146.848.5-20.831.156.379.018.448.519.059.941.327.865.559.330.544.8-25.034.221.758.951.543.733.457.851.433.417.142.241.929.5

Gain Loss On Investments

us-gaap:GainLossOnInvestments

us-gaap:GainLossOnInvestments


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value169.8531216-4.129-13.301-0.2484.909-0.11-0.925-7.1294.306-3.0755.4127-3.0371.651-0.7723.651-1.965-0.744-0.995-1.48-0.3782.1436.0353.652.995-2.55810-1.3420.65-1.568-2.165-3.7283.181.3364.044.9422.5871.9561.3271.2040.0160.66-3.665
Percentage of GainLossOnInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating8.04.75.77.2-1.9-6.0-0.12.1-0.0-0.4-3.11.9-1.42.613.5-1.60.9-0.42.0-1.1-0.4-0.6-0.9-0.21.33.92.31.9-1.56.3-0.80.4-0.9-1.4-2.21.90.82.42.91.51.10.80.70.00.4-1.9

us-gaap:GainLossOnInvestments us-gaap:StatementBusinessSegments

cbsh:OtherElimination


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value169.8531216-4.129-13.301-0.2484.909-0.11-0.925-7.1294.306-3.0755.4127-3.0371.651-0.7723.651-1.965-0.744-0.995-1.48-0.3782.1436.0353.652.995-2.55810-1.3420.65-1.568
Percentage of GainLossOnInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating8.04.75.77.2-1.9-6.0-0.12.1-0.0-0.4-3.11.9-1.42.613.5-1.60.9-0.42.0-1.1-0.4-0.6-0.9-0.21.33.92.31.9-1.56.3-0.80.4-0.9
Percentage of InterestAndDividendIncomeOperating cbsh:OtherElimination0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2111651651674859135139137119137140140125115106112961041001019492931079092100969396101968994981059992971028886828762
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating100.278.877.075.222.727.059.860.157.552.659.062.662.460.857.154.858.051.457.755.856.355.154.355.163.259.158.561.957.458.659.362.457.556.555.460.660.558.753.457.257.450.348.845.947.133.1

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:StatementBusinessSegments

cbsh:CommercialSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value898185816755596156566463625862585753585956575952575455575756736253
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments42.249.451.948.4139.192.043.544.541.247.046.645.344.346.854.155.251.355.555.459.355.360.464.356.853.260.359.857.659.559.975.962.255.3
Percentage of InterestAndDividendIncomeOperating42.338.940.036.431.624.826.026.723.724.727.528.427.628.530.930.329.728.532.033.131.133.334.931.333.635.735.035.734.135.145.038.831.8
Percentage of InterestAndDividendIncomeOperating cbsh:CommercialSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:ConsumerSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value383541373724303125212425232023221917202220181920201720222017202117
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments18.021.625.222.376.541.222.222.618.517.917.718.116.416.720.420.917.218.319.522.420.619.821.721.619.118.922.022.121.418.321.720.818.2
Percentage of InterestAndDividendIncomeOperating18.017.119.416.717.411.113.313.610.79.410.411.310.210.211.611.510.09.411.212.511.610.911.811.912.111.212.913.712.310.712.913.010.5
Percentage of InterestAndDividendIncomeOperating cbsh:ConsumerSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:OtherElimination


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value48124.08517-83.693-48.38517182816232630246.5013.816136.0626.474-1.0095.0852.204-4.5822.814111.735-0.6590.9650.2745.668-11.5211.8559.521
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments22.77.62.510.2-172.9-80.913.213.421.014.117.418.822.019.25.63.612.56.36.2-1.05.02.3-5.03.010.61.9-0.71.00.36.0-12.01.89.9
Percentage of InterestAndDividendIncomeOperating22.76.01.97.7-39.2-21.87.98.012.17.410.311.713.711.73.22.07.23.23.6-0.62.81.3-2.71.76.71.1-0.40.60.23.5-7.11.15.7
Percentage of InterestAndDividendIncomeOperating cbsh:OtherElimination0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:SegmentTotals


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value163152161150132108117120108102113114109101108102989098101969296909688939995881079986
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments77.392.497.589.8272.9180.986.886.679.085.982.681.278.080.894.496.487.593.793.8101.095.097.7105.097.089.498.1100.799.099.794.4112.098.290.1
Percentage of InterestAndDividendIncomeOperating77.472.975.167.561.948.851.952.045.545.248.750.948.749.253.952.950.748.254.156.453.553.856.953.456.558.058.961.357.355.366.461.351.8
Percentage of InterestAndDividendIncomeOperating cbsh:SegmentTotals0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:WealthSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value363533322728282726252525242122212119191919161717181717191815131515
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments17.121.420.419.157.347.721.119.619.221.018.317.917.417.319.820.319.019.818.919.219.017.519.018.617.118.918.919.318.816.114.415.116.6
Percentage of InterestAndDividendIncomeOperating17.116.915.714.313.012.912.611.711.111.010.811.210.910.511.311.111.010.210.910.710.79.710.310.210.811.211.012.010.89.48.59.49.5
Percentage of InterestAndDividendIncomeOperating cbsh:WealthSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value453233349.6611028292822262629232032332432303129272732282931302930323028273234322931322724262718
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating21.415.315.415.44.54.612.412.612.110.011.411.913.111.310.016.617.113.217.817.317.517.116.316.519.018.618.319.218.118.518.720.218.018.216.219.719.719.417.018.618.415.613.814.514.89.8

Income Taxes Paid Net

us-gaap:IncomeTaxesPaidNet

us-gaap:IncomeTaxesPaidNet


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value522.5131533.6631.172228241.353821240.1473332512.853128572.6582428392.953344045-0.8073018632.0311439559.2712922540.455253638-0.169
Percentage of IncomeTaxesPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating25.11.214.624.21.70.59.712.110.40.616.39.411.00.116.516.926.71.517.116.031.81.514.417.022.91.921.525.227.4-0.518.511.637.91.38.824.131.85.517.213.030.40.314.420.720.7-0.1

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.1513.9494.9637.152102024282624201614131111109.7248.2968.1188.2368.3537.2557.0776.926.8446.9877.0957.0746.9327.2767.4387.7978.4028.9329.3839.519101112131416192125
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating1.51.92.33.24.89.210.612.211.210.78.97.66.56.45.76.05.65.24.64.54.64.94.34.24.14.54.44.44.24.34.54.64.75.35.25.75.56.06.67.17.58.49.410.911.913.5

Interest Income Expense Net

us-gaap:InterestIncomeExpenseNet

us-gaap:InterestIncomeExpenseNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value207205209215203201202203211203212207210192190182182178173171171163162162163146151154160153154154159150161153165159161158164160160159163162
Percentage of InterestIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating98.598.197.796.895.290.889.487.888.889.391.192.493.593.694.394.094.494.895.495.595.495.195.795.895.995.595.695.695.895.795.595.495.394.794.894.394.594.093.492.992.591.690.689.188.186.5

us-gaap:InterestIncomeExpenseNet us-gaap:StatementBusinessSegments

cbsh:CommercialSegment


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value11411011411110285868485858987858284828179807877757874737072727171827067
Percentage of InterestIncomeExpenseNet55.153.554.551.850.642.642.941.740.242.242.242.340.642.644.644.944.744.846.345.944.946.448.145.745.048.447.846.644.646.453.145.542.5
Percentage of InterestAndDividendIncomeOperating54.352.553.350.148.238.738.436.635.737.738.439.138.039.942.142.242.242.444.243.842.844.146.043.843.246.245.744.542.744.450.743.440.5
Percentage of InterestAndDividendIncomeOperating cbsh:CommercialSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:ConsumerSegment


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value807779808178798079767674737171706967676767666767666567676765676766
Percentage of InterestIncomeExpenseNet38.937.938.137.540.039.339.339.437.437.836.036.134.837.037.738.837.937.839.039.339.140.641.341.440.644.944.543.842.242.843.343.442.0
Percentage of InterestAndDividendIncomeOperating38.337.237.236.338.135.735.134.633.233.732.833.332.634.735.536.435.835.837.237.637.338.739.539.739.042.942.641.940.441.041.341.440.0
Percentage of InterestAndDividendIncomeOperating cbsh:ConsumerSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:OtherElimination


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value-5.1210.183-0.7387.9015.57723232634293433392721181919141416106.6121012-1.0651.2155.035116.541-4.4917.20214
Percentage of InterestIncomeExpenseNet-2.50.1-0.43.72.711.611.813.316.414.316.216.018.914.511.59.910.910.88.18.59.66.44.16.57.8-0.70.83.37.04.3-2.94.79.3
Percentage of InterestAndDividendIncomeOperating-2.40.1-0.33.52.610.610.511.614.612.814.814.817.713.610.89.310.310.37.88.19.26.13.96.27.5-0.70.83.16.74.1-2.84.48.9
Percentage of InterestAndDividendIncomeOperating cbsh:OtherElimination0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:SegmentTotals


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value213205210208197177178176176174177174171164168164162158159156155153155151150147150149149146159147144
Percentage of InterestIncomeExpenseNet102.599.9100.496.397.388.488.286.783.685.783.884.081.185.588.590.189.189.291.991.590.493.695.993.592.2100.799.296.793.095.7102.995.390.7
Percentage of InterestAndDividendIncomeOperating100.998.098.093.392.680.278.976.274.276.576.477.775.880.183.484.784.284.687.787.486.289.191.889.688.596.294.892.589.191.698.391.086.5
Percentage of InterestAndDividendIncomeOperating cbsh:SegmentTotals0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:WealthSegment


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1717161513121211121111111111111111111110101010101010109.805109.911109.9719.938
Percentage of InterestIncomeExpenseNet8.58.57.77.16.66.46.05.75.95.75.65.65.65.96.26.46.56.66.66.36.46.66.66.46.67.46.86.36.26.56.56.46.2
Percentage of InterestAndDividendIncomeOperating8.48.37.66.96.35.95.45.05.35.15.15.25.35.65.86.06.26.36.36.06.16.36.36.16.37.16.56.16.06.26.26.15.9
Percentage of InterestAndDividendIncomeOperating cbsh:WealthSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Interest Paid Net

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.1565.7536.7379.676132224262521191514131111119.6857.4587.9068.4598.0736.8236.9737.1476.8176.947.3367.0736.8697.4768.5198.2818.1569.137109.818101113161419222327
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating2.02.73.14.36.210.210.711.510.59.58.27.06.46.75.65.85.95.24.14.44.74.74.04.14.24.54.44.54.24.34.65.35.05.15.46.35.66.06.78.19.18.411.012.512.814.6

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1621301291323951106109107971091121101009474787171686965636474616268666465686561666670656165696061555944
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.735.538.338.834.434.931.232.323.5

us-gaap:NetIncomeLoss cbsh:IncomePerCommonShare

cbsh:BasicIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value162130129132395110610910797109112110100947478717168696563647461626866646568656166667065
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.7
Percentage of InterestAndDividendIncomeOperating cbsh:BasicIncomePerCommonShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss Attributable To Noncontrolling Interest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3923000.02257000.02307000.0907000.0-1132000.0-2254000.0398000.0838000.0328000.0-83000.01108000.01493000.0994000.01077000.0628000.0-338000.029000.0198000.0795000.0605000.0-85000.0148000.0715000.0601000.0970000.0959000.01017000.0836000.0-631000.0-192000.0-90000.0221000.0234000.0-209000.0-188000.0780000.0503000.01015000.01543000.0657000.0583000.0497000.0304000.0136000.084000.0-359000.0
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating1.91.11.10.4-0.5-1.00.20.40.1-0.00.50.70.40.50.3-0.20.00.10.40.3-0.00.10.40.40.60.60.60.5-0.4-0.1-0.10.10.1-0.1-0.10.50.30.60.90.40.30.30.20.10.0-0.2

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1621301291243749104106105941071101089892727669696667636162725860666664656865
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.556.017.622.446.246.244.341.646.149.147.947.945.737.239.636.838.237.037.636.736.236.942.338.438.141.039.740.240.742.139.3

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic cbsh:IncomePerCommonShare

cbsh:BasicIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1621301291243749104106105941071101089892727669696667636162725860666664656865
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.556.017.622.446.246.244.341.646.149.147.947.945.737.239.636.838.237.037.636.736.236.942.338.438.141.039.740.240.742.139.3
Percentage of InterestAndDividendIncomeOperating cbsh:BasicIncomePerCommonShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Diluted

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted cbsh:IncomePerCommonShare

us-gaap:NetIncomeLossAvailableToCommonStockholdersDiluted

cbsh:DilutedIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value1621301291243749104106105941071101089892727669696667636162725860666664656865
Percentage of NetIncomeLossAvailableToCommonStockholdersDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.556.017.622.446.246.244.341.646.149.147.947.945.737.239.636.838.237.037.636.736.236.942.338.438.141.039.740.240.742.139.3
Percentage of InterestAndDividendIncomeOperating cbsh:DilutedIncomePerCommonShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value51-162.625-12.058-5.82696142-33.72935967676-32.815-19.218-73.283-52.953241119-110.107-13.3423170-33.16616-42.928291.862-24.0834330-16.2944.161-107.899-6.581-29.69629187.518
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating24.5-77.6-5.6-2.645.164.4-14.915.240.733.633.0-14.6-8.5-35.6-26.312.96.010.3-60.7-7.417.540.9-19.510.0-25.219.41.2-14.926.119.2-10.02.6-64.5-4.1-17.418.010.74.4

us-gaap:OtherComprehensiveIncomeLossNetOfTax cbsh:ComponentsOfOtherComprehensiveIncome

cbsh:PensionLoss


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.4380.437-4.2160.3270.3550.3560.0010.3890.3880.389-0.5160.3930.3940.393-1.3310.3490.3410.340.1910.3590.3560.3621.3170.2830.4060.406-7.9020.2230.2230.2239.9630.4760.4750.475-7.2440.4530.4530.452
Percentage of OtherComprehensiveIncomeLossNetOfTax0.8-0.335.0-5.60.40.2-0.01.10.40.5-0.7-1.2-2.1-0.52.51.42.91.7-0.2-2.71.10.5-4.01.7-0.91.4-424.4-0.90.50.7-61.111.4-0.4-7.224.41.52.46.0
Percentage of InterestAndDividendIncomeOperating0.20.2-2.00.10.20.20.00.20.20.2-0.20.20.20.2-0.70.20.20.20.10.20.20.20.80.20.20.3-5.00.10.10.16.10.30.30.3-4.30.30.30.3
Percentage of InterestAndDividendIncomeOperating cbsh:PensionLoss0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:UnrealizedGainLossOnSecuritiesOther


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value55-158.676-3.7360.338678-20.29921767369-32.232-19.489-73.721-51.577241119-110.309-13.7473170-34.27116-43.4832910-24.0624330-26.3283.815-108.254-8.193-22.42625173.706
Percentage of OtherComprehensiveIncomeLossNetOfTax107.997.631.0-5.789.955.160.259.679.495.890.798.2101.4100.697.497.596.497.8100.2103.098.9100.1103.3100.3101.399.1539.299.999.698.7161.691.7100.3124.575.585.894.749.3
Percentage of InterestAndDividendIncomeOperating26.4-75.7-1.70.140.535.5-9.09.132.332.230.0-14.3-8.6-35.8-25.612.55.810.1-60.8-7.717.341.0-20.210.0-25.519.26.3-14.926.019.0-16.22.4-64.7-5.2-13.215.410.12.2
Percentage of InterestAndDividendIncomeOperating cbsh:UnrealizedGainLossOnSecuritiesOther0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-4.525-4.386-4.106-6.4839.30863-13.23114192.7797.884-1.0290.00.00.0
Percentage of OtherComprehensiveIncomeLossNetOfTax-8.82.734.1111.39.744.639.240.020.43.610.23.1-0.0-0.0-0.0
Percentage of InterestAndDividendIncomeOperating-2.1-2.1-1.9-2.94.428.7-5.86.18.31.23.4-0.50.00.00.0
Percentage of InterestAndDividendIncomeOperating us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value51-162.625-12.058-5.82696142-33.72935967676-32.815-19.218-73.283-52.953241119-110.107-13.3423170-33.16616-42.928291.862-24.0834330-16.2944.161-107.899-6.581-29.69629187.518
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating24.5-77.6-5.6-2.645.164.4-14.915.240.733.633.0-14.6-8.5-35.6-26.312.96.010.3-60.7-7.417.540.9-19.510.0-25.219.41.2-14.926.119.2-10.02.6-64.5-4.1-17.418.010.74.4
Percentage of InterestAndDividendIncomeOperating us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Preferred Stock Dividends Income Statement Impact

us-gaap:PreferredStockDividendsIncomeStatementImpact

us-gaap:PreferredStockDividendsIncomeStatementImpact


Preferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value0.07.4662.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.251.80.00.00.00.00.0
Percentage of PreferredStockDividendsIncomeStatementImpact0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.0
Percentage of InterestAndDividendIncomeOperating0.03.31.11.01.01.00.91.01.01.01.01.11.11.21.21.21.21.31.21.31.31.31.31.51.41.10.00.00.00.00.0

us-gaap:PreferredStockDividendsIncomeStatementImpact cbsh:IncomePerCommonShare

cbsh:BasicIncomePerCommonShare


Preferred
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value0.07.4662.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.252.251.80.00.00.00.00.0
Percentage of PreferredStockDividendsIncomeStatementImpact0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.0
Percentage of InterestAndDividendIncomeOperating0.03.31.11.01.01.00.91.01.01.01.01.11.11.21.21.21.21.31.21.31.31.31.31.51.41.10.00.00.00.00.0
Percentage of InterestAndDividendIncomeOperating cbsh:BasicIncomePerCommonShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1661331321333849107110108971101141111029474787172696965646575626369656465686660666671666366696062565943
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating78.763.561.659.818.222.447.347.545.442.647.650.849.349.547.138.240.838.139.938.638.838.138.038.644.240.540.142.739.340.140.642.239.538.339.140.940.839.336.438.639.134.735.131.332.323.3

us-gaap:ProfitLoss us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.9232.2572.3070.907-1.132-2.2540.3980.8380.328-0.0831.1081.4930.9941.0770.628-0.3380.0290.1980.7950.605-0.0850.1480.7150.6010.970.9591.0170.836-0.631-0.192-0.090.2210.234-0.209-0.1880.780.5031.0151.5430.6570.5830.4970.3040.1360.084-0.359
Percentage of ProfitLoss2.41.71.70.7-2.9-4.50.40.80.3-0.11.01.30.91.10.7-0.50.00.31.10.9-0.10.21.10.91.31.51.61.2-1.0-0.3-0.10.30.4-0.3-0.31.20.71.52.41.00.80.80.50.20.1-0.8
Percentage of InterestAndDividendIncomeOperating1.91.11.10.4-0.5-1.00.20.40.1-0.00.50.70.40.50.3-0.20.00.10.40.3-0.00.10.40.40.60.60.60.5-0.4-0.1-0.10.10.1-0.1-0.10.50.30.60.90.40.30.30.20.10.0-0.2
Percentage of InterestAndDividendIncomeOperating us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1621301291323951106109107971091121101009474787171686965636474616268666465686561666670656165696061555944
Percentage of ProfitLoss97.698.398.399.3102.9104.599.699.299.7100.199.098.799.198.999.3100.5100.099.798.999.1100.199.898.999.198.798.598.498.8101.0100.3100.199.799.6100.3100.398.899.398.597.699.099.299.299.599.899.9100.8
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.735.538.338.834.434.931.232.323.5
Percentage of InterestAndDividendIncomeOperating us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3385633269329223145330496267932606525876257722503325463250622452424611248332497925078253082564124734247092450624604239672370524049239942270123005228372307222452219102222722159208782074220526206492063819570190171850218120
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities

srt:ParentCompany


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-31
Value3444317429702759
Percentage of Assets10.512.211.711.1
Percentage of Assets10.512.211.711.1
Percentage of Assets srt:ParentCompany100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities

us-gaap:Liabilities


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3036229952295232814727137235402292722770226002199022526222542175321905221152227422450227442314022173221822205922237215962139021644216602041220743205632085720270198032004819988185711851218327184791850817439169461647816234
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets89.790.089.789.589.087.988.088.087.787.888.588.888.789.089.189.289.589.990.289.689.890.090.490.190.290.090.389.990.290.090.490.390.490.290.289.089.289.389.589.789.189.189.189.6

us-gaap:Liabilities us-gaap:ConsolidatedEntities

srt:ParentCompany


Liabilitiesus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-31
Value47403943
Percentage of Liabilities0.20.20.20.2
Percentage of Assets0.10.20.20.2
Percentage of Assets srt:ParentCompany1.41.31.31.6

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3385633269329223145330496267932606525876257722503325463250622452424611248332497925078253082564124734247092450624604239672370524049239942270123005228372307222452219102222722159208782074220526206492063819570190171850218120
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:ConsolidatedEntities

srt:ParentCompany


Liabilities
Period End2020-12-312019-12-312018-12-312017-12-31
Value3444317429702759
Percentage of LiabilitiesAndStockholdersEquity10.512.211.711.1
Percentage of Assets10.512.211.711.1
Percentage of Assets srt:ParentCompany100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value34853312339733053357325131343102316830372931280327672703271627002623255824952555252124422361236523092400233022852259227022102177210221752167230222262195216621272129206820211884
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.310.010.310.511.012.112.012.012.312.111.511.211.311.010.910.810.510.19.710.310.210.09.69.99.710.09.710.19.89.99.69.79.69.89.811.010.710.710.510.310.910.910.910.4

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities

srt:ParentCompany


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-31
Value3397313429312716
Percentage of StockholdersEquity100.0100.0100.0100.0
Percentage of Assets10.312.011.510.9
Percentage of Assets srt:ParentCompany98.698.798.798.4

Tier One Risk Based Capital

us-gaap:TierOneRiskBasedCapital dei:LegalEntity

us-gaap:TierOneRiskBasedCapital

cbsh:CommerceBank


Tier
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value26062421249422682111198318691809171316781604
Percentage of TierOneRiskBasedCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.99.39.89.18.28.17.87.87.78.18.7
Percentage of Assets cbsh:CommerceBank0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TierOneRiskBasedCapital us-gaap:ConsolidatedEntities

us-gaap:ConsolidatedEntities


Tier
Period End2020-12-312019-12-312018-12-312017-12-31
Value2950289028612567
Percentage of TierOneRiskBasedCapital113.2119.3114.7113.2
Percentage of Assets9.011.111.210.3
Percentage of Assets us-gaap:ConsolidatedEntities0.00.00.00.0

Cash

us-gaap:Cash us-gaap:ConsolidatedEntities

us-gaap:Cash

srt:ParentCompany


Cashus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-31
Value171301207151
Percentage of Cash100.0100.0100.0100.0
Percentage of Assets0.51.20.80.6
Percentage of Assets srt:ParentCompany5.09.57.05.5

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidatedEntities

us-gaap:CashAndCashEquivalentsAtCarryingValue

srt:ParentCompany


Cash
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value1713012071510.0510.053
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0
Percentage of Assets0.51.20.80.60.00.0
Percentage of Assets srt:ParentCompany5.09.57.05.50.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value254623802208155718188999078849616061209805547584524599545554801502
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.57.26.75.06.03.43.53.43.72.44.73.22.22.42.12.42.22.23.12.0

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value944923863852886897885863860841843
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.93.53.43.43.53.63.73.73.94.14.6

us-gaap:PropertyPlantAndEquipmentGross us-gaap:PropertyPlantAndEquipmentByType

cbsh:Rightofuseleasedassets


Property
Period End2020-12-312019-12-312018-12-31
Value29280.0
Percentage of PropertyPlantAndEquipmentGross3.13.10.0
Percentage of Assets0.10.10.0
Percentage of Assets cbsh:Rightofuseleasedassets0.00.00.0

us-gaap:BuildingAndBuildingImprovements


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value582566545540530541535529523517
Percentage of PropertyPlantAndEquipmentGross61.661.363.263.459.860.460.461.460.961.5
Percentage of Assets1.82.22.12.22.12.22.22.32.42.5
Percentage of Assets us-gaap:BuildingAndBuildingImprovements0.00.00.00.00.00.00.00.00.00.0

us-gaap:Equipment


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value239237226216258250244227229223
Percentage of PropertyPlantAndEquipmentGross25.325.726.225.529.127.927.626.326.726.6
Percentage of Assets0.70.90.90.91.01.01.01.01.01.1
Percentage of Assets us-gaap:Equipment0.00.00.00.00.00.00.00.00.00.0

us-gaap:Land


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value9391919498105106106107100
Percentage of PropertyPlantAndEquipmentGross9.99.910.611.111.111.712.012.312.512.0
Percentage of Assets0.30.40.40.40.40.40.40.50.50.5
Percentage of Assets us-gaap:Land0.00.00.00.00.00.00.00.00.00.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value573552530516549544528513502481459
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.72.12.12.12.12.22.22.22.32.32.5

Amortization Of Intangible Assets

us-gaap:AmortizationOfIntangibleAssets

us-gaap:AmortizationOfIntangibleAssets


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value745000.0951000.0800000.0859000.0442000.0268000.0400000.0395000.0373000.0342000.0348000.0318000.0313000.0321000.0300000.0338000.0330000.0348000.0300000.0374000.0399000.0395000.0400000.0445000.0472000.0473000.0500000.0499000.0549000.0559000.0600000.0463000.0532000.0557000.0600000.0594000.0669000.0684000.0
Percentage of AmortizationOfIntangibleAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AmortizationOfIntangibleAssets us-gaap:FiniteLivedIntangibleAssetsByMajorClass

cbsh:MortgageServicingRights


Amortization
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value-653000.0-857000.0-757000.0-331000.0-148000.0-307000.0-266000.0-236000.0-196000.0-168000.0-160000.0-145000.0-144000.0144000.0125000.092000.0101000.091000.092000.073000.060000.070000.074000.059000.050000.039000.037000.037000.038000.054000.0
Percentage of AmortizationOfIntangibleAssets-87.7-90.1-88.1-74.9-55.2-76.8-67.3-63.3-57.3-48.3-50.3-46.3-44.948.037.027.929.030.324.618.315.217.516.612.510.67.87.46.76.89.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cbsh:MortgageServicingRights0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CoreDeposits


Amortization
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value-92000.0-94000.0-94000.0-102000.0-111000.0-120000.0-119000.0-129000.0-137000.0-146000.0-146000.0-158000.0-168000.0-177000.0178000.0213000.0238000.0247000.0247000.0282000.0326000.0335000.0334000.0371000.0413000.0423000.0422000.0462000.0512000.0521000.0583000.0393000.0452000.0461000.0
Percentage of AmortizationOfIntangibleAssets-12.3-9.9-11.8-11.9-25.1-44.8-29.8-32.7-36.7-42.7-42.0-49.7-53.7-55.159.363.072.171.082.375.481.784.883.583.487.589.484.492.693.393.297.284.985.082.8
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CoreDeposits0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value371371371377368369370365363362333331331332335335334335337339342350352351353356357357346344349353352355357350350353360368374378383402
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.11.11.11.21.21.41.41.41.41.41.31.31.41.41.31.31.31.31.31.41.41.41.41.51.51.51.51.61.51.51.51.61.61.61.61.71.71.71.71.81.92.02.12.2

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value138138138138138138138138138138138138138138138138138138138138138138138138138138138138138138138138125125125125125125125125125125125125
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.40.40.40.50.50.50.50.50.60.50.60.60.60.60.60.60.50.50.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.60.70.70.7

us-gaap:Goodwill us-gaap:StatementBusinessSegments

cbsh:CommercialSegment


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value676767676767676767676767676767676767676767676767676767676767676757575757575757575757
Percentage of Goodwill48.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.648.545.445.445.445.445.445.445.445.445.445.4
Percentage of Assets0.20.20.20.20.20.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.3
Percentage of Assets cbsh:CommercialSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:ConsumerSegment


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value707070707070707070707070707070707070707070707070707070707070707067676767676767676767
Percentage of Goodwill50.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.950.951.054.054.054.054.054.054.054.054.054.054.0
Percentage of Assets0.20.20.20.20.20.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.4
Percentage of Assets cbsh:ConsumerSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Intangible Assets Net Excluding Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1413117.1837.1798.4339.5349.1398.7638.5118.7948.478.0837.8937.6187.3887.0026.76.7096.6216.5616.5396.6696.8266.9787.1437.457.7718.2498.8119.2689.054.5174.875.35.8046.3817.077.7148.4529.394101014
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.10.1

us-gaap:IntangibleAssetsNetExcludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass

cbsh:MortgageServicingRights


Intangible
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-31
Value5.7315.6256.7687.7497.2356.736.3416.4786.0085.4635.1054.6534.2453.6463.1062.8682.5332.1911.8431.6381.4611.2420.9940.8780.7770.7930.779
Percentage of IntangibleAssetsNetExcludingGoodwill79.878.480.381.379.276.874.573.770.967.664.761.157.552.146.442.738.333.428.224.621.417.813.911.810.09.68.4
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cbsh:MortgageServicingRights0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CoreDeposits


Intangible
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value1.4521.5541.6651.7851.9042.0332.172.3162.4622.622.7882.9653.1433.3563.5943.8414.0884.374.6965.0315.3655.7366.1496.5726.9947.4567.9688.4898.4223.9154.3674.8285.2895.8076.3846.977.5568.1999.612
Percentage of IntangibleAssetsNetExcludingGoodwill20.221.619.718.720.823.225.526.329.132.435.338.942.547.953.657.361.766.671.875.478.682.286.188.290.090.490.491.693.186.789.791.191.191.090.390.489.487.387.9
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.1
Percentage of Assets us-gaap:CoreDeposits0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet

us-gaap:FiniteLivedIntangibleAssetsNet


Finite
Period End2021-06-302021-03-312020-12-312019-12-31
Value109.4987.6079.534
Percentage of FiniteLivedIntangibleAssetsNet100.0100.0100.0100.0
Percentage of Assets0.00.00.00.0

us-gaap:FiniteLivedIntangibleAssetsNet us-gaap:FiniteLivedIntangibleAssetsByMajorClass

cbsh:MortgageServicingRights


Finite
Period End2021-06-302021-03-312020-12-31
Value9.3768.2346.249
Percentage of FiniteLivedIntangibleAssetsNet88.986.782.1
Percentage of Assets0.00.00.0
Percentage of Assets cbsh:MortgageServicingRights0.00.00.0

us-gaap:CoreDeposits


Finite
Period End2021-06-302021-03-312020-12-312019-12-312011-12-312010-12-31
Value1.1721.2641.3581.7856.979.612
Percentage of FiniteLivedIntangibleAssetsNet11.113.317.918.70.00.0
Percentage of Assets0.00.00.00.00.00.1
Percentage of Assets us-gaap:CoreDeposits0.00.00.00.00.00.0

us-gaap:ServicingContracts


Finite
Period End2020-12-312019-12-312011-12-312010-12-31
Value6.2497.7490.7441.325
Percentage of FiniteLivedIntangibleAssetsNet82.181.30.00.0
Percentage of Assets0.00.00.00.0
Percentage of Assets us-gaap:ServicingContracts0.00.00.00.0

Intangible Assets Net Including Goodwill

us-gaap:IntangibleAssetsNetIncludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:IntangibleAssetsNetIncludingGoodwill

cbsh:MortgageServicingRights


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value9.3768.2346.2495.7315.6256.7687.7497.2356.736.3416.4786.0085.4635.1054.6534.2453.6463.1062.8682.5332.1911.8431.6381.4611.2420.9940.878
Percentage of IntangibleAssetsNetIncludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets cbsh:MortgageServicingRights0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CoreDeposits


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value1.1721.2641.3581.4521.5541.6651.7851.9042.0332.172.3162.4622.622.7882.9653.1433.3563.5943.8414.0884.374.6965.0315.3655.7366.1496.572
Percentage of IntangibleAssetsNetIncludingGoodwill12.515.421.725.327.624.623.026.330.234.235.841.048.054.663.774.092.0115.7133.9161.4199.5254.8307.1367.2461.8618.6748.5
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CoreDeposits0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2020-12-312019-12-31
Value2826
Percentage of OperatingLeaseRightOfUseAsset100.0100.0
Percentage of Assets0.10.1

Equity Securities Fv Ni

us-gaap:EquitySecuritiesFvNi

us-gaap:EquitySecuritiesFvNi


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value6.9812.9312.9662.8032.7112.6332.9292.9022.8472.8082.58548
Percentage of EquitySecuritiesFvNi100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.2

us-gaap:EquitySecuritiesFvNi us-gaap:ConsolidatedEntities

srt:ParentCompany


Equity
Period End2020-12-312019-12-312018-12-31
Value2.82.82.5
Percentage of EquitySecuritiesFvNi94.495.696.7
Percentage of Assets0.00.00.0
Percentage of Assets srt:ParentCompany0.10.10.1

us-gaap:EquitySecuritiesFvNi us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:FairValueInputsLevel1


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value6.9812.9312.9662.8032.7112.6332.9292.9022.8472.8082.58519
Percentage of EquitySecuritiesFvNi100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.040.7
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.1
Percentage of Assets us-gaap:FairValueInputsLevel10.00.00.00.00.00.00.00.00.00.00.00.0

Other Assets

us-gaap:OtherAssets

us-gaap:OtherAssets


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value508594567632699779476483639456382452437483401359387339608396436331534355321330380294306328316481529381353353355404405391376378385344
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.51.81.72.02.32.91.81.92.51.81.51.81.82.01.61.41.51.32.41.61.81.42.21.51.41.41.61.31.31.41.42.12.41.71.61.71.72.02.01.91.92.02.11.9

us-gaap:OtherAssets us-gaap:ConsolidatedEntities

srt:ParentCompany


Other
Period End2020-12-312019-12-312018-12-312017-12-31
Value26232319
Percentage of OtherAssets4.64.96.25.0
Percentage of Assets0.10.10.10.1
Percentage of Assets srt:ParentCompany0.80.70.80.7

Time Deposit Maturities Year One

us-gaap:TimeDepositMaturitiesYearOne

us-gaap:TimeDepositMaturitiesYearOne


Time
Period End2020-12-31
Value1627
Percentage of TimeDepositMaturitiesYearOne100.0
Percentage of Assets4.9

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value8210000.04795000.02925000.0601000.0302000.01449000.03788000.03414000.02632000.05458000.05851000.04717000.03396000.02606000.01624000.03933000.04324000.04862000.05349000.05392000.04905000.05254000.05428000.05738000.05439000.04793000.04053000.03038000.02378000.03132000.03755000.03953000.03960000.04046000.04447000.04636000.04218000.03870000.04314000.02751000.02199000.01768000.01477000.01677000.0
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-31
Value5305000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree


Lessee
Period End2020-12-31
Value4715000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour


Lessee
Period End2020-12-31
Value3454000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive


Lessee
Period End2020-12-31
Value2025000.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0
Percentage of Assets0.0

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive


Lessee
Period End2020-12-31
Value14
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets0.0

Operating Lease Liability

us-gaap:OperatingLeaseLiability

us-gaap:OperatingLeaseLiability


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-31
Value2927272727
Percentage of OperatingLeaseLiability100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.1

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-31
Value36
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0
Percentage of Assets0.1

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount


Lessee
Period End2020-12-31
Value6813000.0
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets0.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value34853312339733053357325131343102316830372931280327672703271627002623255824952555252124422361236523092400233022852259227022102177210221752167230222262195216621272129206820211884
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.310.010.310.511.012.112.012.012.312.111.511.211.311.010.910.810.510.19.710.310.210.09.69.99.710.09.710.19.89.99.69.79.69.89.811.010.710.710.510.310.910.910.910.4

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities

srt:ParentCompany


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-31
Value3397313429312716
Percentage of StockholdersEquity100.0100.0100.0100.0
Percentage of Assets10.312.011.510.9
Percentage of Assets srt:ParentCompany98.698.798.798.4

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value3493331733993306335832523138310631713043293728072771270527182704262825632501256025262447236723712315240523342288226222732214218121062179217123072230219921702129213120702023204619881927188515791530
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets10.310.010.310.511.012.112.012.012.312.211.511.211.311.010.910.810.510.19.810.410.210.09.69.99.810.09.710.19.810.09.69.79.69.89.811.010.810.710.510.310.910.910.90.00.00.010.40.00.0

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value22016833134334925311014410811-64.669-141.596-108.781-89.563146742301012113410232654891626084409.731262112913616613611811011583616395755846-56.72926
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest6.35.19.710.410.47.83.54.63.40.4-2.2-5.0-3.9-3.30.52.51.61.20.44.75.34.21.42.82.13.82.72.63.71.80.41.21.06.06.37.26.15.45.15.43.93.03.14.73.83.02.5-3.61.7
Percentage of Assets0.70.51.01.11.10.90.40.60.40.0-0.3-0.6-0.4-0.40.10.30.20.10.00.50.50.40.10.30.20.40.30.30.40.20.00.10.10.60.60.80.70.60.50.60.40.30.30.00.00.00.30.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value242424202436214021362133215120422077207420841804180418021815154815461544155213351333133213371283126112231229121512141273127911041094110111021033103310321042980979976971865862859854621475
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest69.473.071.764.763.665.668.665.865.568.271.064.365.166.666.857.358.860.262.152.152.854.456.554.154.550.852.753.153.756.057.850.652.050.550.844.846.347.048.046.045.947.148.042.343.444.645.339.331.1
Percentage of Assets7.27.37.46.87.08.08.37.98.18.38.27.27.47.37.36.26.26.16.15.45.45.45.45.45.35.15.15.45.35.65.54.95.05.05.05.05.05.05.04.75.05.15.20.00.00.04.70.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value589589589563563563563559559559559535535535535510510510510489489489489484484484484481481481481459458458458446446446446436436436433417417417415379359
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest16.917.817.317.116.817.318.018.017.618.419.019.119.319.819.718.919.419.920.419.119.420.020.720.420.920.120.721.021.321.221.721.121.821.021.119.320.020.320.620.520.521.121.420.421.021.722.024.023.5
Percentage of Assets1.71.81.81.81.82.12.22.22.22.22.22.12.22.22.22.02.02.02.02.02.02.02.02.02.02.02.02.12.12.12.12.02.12.12.12.12.22.22.22.12.22.32.30.00.00.02.30.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value8.214.7952.9250.6010.3021.4493.7883.4142.6325.4585.8514.7173.3962.6061.6243.9334.3244.8625.3495.3924.9055.2545.4285.7385.4394.7934.0533.0382.3783.1323.7553.9533.964.0464.4474.6364.2183.874.3142.7512.1991.7681.4771.1661.1671.1331.6772.8352.47
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest0.20.10.10.00.00.00.10.10.10.20.20.20.10.10.10.10.20.20.20.20.20.20.20.20.20.20.20.10.10.10.20.20.20.20.20.20.20.20.20.10.10.10.10.10.10.10.10.20.2
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value30417373326232224201463384307241493408325221440390337292515470424383555514463426583537492449610563517477717671620575690645596555669633593568633669
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest8.75.22.19.96.96.96.414.912.110.18.217.614.712.08.116.314.913.111.720.118.617.416.223.422.219.318.325.523.821.720.328.026.723.822.031.130.128.226.532.430.328.827.532.731.830.830.140.143.7
Percentage of Assets0.90.50.21.00.80.80.81.81.51.20.92.01.71.30.91.81.61.31.12.11.91.71.62.32.21.91.82.62.32.21.92.72.62.32.23.43.23.02.83.33.33.13.00.00.00.03.10.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value-53.018-39.08-32.97-69.05-69.112-69.149-37.548-251.663-106.106-60.547-34.236-33.174-15.854-15.681-14.473-9.895-10.373-7.588-15.294-50.538-51.707-52.653-26.116-168.493-143.565-6.868-16.562-199.63-203.174-17.193-10.097-23.528-35.771-32.501-7.58-60.644-61.388-22.872-8.362-96.205-14.515-0.733-2.371-2.323-2.153-2.052-0.838-0.761-2.477
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-1.5-1.2-1.0-2.1-2.1-2.1-1.2-8.1-3.3-2.0-1.2-1.2-0.6-0.6-0.5-0.4-0.4-0.3-0.6-2.0-2.0-2.2-1.1-7.1-6.2-0.3-0.7-8.7-9.0-0.8-0.5-1.1-1.7-1.5-0.3-2.6-2.8-1.0-0.4-4.5-0.7-0.0-0.1-0.1-0.1-0.1-0.0-0.0-0.2
Percentage of Assets-0.2-0.1-0.1-0.2-0.2-0.3-0.1-1.0-0.4-0.2-0.1-0.1-0.1-0.1-0.1-0.0-0.0-0.0-0.1-0.2-0.2-0.2-0.1-0.7-0.6-0.0-0.1-0.9-0.9-0.1-0.0-0.1-0.2-0.1-0.0-0.3-0.3-0.1-0.0-0.5-0.1-0.0-0.00.00.00.0-0.00.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value589589589563563563563559559559559535535535535510510510510489489489489484484484484481481481481459458458458446446446446436436436433415
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.71.81.81.81.82.12.22.22.22.22.22.12.22.22.22.02.02.02.02.02.02.02.02.02.02.02.02.12.12.12.12.02.12.12.12.12.22.22.22.12.22.32.32.3

Additional Paid In Capital

us-gaap:AdditionalPaidInCapital

us-gaap:AdditionalPaidInCapital


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value242424202436214021362133215120422077207420841804180418021815154815461544155213351333133213371283126112231229121512141273127911041094110111021033103310321042980979976971854
Percentage of AdditionalPaidInCapital100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.27.37.46.87.08.08.37.98.18.38.27.27.47.37.36.26.26.16.15.45.45.45.45.45.35.15.15.45.35.65.54.95.05.05.05.05.05.05.04.75.05.15.24.7

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value30417373326232224201463384307241493408325221440390337292515470424383555514463426583537492449610563517477717671620575690645596555568
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.90.50.21.00.80.80.81.81.51.20.92.01.71.30.91.81.61.31.12.11.91.71.62.32.21.91.82.62.32.21.92.72.62.32.23.43.23.02.83.33.33.13.03.1

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value22016833134334925311014410811-64.669-141.596-108.781-89.563146742301012113410232654891626084409.731262112913616613611811011583616346
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.70.51.01.11.10.90.40.60.40.0-0.3-0.6-0.4-0.40.10.30.20.10.00.50.50.40.10.30.20.40.30.30.40.20.00.10.10.60.60.80.70.60.50.60.40.30.30.3

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax cbsh:ComponentsOfOtherComprehensiveIncome

cbsh:PensionLoss


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value-24.243-24.681-25.118-20.902-21.229-21.584-21.94-21.941-22.33-22.718-23.107-22.591-22.984-23.378-19.629-18.298-18.647-18.988-19.328-19.519-19.878-20.234-20.596-21.913-22.196-22.602-23.008-15.106-15.329-15.552-15.775-25.738-26.214-26.689-27.164-19.92-20.373-20.826-21.278
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax-11.0-14.6-7.6-6.1-6.1-8.5-19.9-15.2-20.5-189.635.716.021.126.1-139.1-27.3-44.3-62.4-176.1-16.1-14.8-19.7-63.4-33.4-45.5-24.6-37.1-25.1-18.2-38.4-162.1-98.9-119.9-20.6-19.9-12.0-14.9-17.6-19.2
Percentage of Assets-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1
Percentage of Assets cbsh:PensionLoss0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

cbsh:UnrealizedGainLossOnSecuritiesOther


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value160105263267267180981199821-52.278-122.089-89.857-70.368308157462713715112049846711081719551214743152160182157139136
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax73.062.379.677.976.571.489.582.690.1176.680.886.282.678.6215.0122.1136.8152.3249.0113.7112.6116.8153.2128.0137.6120.6130.9118.3113.1127.6218.9183.0200.4117.2117.5110.0115.2118.5123.2
Percentage of Assets0.50.30.80.90.90.70.40.50.40.1-0.2-0.5-0.4-0.30.10.30.20.20.10.60.60.50.20.40.30.50.30.30.40.20.10.20.20.70.70.90.80.70.7
Percentage of Assets cbsh:UnrealizedGainLossOnSecuritiesOther0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value83889296103933043299.6346.855-1.0290.00.00.00.00.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax38.052.328.028.229.637.127.430.227.080.4-10.60.7-0.0-0.00.00.00.0
Percentage of Assets0.20.30.30.30.30.40.10.20.10.00.0-0.00.00.00.00.00.0
Percentage of Assets us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value533932696969372511066034331515149.895107.58815505152261681436.8681619920317102335327.586061228.36296140.7332.3710.838
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.20.10.10.20.20.30.11.00.40.20.10.10.10.10.10.00.00.00.10.20.20.20.10.70.60.00.10.90.90.10.00.10.20.10.00.30.30.10.00.50.10.00.00.0

Minority Interest

us-gaap:MinorityInterest

us-gaap:MinorityInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value8210000.04795000.02925000.0601000.0302000.01449000.03788000.03414000.02632000.05458000.05851000.04717000.03396000.02606000.01624000.03933000.04324000.04862000.05349000.05392000.04905000.05254000.05428000.05738000.05439000.04793000.04053000.03038000.02378000.03132000.03755000.03953000.03960000.04046000.04447000.04636000.04218000.03870000.04314000.02751000.02199000.01768000.01477000.01677000.0
Percentage of MinorityInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.793.9333.6843.7653.7393.7293.4893.4863.3993.483.2863.1613.1043.292.9562.9543.063.1352.6242.6142.8763.4112.4452.452.5122.742.1982.1632.2072.2611.8221.8571.5251.2231.2961.151.1481.4071.1171.2423.628-1.256-10.691.2835.226-1.84
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.793.9333.6843.7653.7393.7293.4893.4863.3993.483.2863.1613.1043.292.9562.9543.063.1352.6242.6142.8763.4112.4452.452.5122.742.1982.1632.2072.2611.8221.8571.5251.2231.2961.151.1481.4071.1171.2423.628-1.256-10.691.2835.226-1.84
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Minority Interest Decrease From Distributions To Noncontrolling Interest Holders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value508000.0387000.0-17000.0608000.015000.085000.024000.056000.03154000.0310000.0-26000.0172000.0204000.095000.0-12000.053000.0567000.0685000.0838000.0118000.0264000.0322000.01025000.0302000.0324000.0219000.02000.0176000.0123000.0431000.0108000.0228000.0320000.0192000.01000.0362000.0155000.01459000.0-20000.0105000.0564000.0-206000.0-737000.0137000.0420000.0-185000.0
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value508000.0387000.0-17000.0608000.015000.085000.024000.056000.03154000.0310000.0-26000.0172000.0204000.095000.0-12000.053000.0567000.0685000.0838000.0118000.0264000.0322000.01025000.0302000.0324000.0219000.02000.0176000.0123000.0431000.0108000.0228000.0320000.0192000.01000.0362000.0155000.01459000.0-20000.0105000.0564000.0-206000.0-737000.0137000.0420000.0-185000.0
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value125201151242149791351251091421051581441439812270141865594195108598957576871217212069988791831209611692101265311149-54.738
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating59.596.270.6108.870.336.059.854.246.062.445.570.663.969.949.163.036.575.247.530.852.8113.86.050.457.562.447.347.452.175.944.574.541.861.851.656.447.770.755.668.052.258.0149.5173.980.8-29.1

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-368.432-327.731-947.561-1503.448-2657.901-281.594-275.902-306.233-116.708-31.32235-379.699-30.457283-100.479176318-173.378-712.4-110.913-65.42383-570.752-430.801406-600.464-852.32327-319.658-218.6-528.21620731-424.37-974.05826-218.3955.363-1114.077-403.595-250.073-417.09-112.653-867.298-41.125366
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-174.5-156.3-441.3-673.8-1246.0-127.1-121.7-132.1-49.0-13.715.4-168.9-13.5137.6-49.890.7164.5-92.2-392.5-61.8-36.348.5-336.2-254.7238.4-392.5-536.3202.6-190.8-136.6-325.8128.018.8-267.3-572.416.1-125.13.2-643.1-236.2-140.4-237.2-63.5-484.8-22.2194.9

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value408298144610003426193163103362-713.667262478-150.986-366.757-86.368-229.805-396.601-211.762941-102.50539-225.919604102-355.581-43.4991155-247.09248-424.203776191-292.5261671096-59.53211-208.634965-30.088474424-112.893325189-422.322
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating193.4142.4673.8448.31606.387.472.344.7151.9-313.2112.7213.0-66.9-178.0-42.8-118.3-204.9-112.6518.7-57.221.9-131.3356.160.9-208.5-28.4727.0-152.729.2-265.1478.9117.9-174.9105.4644.5-36.5121.1-122.8557.5-17.6266.5241.2-63.6181.9102.6-224.6

Increase Decrease In Other Operating Capital Net

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value17-11.178140-151.8511860148.0293218204.994-10.746-9.21215-10.49610-8.1822.064146.4333.352103.207-12.4849.6427.2850.662-11.2296.5246.224-7.46-14.39280.0763.101-4.419125.483-13.92337-26.341374.143-61.96622
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value125201151242149791351251091421051581441439812270141865594195108598957576871217212069988791831209611692101265311149-54.738
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating59.596.270.6108.870.336.059.854.246.062.445.570.663.969.949.163.036.575.247.530.852.8113.86.050.457.562.447.347.452.175.944.574.541.861.851.656.447.770.755.668.052.258.0149.5173.980.8-29.1

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1621301291323951106109107971091121101009474787171686965636474616268666465686561666670656165696061555944
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.735.538.338.834.434.931.232.323.5

us-gaap:NetIncomeLoss cbsh:IncomePerCommonShare

cbsh:BasicIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value162130129132395110610910797109112110100947478717168696563647461626866646568656166667065
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.7
Percentage of InterestAndDividendIncomeOperating cbsh:BasicIncomePerCommonShare0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1661331321333849107110108971101141111029474787172696965646575626369656465686660666671666366696062565943
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating78.763.561.659.818.222.447.347.545.442.647.650.849.349.547.138.240.838.139.938.638.838.138.038.644.240.540.142.739.340.140.642.239.538.339.140.940.839.336.438.639.134.735.131.332.323.3

us-gaap:ProfitLoss us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.9232.2572.3070.907-1.132-2.2540.3980.8380.328-0.0831.1081.4930.9941.0770.628-0.3380.0290.1980.7950.605-0.0850.1480.7150.6010.970.9591.0170.836-0.631-0.192-0.090.2210.234-0.209-0.1880.780.5031.0151.5430.6570.5830.4970.3040.1360.084-0.359
Percentage of ProfitLoss2.41.71.70.7-2.9-4.50.40.80.3-0.11.01.30.91.10.7-0.50.00.31.10.9-0.10.21.10.91.31.51.61.2-1.0-0.3-0.10.30.4-0.3-0.31.20.71.52.41.00.80.80.50.20.1-0.8
Percentage of InterestAndDividendIncomeOperating1.91.11.10.4-0.5-1.00.20.40.1-0.00.50.70.40.50.3-0.20.00.10.40.3-0.00.10.40.40.60.60.60.5-0.4-0.1-0.10.10.1-0.1-0.10.50.30.60.90.40.30.30.20.10.0-0.2
Percentage of InterestAndDividendIncomeOperating us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1621301291323951106109107971091121101009474787171686965636474616268666465686561666670656165696061555944
Percentage of ProfitLoss97.698.398.399.3102.9104.599.699.299.7100.199.098.799.198.999.3100.5100.099.798.999.1100.199.898.999.198.798.598.498.8101.0100.3100.199.799.6100.3100.398.899.398.597.699.099.299.299.599.899.9100.8
Percentage of InterestAndDividendIncomeOperating76.962.560.559.418.723.447.247.145.342.647.150.148.949.046.838.440.838.039.438.238.838.037.538.243.639.939.542.139.740.240.742.139.338.439.240.440.538.735.538.338.834.434.931.232.323.5
Percentage of InterestAndDividendIncomeOperating us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.793.9333.6843.7653.7373.7293.4893.4863.3993.483.2863.1613.1043.292.9562.9543.063.1352.6242.6142.8763.4112.4452.452.5122.742.1982.1632.2072.2611.8221.8571.5251.2231.2961.151.1481.4071.1171.2421.1161.2561.3521.2831.5461.84
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-368.432-327.731-947.561-1503.448-2657.901-281.594-275.902-306.233-116.708-31.32235-379.699-30.457283-100.479176318-173.378-712.4-110.913-65.42383-570.752-430.801406-600.464-852.32327-319.658-218.6-528.21620731-424.37-974.05826-218.3955.363-1114.077-403.595-250.073-417.09-112.653-867.298-41.125366
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-174.5-156.3-441.3-673.8-1246.0-127.1-121.7-132.1-49.0-13.715.4-168.9-13.5137.6-49.890.7164.5-92.2-392.5-61.8-36.348.5-336.2-254.7238.4-392.5-536.3202.6-190.8-136.6-325.8128.018.8-267.3-572.416.1-125.13.2-643.1-236.2-140.4-237.2-63.5-484.8-22.2194.9

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11103.942156.1037.574139.1529.00611117.8338.5434.9827.9718.7368.6615.4565.9994.836.267.3899.1797.1956.9488.5759.45319103.9545.118.0184.8465.867157.546.315.3935.1975.0025.3145.8195.3673.7666.6132.782
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments To Acquire Investments

us-gaap:PaymentsToAcquireInvestments

us-gaap:PaymentsToAcquireInvestments


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1512119418562487207856955633453943257077145029878144614348290866523318010347965851125118311756862888821337593411465589185581591111610088019471229735305
Percentage of PaymentsToAcquireInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value408298144610003426193163103362-713.667262478-150.986-366.757-86.368-229.805-396.601-211.762941-102.50539-225.919604102-355.581-43.4991155-247.09248-424.203776191-292.5261671096-59.53211-208.634965-30.088474424-112.893325189-422.322
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating193.4142.4673.8448.31606.387.472.344.7151.9-313.2112.7213.0-66.9-178.0-42.8-118.3-204.9-112.6518.7-57.221.9-131.3356.160.9-208.5-28.4727.0-152.729.2-265.1478.9117.9-174.9105.4644.5-36.5121.1-122.8557.5-17.6266.5241.2-63.6181.9102.6-224.6

Payments Of Dividends Common Stock

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsOfDividendsCommonStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3030303030302727282824252525222222222121212120202121202021212020202015020391.0741919202019191919
Percentage of PaymentsOfDividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value13250.4030.1670.448531433463935202.002176.4510.6923.3447.2840.9051.0141.033614-74.428811.7181.9340.051188200.158231529293.88440310.04382144.311390.1040.0650.878
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod


Share
Period End2021-06-302021-03-312020-12-31
Value072416.05052.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod0.0100.0100.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value131763.585140.13615150115191167131
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value95667773118114124120129137127
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value1300000.01400000.01257000.01208000.01228000.01278000.01312000.01428000.01581000.01584000.01613000.02714000.0
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss

cbsh:AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss


A
Period End2021-06-302021-03-312020-12-31
Value-64.799-8.2
Percentage of AFSsecuritiesinlosspositionatperiodendchangeinunrealizedloss100.0100.0100.0

cbsh:AccruedInterestReceivableOnHeldForInvestmentLoansWriteOff us-gaap:FinancingReceivablePortfolioSegment

cbsh:AccruedInterestReceivableOnHeldForInvestmentLoansWriteOff

cbsh:PersonalBankingPortfolioSegment


Accrued
Period End2020-12-312020-09-302020-06-302020-03-31
Value1300000.01700000.0751000.01900000.0
Percentage of AccruedInterestReceivableOnHeldForInvestmentLoansWriteOff100.0100.0100.0100.0

us-gaap:CommercialPortfolioSegment


Accrued
Period End2020-12-312020-09-302020-06-302020-03-31
Value71000.089000.0115000.054000.0
Percentage of AccruedInterestReceivableOnHeldForInvestmentLoansWriteOff5.55.215.32.8

cbsh:BankCardTransactionFees

cbsh:BankCardTransactionFees


Bank
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value423739373340414442394442434142393735
Percentage of BankCardTransactionFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:CapitalizedInterestOrDividends

cbsh:CapitalizedInterestOrDividends


Capitalized
Period End2021-06-302020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value23000.00029000.01000.0031000.00-1000.00035000.01000.00033000.015000.015000.014000.048000.024000.0052000.065000.032000.045000.013000.054000.0145000.063000.062000.061000.0215000.0118000.015000.0177000.0232000.001000.079000.02000.06000.0-42000.0
Percentage of CapitalizedInterestOrDividends100.00.00.0100.0100.00.0100.00.0100.00.00.0100.0100.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

cbsh:CapitalizedInterestOrDividends us-gaap:FairValueByAssetClass

us-gaap:PrivateEquityFunds


Capitalized
Period End2021-06-302020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value23000.00029000.01000.0031000.00-1000.00035000.01000.00033000.015000.015000.014000.048000.024000.0052000.065000.032000.045000.013000.054000.0145000.063000.062000.061000.0215000.0118000.015000.0177000.0232000.001000.0
Percentage of CapitalizedInterestOrDividends100.00.00.0100.0100.00.0100.00.0100.00.00.0100.0100.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0

cbsh:ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements

cbsh:ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value18108.3625.459-4.682-13.063-0.1882.88-0.214-0.9911.2894.9474.5385.052.035-4.4340.92-1.9650.069-1.995-2.043-0.178-1.947-0.8271.2953.6813.8953.204-4.76916-4.6270.9160.367-1.719-3.852.7370.6074.1230.8393.1582.7131.5441.4381.6440.07
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements us-gaap:FairValueByAssetClass

cbsh:DerivativeLevelThreeUnobservableInputs


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value1.4342.050.3493.052.815-0.055-0.4590.860.9620.851-0.1890.6720.7470.745-0.160.7640.8720.913-0.5620.9260.7670.736-0.120.3940.420.381-0.055-0.0210.0890.1050.0580.0510.0690.0560.019-0.0370.007-0.002-0.2190.2370.108
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements7.919.74.255.9-60.10.4244.129.9-449.5-85.9-14.713.616.514.8-7.9-17.294.8-46.5-814.5-46.4-37.5-413.56.2-47.632.410.4-1.4-0.7-1.90.6-1.35.618.8-3.3-0.5-1.41.2-0.0-26.17.54.0

us-gaap:PrivateEquityFunds


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value168.3658.0132.409-7.497-13.0080.2712.02-1.176-1.8421.4784.2753.7914.3052.195-5.1980.048-2.8780.631-2.921-2.81-0.914-1.827-1.2210.8753.33.953.225-4.85816-4.6850.8650.298-1.775-3.8692.7740.64.1251.0582.9212.605
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements92.180.395.844.1160.199.6-144.170.1549.5185.9114.786.483.585.2107.9117.25.2146.5914.5146.4137.5513.593.8147.667.689.6101.4100.7101.999.4101.394.481.2103.3100.5101.498.8100.0126.192.596.0

cbsh:ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements us-gaap:IncomeStatementLocation

cbsh:InvestmentSecuritiesGainsLosses


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value168.3658.0132.409-7.497-13.0080.2712.02-1.176-1.8421.4784.2753.7914.3052.195-5.1980.048-2.8780.631-2.921-2.81-0.914-1.827-1.2210.8753.33.953.225-4.85816-4.6850.8650.298-1.775-3.8692.7740.64.125
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements92.180.395.844.1160.199.6-144.170.1549.5185.9114.786.483.585.2107.9117.25.2146.5914.5146.4137.5513.593.8147.667.689.6101.4100.7101.999.4101.394.481.2103.3100.5101.498.8100.0

cbsh:LoansFeesAndSales


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value1.821.8550.0893.1372.5470.0-0.3650.8230.9350.823-0.1440.6790.730.582-0.1760.7560.8710.903-0.5260.8760.790.771-0.1880.4510.3450.4080.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements10.117.81.157.5-54.4-0.0194.128.6-436.9-83.0-11.213.716.111.5-8.6-17.194.7-46.0-762.3-43.9-38.7-433.19.7-54.526.611.10.00.0-0.00.0-0.00.00.0-0.0-0.00.00.00.0

cbsh:OtherNonInterestIncome


Change
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.3860.1950.26-0.0870.268-0.055-0.0940.0370.0270.028-0.045-0.0070.0170.1630.0160.0080.0010.01-0.0360.05-0.023-0.0350.068-0.0570.075-0.027-0.055-0.0210.0890.1050.0580.0510.0690.0560.019-0.0370.007-0.002
Percentage of ChangeInUnrealizedGainsOrLossesRelatedToAssetsHeldLevel3FairValueMeasurements-2.11.93.1-1.6-5.70.450.01.3-12.6-2.8-3.5-0.10.43.20.8-0.20.1-0.5-52.2-2.51.119.7-3.56.95.8-0.7-1.4-0.7-1.90.6-1.35.618.8-3.3-0.5-1.41.2-0.0

cbsh:Depositfeerevenue

cbsh:Depositfeerevenue


Depositfeerevenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2322242322232424232323232322
Percentage of Depositfeerevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:EffectOnInterestIncomeResultingFromModificationToCreditCardLoans

cbsh:EffectOnInterestIncomeResultingFromModificationToCreditCardLoans


Effect
Period End2021-06-302021-03-312020-12-31
Value-133000.01000000.0-135000.0
Percentage of EffectOnInterestIncomeResultingFromModificationToCreditCardLoans100.0100.0100.0

cbsh:EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow

srt:Maximum, cbsh:MortgageLoanCommitments


Embedded
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-31
Value-0.11.200.98600.004-0.0050.024
Percentage of EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow100.0100.00.0100.00.0100.0100.0100.0

srt:Minimum, cbsh:MortgageLoanCommitments


Embedded
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-31
Value0.10.6-0.10.60-0.0070.0010.006
Percentage of EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow-100.050.00.060.90.0-175.0-20.025.0

srt:WeightedAverage, cbsh:MortgageLoanCommitments


Embedded
Period End2021-06-302021-03-312020-12-312020-09-30
Value01.000.891
Percentage of EmbeddedServicingValueMortgageLoanCommitmentsDiscountedCashFlow-0.083.30.090.4

cbsh:FairValueAdjustmentsOtherSecurities us-gaap:FinancialInstrument

cbsh:FairValueAdjustmentsOtherSecurities

us-gaap:OtherInvestments


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value168.3658.0132.389-7.497-13.0080.2712.02-1.176-1.8421.4784.2753.7914.305
Percentage of FairValueAdjustmentsOtherSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value168.48.02.4-7.5-13.02.0-1.2-1.8
Percentage of FairValueAdjustmentsOtherSecurities99.6100.499.8100.5100.099.999.0102.097.7

cbsh:FairValueEstimatedMarketRatePercent us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:FairValueEstimatedMarketRatePercent

srt:Maximum, us-gaap:AuctionRateSecurities


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-0.31.7-0.62.269-0.0340.065-0.001-0.002-0.0030.043
Percentage of FairValueEstimatedMarketRatePercent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:Minimum, us-gaap:AuctionRateSecurities


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-0.31.4-0.41.874-0.0310.05700.003-0.0030.034
Percentage of FairValueEstimatedMarketRatePercent100.082.466.782.691.287.7-0.0-150.0100.079.1

srt:WeightedAverage, us-gaap:AuctionRateSecurities


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.21.4-0.41.874-0.0320.058
Percentage of FairValueEstimatedMarketRatePercent66.782.466.782.694.189.2

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value3000.03000.03000.0105000.05000.04000.04000.036000.037000.07000.07000.07000.09000.09000.010000.09000.023000.010000.010000.012000.069000.013000.0535000.022000.021000.0-130000.02126000.0-40000.041000.039000.043000.041000.057000.066000.053000.0176000.0147000.060000.0101000.0112000.098000.0307000.0312000.0137000.0127000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion us-gaap:FairValueByAssetClass

us-gaap:USStatesAndPoliticalSubdivisions


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value3000.03000.03000.0105000.05000.04000.04000.036000.037000.07000.07000.07000.09000.09000.010000.09000.023000.010000.010000.012000.069000.013000.0535000.022000.021000.0-130000.02126000.0-40000.041000.039000.043000.041000.057000.066000.053000.0176000.0147000.060000.0101000.0112000.098000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetDiscountAccretion100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities


Fair
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value5.6567.8932.5220.1550.1140.8075.017.8292.060.745100.3644.8794.0832.1852.2594.8251.1712.8940.5755.2662.0899.371.4370.2162.5774.5754.03.00.00.32.01.655.6350.00.03.2756.5910.0753.060.1792.4753.4531.2
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities us-gaap:FairValueByAssetClass

us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value5.6567.8932.5220.1550.1140.8075.017.8292.060.745100.3644.8794.0832.1852.2594.8251.1712.8940.5755.2662.0899.371.4370.2162.5774.5754.03.00.00.32.01.655.6350.00.03.2756.5910.0753.06
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchaseOfPrivateEquitySecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0

cbsh:FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple

srt:Maximum, us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value06.00006.00006.0
Percentage of FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple0.0100.00.00.00.0100.00.00.00.0100.0

srt:Minimum, us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value04.00004.00004.0
Percentage of FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple0.066.70.00.00.066.70.00.00.066.7

srt:WeightedAverage, us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value05.30.1005.3
Percentage of FairValueinputsEarningsbeforeinteresttaxesdepreciationamortizationEBITDAmultiple0.088.30.00.00.088.3

cbsh:GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal

cbsh:GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal


Gains
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value18000.0-1000.096000.0258000.01123000.0-1495000.0
Percentage of GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal100.0100.0100.0100.0100.0100.0

cbsh:GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal us-gaap:FairValueByAssetClass

us-gaap:USStatesAndPoliticalSubdivisions


Gains
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value18000.0-1000.096000.0258000.01123000.0-1495000.0
Percentage of GainsLossesIncludedInOCIAttributableToChangeInUnrealizedGainsLossesRelatingToAssetsStillHeldTotal100.0100.0100.0100.0100.0100.0

cbsh:ImpairmentAndImpairmentReversalsOfIntangibleAssetsFiniteLived us-gaap:FiniteLivedIntangibleAssetsByMajorClass

cbsh:ImpairmentAndImpairmentReversalsOfIntangibleAssetsFiniteLived

cbsh:MortgageServicingRights


Impairment
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value244000.01055000.0-28000.0795000.01056000.0-77000.095000.049000.0260000.0000-9000.0-7000.001000.0-7000.0-14000.05000.01000.01000.0-9000.0-6000.0-38000.0-15000.026000.0-12000.013000.0-14000.0-82000.0
Percentage of ImpairmentAndImpairmentReversalsOfIntangibleAssetsFiniteLived100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:IncomeAllocatedToUnvestedRestrictedStockholders cbsh:IncomePerCommonShare

cbsh:IncomeAllocatedToUnvestedRestrictedStockholders

cbsh:BasicIncomePerCommonShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value1478000.01200000.01219000.01173000.0353000.0470000.01023000.01040000.01012000.0944000.01137000.01161000.01139000.01121000.01098000.0862000.0943000.0945000.0951000.0913000.0940000.0894000.0871000.0884000.0997000.0796000.0795000.0879000.0856000.0802000.0787000.0808000.0750000.0594000.0709000.0626000.0666000.0562000.0
Percentage of IncomeAllocatedToUnvestedRestrictedStockholders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:DilutedIncomePerCommonShare


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value1475000.01198000.01218000.01170000.0354000.0469000.01021000.01039000.01009000.0943000.01134000.01159000.01136000.01118000.01095000.0860000.0941000.0942000.0949000.0912000.0938000.0893000.0869000.0883000.0995000.0794000.0793000.0877000.0854000.0799000.0785000.0806000.0747000.0593000.0713000.0623000.0665000.0561000.0
Percentage of IncomeAllocatedToUnvestedRestrictedStockholders99.899.899.999.7100.399.899.899.999.799.999.799.899.799.799.799.899.899.799.899.999.899.999.899.999.899.799.799.899.899.699.799.899.699.8100.699.599.899.8

cbsh:InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell

cbsh:InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value10111111107.4624.8323.6213.687
Percentage of InterestOnLongTermSecuritiesPurchasedUnderAgreementsToResell100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:InterestOnOtherBorrowings

cbsh:InterestOnOtherBorrowings


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1000.0-1000.0-18000.00701000.0331000.0489000.0453000.05000.05000.09000.012000.012000.012000.0381000.0906000.0911000.0888000.0902000.0906000.0907000.01253000.0907000.0898000.0890000.0879000.0878000.0880000.0875000.0851000.0868000.0855000.0829000.0812000.0848000.0851000.0-876000.0-906000.0-921000.0-925000.0-919000.0-915000.0-1721000.0-2729000.0-3791000.0-6705000.0
Percentage of InterestOnOtherBorrowings100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:InvestmentSecuritiesCalled

cbsh:InvestmentSecuritiesCalled


Investment
Period End2020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value4000000.0-2000000.009270000.0-1715000.0-2920000.02616000.001715000.000600000.00-2400000.01100000.00100000.0-84825000.000-2000000.0-38225000.0000-1250000.00-375000.0-525000.0-1925000.0-3000000.0-3000000.0-350000.0-4350000.0-1300000.0-1025000.0-5918000.0-5000000.0-1450000.0-1175000.0
Percentage of InvestmentSecuritiesCalled100.0100.00.0100.0100.0100.0100.00.0100.00.00.0100.00.0100.0100.00.0100.0100.00.00.0100.0100.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:InvestmentSecuritiesCalled us-gaap:FairValueByAssetClass

us-gaap:USStatesAndPoliticalSubdivisions


Investment
Period End2020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value0-2000000.009270000.0-1715000.0-2920000.02616000.001715000.000600000.00-2400000.01100000.00100000.0-84825000.000-2000000.0-38225000.0000-1250000.00-375000.0-525000.0-1925000.0-3000000.0-3000000.0-350000.0-4350000.0-1300000.0-1025000.0
Percentage of InvestmentSecuritiesCalled0.0100.00.0100.0100.0100.0100.00.0100.00.00.0100.00.0100.0100.00.0100.0100.00.00.0100.0100.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:LoanFeesAndSales

cbsh:LoanFeesAndSales


Loan
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value7.446109.0319.7694.6493.2353.4654.7554.2383.3093.0533.5793.2292.8623.0993.594.0913.1682.5833.1233.1962.512.1011.8552.1832.0891.3211.3671.2111.2091.5251.5531.3141.4731.4121.3581.7061.5611.6472.0342.0751.824115.833.4721.839
Percentage of LoanFeesAndSales100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:LoansNonrecurringBasisGainsLosses

cbsh:LoansNonrecurringBasisGainsLosses


Loans
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-2926000.0-4549000.0-135000.0-3063000.0-16000.0-124000.0-81000.0-228000.0170000.0-72000.0-79000.0-106000.0-12000.0-281000.0214000.0-210000.0-340000.0-74000.0-135000.0
Percentage of LoansNonrecurringBasisGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:MortgageServicingRightsNonrecurringBasisGainsLosses

cbsh:MortgageServicingRightsNonrecurringBasisGainsLosses


Mortgage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value244000.01055000.047000.028000.0-795000.0-1056000.077000.0-95000.0-49000.0-260000.00009000.07000.00-1000.07000.014000.0-5000.0
Percentage of MortgageServicingRightsNonrecurringBasisGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.00.0100.0100.0100.0100.0

cbsh:NetIncomeAvailableToCommonStockholdersExcludingIncomeAllocatedToUnvestedRestrictedStockholders cbsh:IncomePerCommonShare

cbsh:NetIncomeAvailableToCommonStockholdersExcludingIncomeAllocatedToUnvestedRestrictedStockholders

cbsh:BasicIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value16012912812337491031051049310610910697917175686865666260617158596565636567656066657065
Percentage of NetIncomeAvailableToCommonStockholdersExcludingIncomeAllocatedToUnvestedRestrictedStockholders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:DilutedIncomePerCommonShare


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value16012912812337491031051049310610910697917175686865666260617158596565636567656066657065
Percentage of NetIncomeAvailableToCommonStockholdersExcludingIncomeAllocatedToUnvestedRestrictedStockholders100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:NetIncreaseDecreaseInShortTermBorrowings

cbsh:NetIncreaseDecreaseInShortTermBorrowings


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-30
Value-1.5972.9893.252-0.693-754.986754-242.34252
Percentage of NetIncreaseDecreaseInShortTermBorrowings100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits

cbsh:NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value100585117713143642181315850-460.18-620.589237-150.146-82.20854-2.546-90.0522849502319-460.271421865-354.14-184.55218752-197.704-139.865-132.8581370293-724.917-138.4191222218420-84.876890384371334897107304-8.713
Percentage of NetIncreaseDecreaseNonInterestBearingSavingsInterestCheckingAndMoneyMarketDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:NonvestedShareAwardsForfeitedInPeriod

cbsh:NonvestedShareAwardsForfeitedInPeriod


Nonvested
Period End2021-06-302021-03-312020-12-31
Value8945.04037.04952.0
Percentage of NonvestedShareAwardsForfeitedInPeriod100.0100.0100.0

cbsh:NonvestedShareAwardsGrantedInPeriod

cbsh:NonvestedShareAwardsGrantedInPeriod


Nonvested
Period End2021-06-302021-03-312020-12-312013-12-312013-09-302013-03-31
Value5011.0197190.026211.024207.042674.070003.0
Percentage of NonvestedShareAwardsGrantedInPeriod100.0100.0100.0100.0100.0100.0

cbsh:NonvestedShareAwardsVestedInPeriod

cbsh:NonvestedShareAwardsVestedInPeriod


Nonvested
Period End2021-06-302021-03-312020-12-31
Value7885.0219700.017030.0
Percentage of NonvestedShareAwardsVestedInPeriod100.0100.0100.0

cbsh:OriginationOfLoansHeldForSale

cbsh:OriginationOfLoansHeldForSale


Origination
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312012-12-312012-09-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1531721431287.8163357796146546045445365623447444624272532170.00.00.00.00.00.0111244-15.789-661.00127516-227.463
Percentage of OriginationOfLoansHeldForSale100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:OtherSecuritiesGainOnSale us-gaap:FinancialInstrument

cbsh:OtherSecuritiesGainOnSale

us-gaap:OtherInvestments


Other
Period End2021-06-302021-03-312019-12-312019-09-302018-12-312018-09-30
Value88000.01523000.00000
Percentage of OtherSecuritiesGainOnSale100.0100.00.00.00.00.0

us-gaap:PrivateEquityFunds


Other
Period End2021-06-302021-03-312019-09-30
Value100000.01500000.00
Percentage of OtherSecuritiesGainOnSale113.698.50.0

cbsh:Paymentsforstockvalueissuedundersharebasedcompensationplans

cbsh:Paymentsforstockvalueissuedundersharebasedcompensationplans


Paymentsforstockvalueissuedundersharebasedcompensationplans
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value015000.0-16000.001000.026000.05000.00-1000.04000.001000.03000.06000.01000.001000.06000.0
Percentage of Paymentsforstockvalueissuedundersharebasedcompensationplans0.0100.0100.00.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0

cbsh:PercentofRevenuenotinscopeofASC606

cbsh:PercentofRevenuenotinscopeofASC606


Percentof
Period End2021-06-302021-03-312020-12-31
Value060.0-1.0
Percentage of PercentofRevenuenotinscopeofASC6060.0100.0100.0

cbsh:ProbabilityofFunding us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:ProbabilityofFunding

srt:Maximum, cbsh:MortgageLoanCommitments


Probabilityof
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-31
Value0100.0-1.098.8030.0010.0020.0060.991
Percentage of ProbabilityofFunding0.0100.0100.0100.0100.0100.0100.0100.0

srt:Minimum, cbsh:MortgageLoanCommitments


Probabilityof
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312019-09-302019-06-302019-03-31
Value-1.169.4-2.058.2540.0180.044-0.0920.508
Percentage of ProbabilityofFunding0.069.4200.059.01800.02200.0-1533.351.3

srt:WeightedAverage, cbsh:MortgageLoanCommitments


Probabilityof
Period End2021-06-302021-03-312020-12-312020-09-30
Value-2.188.81.683.289
Percentage of ProbabilityofFunding0.088.8-160.084.3

cbsh:ProceedsFromSaleOfOtherSecurities

cbsh:ProceedsFromSaleOfOtherSecurities


Proceeds
Period End2021-06-302021-03-312019-12-312019-09-302018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.7689.2920.0010.00.00.00.00.00.0510.5870.8980.098
Percentage of ProceedsFromSaleOfOtherSecurities100.0100.0100.00.00.00.00.00.0100.0100.0100.0100.0

cbsh:Proceedsfromsaleofequitysecurities

cbsh:Proceedsfromsaleofequitysecurities


Proceedsfromsaleofequitysecurities
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.00.00.00.0020.3973.4590.00.01.6560.0390.01510-0.5840.5840.0
Percentage of Proceedsfromsaleofequitysecurities0.00.00.0100.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.00.0

cbsh:Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities

cbsh:Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities


Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.7689.292283991740.002334.1792241505150.525431484233626.4540.098
Percentage of Proceedsfromsalesandmaturitiesofavailableforsaledebtequityandothersecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:PurchaseOfRiskParticipationAgreement

cbsh:PurchaseOfRiskParticipationAgreement


Purchase
Period End2021-06-302020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302015-12-312015-09-302014-12-312014-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value445000.00213000.0200000.026000.011000.050000.0070000.0000041000.0000000028000.000-275000.0
Percentage of PurchaseOfRiskParticipationAgreement100.00.0100.0100.0100.0100.0100.00.0100.00.00.00.00.0100.00.00.00.00.00.00.00.0100.00.00.0100.0

cbsh:PurchaseOfRiskParticipationAgreement us-gaap:FairValueByAssetClass

cbsh:DerivativeLevelThreeUnobservableInputs


Purchase
Period End2021-06-302020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302015-12-312015-09-302014-12-312014-09-302013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value445000.00213000.0200000.026000.011000.050000.0070000.0000041000.0000000028000.000-275000.0
Percentage of PurchaseOfRiskParticipationAgreement100.00.0100.0100.0100.0100.0100.00.0100.00.00.00.00.0100.00.00.00.00.00.00.00.0100.00.00.0100.0

cbsh:SaleOfRiskParticipationAgreement

cbsh:SaleOfRiskParticipationAgreement


Sale
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value32000.098000.000369000.0440000.0153000.0241000.073000.00031000.00148000.091000.0000-327000.033000.0036000.0-28000.000000-214000.0-107000.0-40000.0-41000.0-31000.00-40000.0-68000.0000-275000.0-76000.00-21000.0
Percentage of SaleOfRiskParticipationAgreement100.0100.00.00.0100.0100.0100.0100.0100.00.00.0100.00.0100.0100.00.00.00.0100.0100.00.0100.0100.00.00.00.00.00.0100.0100.0100.0100.0100.00.0100.0100.00.00.00.0100.0100.00.0100.0

cbsh:SaleOfRiskParticipationAgreement us-gaap:FairValueByAssetClass

cbsh:DerivativeLevelThreeUnobservableInputs


Sale
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-312011-09-30
Value32000.098000.000369000.0440000.0153000.0241000.073000.00031000.00148000.091000.0000-327000.033000.0036000.0-28000.000000-214000.0-107000.0-40000.0-41000.0-31000.00-40000.0-68000.0000
Percentage of SaleOfRiskParticipationAgreement100.0100.00.00.0100.0100.0100.0100.0100.00.00.0100.00.0100.0100.00.00.00.0100.0100.00.0100.0100.00.00.00.00.00.0100.0100.0100.0100.0100.00.0100.0100.00.00.00.0

cbsh:SalesAndRepaymentsOfPrivateEquitySecurities

cbsh:SalesAndRepaymentsOfPrivateEquitySecurities


Sales
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-03-312010-12-312010-09-30
Value0.3568.4760.00.2950.00.0690.3980.06.150.00.1850.00.1660.020.7810.291.550.0-24.1843.3152.398-14.0040.04.80.0-63.8870.0-31.409-0.014-5.6810.0-7.1840.0-0.858-1.614-7.845-2.434-6.726-1.1210.043-0.547-0.271
Percentage of SalesAndRepaymentsOfPrivateEquitySecurities100.0100.00.0100.00.0100.0100.00.0100.00.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.00.0100.00.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:SalesAndRepaymentsOfPrivateEquitySecurities us-gaap:FairValueByAssetClass

us-gaap:PrivateEquityFunds


Sales
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value0.3568.4760.00.2950.00.0690.3980.06.150.00.1850.00.1660.020.7810.291.550.0-24.1843.3152.398-14.0040.04.80.0-63.8870.0-31.409-0.014-5.6810.0-7.1840.0-0.858-1.614-7.845-2.434-6.726-1.121
Percentage of SalesAndRepaymentsOfPrivateEquitySecurities100.0100.00.0100.00.0100.0100.00.0100.00.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.00.0100.00.0100.0100.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsVestedInPeriodWeightedAverageGrantDateFairValue

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsVestedInPeriodWeightedAverageGrantDateFairValue


Share
Period End2021-06-302021-03-31
Value0.143.2
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsNonvestedShareAwardsVestedInPeriodWeightedAverageGrantDateFairValue100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod


Share
Period End2021-06-302021-03-312020-12-31
Value5835.0208440.045949.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriod100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value0.1139.48-1.09
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedInPeriodWeightedAverageExercisePrice100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod


Share
Period End2021-06-302021-03-312020-12-31
Value244.036.0426.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriod100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value0.7857.17-5.37
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpiredInPeriodWeightedAverageExercisePrice100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value2.1557.04-2.88
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriodWeightedAverageExercisePrice100.0100.0100.0

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice

cbsh:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice


Share
Period End2021-06-302021-03-312020-12-31
Value072.91-3.01
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageExercisePrice0.0100.0100.0

cbsh:ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue

cbsh:ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue


Share
Period End2021-06-302021-03-31
Value0.1856.66
Percentage of ShareBasedCompensationForfeitedNonvestedShareAwardWeightedAverageGrantDateFairValue100.0100.0

cbsh:ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue

cbsh:ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue


Share
Period End2021-06-302021-03-31
Value0.1271.97
Percentage of ShareBasedCompensationGrantedNonvestedShareAwardWeightedAverageGrantDateFairValue100.0100.0

cbsh:SuppliesPostageAndCommunication

cbsh:SuppliesPostageAndCommunication


Supplies
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.0334.1254.1934.1414.4274.6584.8515.1065.2755.1625.0955.1035.1265.3136.1185.5175.4465.7095.6455.9685.6936.8296.5545.6095.2265.5815.9455.3025.4865.6995.6765.4495.7975.5895.6415.45.6675.6135.555.6745.6925.5326.2226.7246.8297.338
Percentage of SuppliesPostageAndCommunication100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements

cbsh:TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value167.3588.3622.893-4.683-13.494-0.1871.945-1.051-1.5271.3124.2173.9554.472.035-5.3050.017-2.3142.344-2.785-2.814-0.441-1.674-1.1720.8873.6813.9213.204-4.76516-2.3010.9160.367-1.719-3.852.7751.4824.1143.6143.3052.61.0621.4291.539-0.12
Percentage of TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements us-gaap:IncomeStatementLocation

cbsh:InvestmentSecuritiesGainsLosses


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value168.3658.0132.389-7.497-13.0080.2712.02-1.176-1.8421.4784.2753.7914.3052.195-5.1980.048-2.8782.906-2.921-2.81-0.914-1.552-1.2210.8753.33.9763.225-4.85816-2.3590.8650.298-1.775-3.8692.7741.4754.125
Percentage of TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements102.6113.795.882.6160.196.4-144.9103.9111.9120.6112.7101.495.996.3107.998.0282.4124.4124.0104.999.9207.392.7104.298.689.6101.4100.7102.099.4102.594.481.2103.3100.5100.099.5100.3

cbsh:LoansFeesAndSales


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.035-1.3720.0890.5912.547-0.459-0.364-0.1120.1120.287-0.143-0.0510.1470.002-0.176-0.115-0.0320.554-0.5260.0860.0190.508-0.1880.106-0.0630.4080.00.00.00.00.00.00.00.00.00.00.0-0.009
Percentage of TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements-0.2-18.61.120.4-54.43.4194.7-5.8-10.7-18.8-10.9-1.23.70.0-8.62.2-188.2-23.9-22.4-3.1-0.7-115.211.2-9.0-7.111.10.00.0-0.00.0-0.00.00.0-0.0-0.00.00.0-0.2

cbsh:OtherNonInterestIncome


Total
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-0.3850.3650.26-0.0870.267-0.027-0.0940.0370.0130.028-0.023-0.0070.0170.1630.0160.0080.0010.01-0.0360.05-0.023-0.0350.066-0.0570.075-0.027-0.055-0.0210.0930.1050.0580.0510.0690.0560.0190.0010.007-0.002
Percentage of TotalGainsOrLossesIncludedInEarningsLevel3FairMeasurements-2.45.03.1-3.0-5.70.250.31.9-1.2-1.8-1.8-0.20.43.60.8-0.25.9-0.4-1.5-1.80.87.9-3.94.98.5-0.7-1.4-0.7-2.00.6-2.55.618.8-3.3-0.50.00.5-0.0

cbsh:Trustfeerevenue

cbsh:Trustfeerevenue


Trustfeerevenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4644414037394039383737373736
Percentage of Trustfeerevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:UnobservableInputDiscountRate us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:UnobservableInputDiscountRate

srt:Maximum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.029.36-0.039.2063-0.02130.115
Percentage of UnobservableInputDiscountRate100.0100.0100.0100.0100.0100.0

srt:Minimum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.019.03-0.019.06850.00060.0909
Percentage of UnobservableInputDiscountRate50.096.533.398.5-2.879.0

srt:WeightedAverage, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.049.21-0.059.18690.00060.0925
Percentage of UnobservableInputDiscountRate200.098.4166.799.8-2.880.4

cbsh:UnobservableInputLoanServicingCostsDelinquentLoans us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:UnobservableInputLoanServicingCostsDelinquentLoans

srt:Maximum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0750.0000750.0
Percentage of UnobservableInputLoanServicingCostsDelinquentLoans0.0100.00.00.00.0100.0

srt:Minimum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0200.0000200.0
Percentage of UnobservableInputLoanServicingCostsDelinquentLoans0.026.70.00.00.026.7

cbsh:UnobservableInputLoanServicingCostsPerformingLoans us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:UnobservableInputLoanServicingCostsPerformingLoans

srt:Maximum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-1.073.00-1.0-7.080.0
Percentage of UnobservableInputLoanServicingCostsPerformingLoans100.0100.00.0100.0100.0100.0

srt:Minimum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value070.000071.0
Percentage of UnobservableInputLoanServicingCostsPerformingLoans-0.095.90.0-0.0-0.088.8

srt:WeightedAverage, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-1.072.00-1.01.072.0
Percentage of UnobservableInputLoanServicingCostsPerformingLoans100.098.60.0100.0-14.390.0

cbsh:UnobservableInputPrepaymentSpeed us-gaap:Range, us-gaap:FairValueByAssetClass

cbsh:UnobservableInputPrepaymentSpeed

srt:Maximum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.914.110.0514.657-0.00050.1434
Percentage of UnobservableInputPrepaymentSpeed100.0100.0100.0100.0100.0100.0

srt:Minimum, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.1110.350.0313.0890.02170.1091
Percentage of UnobservableInputPrepaymentSpeed-12.273.460.089.3-4340.076.1

srt:WeightedAverage, cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.3112.42014.4390.00960.1314
Percentage of UnobservableInputPrepaymentSpeed34.488.00.098.5-1920.091.6

cbsh:UnobservableInputsLoanServicingCostsLoansInForeclosure us-gaap:FairValueByAssetClass

cbsh:UnobservableInputsLoanServicingCostsLoansInForeclosure

cbsh:MortgageServicingRights


Unobservable
Period End2021-06-302021-03-312020-12-31
Value01000.00
Percentage of UnobservableInputsLoanServicingCostsLoansInForeclosure0.0100.00.0

us-gaap:AccretionAmortizationOfDiscountsAndPremiumsInvestments

us-gaap:AccretionAmortizationOfDiscountsAndPremiumsInvestments


Accretion
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-19191000.0-22079000.0-22240000.0-11958000.0-15303000.0-10362000.0-7195000.0-7611000.0-2827000.0-9998000.0-7466000.0-7079000.0-4446000.0-7233000.0-7250000.0-10346000.0-8596000.0-9231000.0-8136000.0-7343000.0-4826000.0-11188000.0-9369000.0-5452000.0-2698000.0-15099000.0-8738000.0-6150000.0-1648000.0-6675000.0-7579000.0-5613000.0-4688000.0-12539000.0-6249000.0-13127000.0-4875000.0-11987000.0-9566000.0-6993000.0300000.0-2713000.0-4800000.0-8083000.0-3289000.0-5463000.0
Percentage of AccretionAmortizationOfDiscountsAndPremiumsInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BrokerageCommissionsRevenue

us-gaap:BrokerageCommissionsRevenue


Brokerage
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value4.5034.0813.9964.0113.0114.0774.1394.033.8883.7474.1843.8843.9713.7683.5763.6793.7263.6493.4093.3753.4913.5093.1013.5473.3643.1882.7682.7833.2463.873.1953.2423.3054.3914.0755.115.016.8714.5915.5564.9794.72
Percentage of BrokerageCommissionsRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value165172650-260.638918-8.29423-77.075355-602.808404257-37.3556073-9.397-246.865
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockDividendsPerShareCashPaid

us-gaap:CommonStockDividendsPerShareCashPaid


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.2630.2630.2190.270.270.270.210.260.260.260.190.2240.2240.2350.1820.2250.2250.2250.1820.2250.2250.2250.1820.2250.2250.2250.1820.2250.2250.2250.1820.2250.2250.2251.6150.230.230.230.1860.230.230.230.2240.2230.2240.224
Percentage of CommonStockDividendsPerShareCashPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleRealizedGain us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleRealizedGain

us-gaap:AvailableforsaleSecurities


Debt
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value4.131133.2910.00.0670.0380.8631.3860.0180.0070.2110.212
Percentage of DebtSecuritiesAvailableForSaleRealizedGain100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-651000.0-651000.0-551000.0-503000.0-542000.0-542000.0-531000.0-586000.0-585000.0-586000.0-491000.0-592000.0-592000.0-592000.0-449000.0-630000.0-617000.0-617000.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value-68000.0-68000.0-68000.0-67000.0-68000.0-68000.0-68000.0-68000.0-67000.0-68000.0-68000.0-68000.0-67000.0-68000.0-68000.0-67000.0-68000.0-68000.0-68000.0-68000.0-67000.0-68000.0-68000.0-203000.00000
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value1124000.01124000.01303000.01317000.01297000.01297000.01253000.01196000.01197000.01196000.01313000.01067000.01438000.01437000.01446000.01463000.01438000.01438000.01438000.01437000.01439000.01437000.01523000.01523000.01523000.01523000.01602000.01561000.01561000.01561000.01646000.01613000.01608000.01609000.01243000.01645000.01645000.01645000.0-1000.03378000.01675000.01675000.01694000.01640000.01640000.0
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:DefinedBenefitPlanInterestCost


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value556000.0556000.0819000.0818000.0823000.0822000.01003000.01065000.01065000.01065000.0939000.0916000.0951000.0950000.0957000.0923000.0973000.0973000.0986000.0986000.01005000.0967000.01191000.01139000.01216000.01216000.01284000.01262000.01262000.01261000.01130000.01134000.01123000.01122000.01302000.01287000.01286000.01287000.037000.02605000.01362000.01362000.01351000.01420000.01367000.0
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value109000.0110000.0114000.030000.0101000.0100000.0343000.0546000.0545000.0546000.0268000.0500000.0190000.0190000.063000.0216000.0212000.0213000.0199000.0263000.0279000.0246000.0348000.0200000.0473000.0474000.01975000.0193000.0194000.0193000.0383000.0420000.0412000.0412000.01016000.0475000.0475000.0475000.0190000.0174000.0315000.0315000.0331000.0530000.0477000.0
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:DefinedBenefitPlanServiceCost


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value94000.095000.0115000.093000.0101000.0101000.0130000.0159000.0159000.0159000.0219000.0127000.0152000.0153000.0171000.0193000.0128000.0129000.094000.0135000.0138000.0133000.0124000.0127000.0126000.0126000.031000.0133000.0133000.0133000.0114000.0132000.0131000.0132000.0194000.0103000.0104000.0103000.0104000.0126000.088000.088000.0166000.0184000.0183000.0
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationAmortizationAndAccretionNet

us-gaap:DepreciationAmortizationAndAccretionNet


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1111111110101010109.9669.8559.6449.569.62109.6319.871109.932101010101010101010101010101010101010111111111112121212
Percentage of DepreciationAmortizationAndAccretionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred

cbsh:MonetizedInterestRateFloor


Derivative
Period End2021-06-302021-03-312020-12-31
Value-6.011733
Percentage of DerivativeInstrumentsGainLossReclassificationFromAccumulatedOCIToIncomeEstimatedNetAmountToBeTransferred100.0100.0100.0

us-gaap:DividendsCommonStockCash

us-gaap:DividendsCommonStockCash


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value303030303030272728282425252522222222212121212020212120202121202020201502020201919202019191919
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Dividends
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value303030303030272728282425252522222222212121212020212120202121202020201502020201919202019191919
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsPreferredStockCash

us-gaap:DividendsPreferredStockCash


Dividends
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.0
Percentage of DividendsPreferredStockCash0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsPreferredStockCash us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Dividends
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-31
Value02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.02250000.0
Percentage of DividendsPreferredStockCash0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquipmentExpense

us-gaap:EquipmentExpense


Equipment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4.6054.3534.5264.7374.7554.8214.8594.9414.794.4714.5084.5924.5944.4314.6924.4914.7764.6094.8844.8424.7814.6344.9154.7894.6794.7034.7534.5934.5254.5044.5974.4654.684.6834.9834.9764.9995.1895.5835.395.7025.5775.7765.7095.9385.901
Percentage of EquipmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquitySecuritiesFvNiRealizedGain us-gaap:FinancialInstrument

us-gaap:EquitySecuritiesFvNiRealizedGain

us-gaap:EquitySecurities


Equity
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.00.00.00.0020.3972.8650.00.01.6570.00.0880.014
Percentage of EquitySecuritiesFvNiRealizedGain0.00.00.0100.0100.0100.00.00.0100.00.0100.0100.0

us-gaap:EquitySecuritiesFvNiUnrealizedGainLoss us-gaap:FinancialInstrument

us-gaap:EquitySecuritiesFvNiUnrealizedGainLoss

us-gaap:EquitySecurities


Equity
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-30
Value50000.0-35000.092000.077000.0-295000.056000.0
Percentage of EquitySecuritiesFvNiUnrealizedGainLoss100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-16.246-7.358-8.362-2.8934.683130.187-1.9451.0511.527-1.312-4.217-3.955-4.47-2.0355.305-0.017-2.3142.344-2.785-2.814-0.441-1.674-1.1720.8873.68134-3.204-4.76516-2.3010.9160.367-1.719-3.852.7751.4824.114
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 us-gaap:FairValueByAssetClass

cbsh:DerivativeLevelThreeUnobservableInputs


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.421.007-0.349-0.504-2.8140.4860.4580.075-0.125-0.3150.1660.058-0.164-0.1650.160.1070.0310.564-0.5620.136-0.0040.473-0.1220.0490.0120.3810.2990.0210.0930.1050.0580.0510.0690.0560.0190.0010.007-0.011
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1-2.6-13.74.217.4-60.13.6244.9-3.9-11.9-20.6-12.7-1.44.13.7-7.92.0-182.4-24.4-24.0-4.90.1-107.37.3-4.21.410.40.9-0.7-2.00.6-2.55.618.8-3.3-0.50.00.5-0.3

us-gaap:PrivateEquityFunds


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-16.666-8.365-8.013-2.3897.49713-0.271-2.021.1761.842-1.478-4.275-3.791-4.305-2.1955.198-0.048-2.8782.906-2.921-2.81-0.914-1.552-1.2210.8753.334-3.225-4.85816-2.3590.8650.298-1.775-3.8692.7741.4754.125
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1102.6113.795.882.6160.196.4-144.9103.9111.9120.6112.7101.495.996.3107.998.0282.4124.4124.0104.999.9207.392.7104.298.689.699.1100.7102.099.4102.594.481.2103.3100.5100.099.5100.3

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value18000.0-1000.099000.0271000.01123000.0-1495000.0-48000.0-65000.0-5000.0-364000.0-195000.0167000.0-379000.0-133000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss us-gaap:FairValueByAssetClass

us-gaap:USStatesAndPoliticalSubdivisions


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value18000.0-1000.099000.0271000.01123000.0-1495000.0-48000.0-65000.0-5000.0-364000.0-195000.0167000.0-379000.0-133000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAccruedInterestWriteoff us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableAccruedInterestWriteoff

cbsh:PersonalBankingPortfolioSegment


Financing
Period End2021-06-302021-03-312020-03-31
Value1100000.02000000.01900000.0
Percentage of FinancingReceivableAccruedInterestWriteoff100.0100.0100.0

us-gaap:CommercialPortfolioSegment


Financing
Period End2021-06-302021-03-312020-03-31
Value36000.0125000.054000.0
Percentage of FinancingReceivableAccruedInterestWriteoff3.36.22.8

us-gaap:FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery

us-gaap:FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.6999.9528.0167.5848.410
Percentage of FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery us-gaap:FinancingReceivablePortfolioSegment

cbsh:PersonalBankingPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value5.6939.9357.4447.395.15711
Percentage of FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery814.499.892.997.461.4103.6

us-gaap:CommercialPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-4.9940.0170.5720.1943.243-0.394
Percentage of FinancingReceivableAllowanceForCreditLossWriteoffAfterRecovery-714.40.27.12.638.6-3.6

us-gaap:FinancingReceivableAllowanceForCreditLossesRecovery

us-gaap:FinancingReceivableAllowanceForCreditLossesRecovery


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value8.1692.9895.7453.0652.8453.534
Percentage of FinancingReceivableAllowanceForCreditLossesRecovery100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesRecovery us-gaap:FinancingReceivablePortfolioSegment

cbsh:PersonalBankingPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value2.9052.7742.6142.9022.7022.724
Percentage of FinancingReceivableAllowanceForCreditLossesRecovery35.692.845.594.795.077.1

us-gaap:CommercialPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value5.2640.2153.1310.1630.1430.81
Percentage of FinancingReceivableAllowanceForCreditLossesRecovery64.47.254.55.35.022.9

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value8.8681213101114
Percentage of FinancingReceivableAllowanceForCreditLossesWriteOffs100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesWriteOffs us-gaap:FinancingReceivablePortfolioSegment

cbsh:PersonalBankingPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value8.5981210107.85913
Percentage of FinancingReceivableAllowanceForCreditLossesWriteOffs97.098.273.196.669.997.1

us-gaap:CommercialPortfolioSegment


Financing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.270.2323.7030.3573.3860.416
Percentage of FinancingReceivableAllowanceForCreditLossesWriteOffs3.01.826.93.430.12.9

us-gaap:GainLossOnDerivativeInstrumentsNetPretax us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation

us-gaap:GainLossOnDerivativeInstrumentsNetPretax

cbsh:CreditRiskParticipationAgreements, us-gaap:Nondesignated, cbsh:OtherNonInterestIncome


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-385000.0365000.0260000.0-87000.0267000.0-27000.0-94000.037000.013000.028000.0-23000.0-7000.016000.0164000.017000.07000.01000.010000.0-36000.050000.0-23000.0-35000.066000.0-57000.075000.0-27000.0-55000.0-21000.093000.0105000.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

cbsh:MortgageLoanCommitments, us-gaap:Nondesignated, cbsh:LoansFeesAndSales


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-35000.0-1372000.090000.0589000.02548000.0-459000.0-364000.0-112000.0112000.0287000.0-144000.0-50000.0148000.01000.0-177000.0-114000.0-32000.0554000.0-526000.086000.019000.0508000.0-188000.0106000.0-63000.0408000.00000
Percentage of GainLossOnDerivativeInstrumentsNetPretax9.1-375.934.6-677.0954.31700.0387.2-302.7861.51025.0626.1714.3925.00.6-1041.2-1628.6-3200.05540.01461.1172.0-82.6-1451.4-284.8-186.0-84.0-1511.1-0.0-0.00.00.0

cbsh:MortgageLoanForwardSaleContracts, us-gaap:Nondesignated, cbsh:LoansFeesAndSales


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-11000.039000.0-23000.020000.03000.0-4000.0-4000.0-2000.0-13000.016000.0-1000.006000.00-6000.08000.0-4000.066000.0-64000.01000.01000.0-1000.05000.0-6000.04000.0-3000.00000
Percentage of GainLossOnDerivativeInstrumentsNetPretax2.910.7-8.8-23.01.114.84.3-5.4-100.057.14.3-0.037.50.0-35.3114.3-400.0660.0177.82.0-4.32.97.610.55.311.1-0.0-0.00.00.0

us-gaap:ForeignExchangeContract, us-gaap:Nondesignated, cbsh:OtherNonInterestIncome


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value-12000.096000.0-29000.00-44000.0-38000.055000.0-5000.0-13000.016000.0-31000.0-120000.0173000.09000.0-56000.051000.0-55000.0-20000.067000.0-20000.057000.0-49000.0-14000.0-55000.0761000.0-439000.0-397000.0176000.0128000.0-170000.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax3.126.3-11.2-0.0-16.5140.7-58.5-13.5-100.057.1134.81714.31081.25.5-329.4728.6-5500.0-200.0-186.1-40.0-247.8140.0-21.296.51014.71625.9721.8-838.1137.6-161.9

us-gaap:ForwardContracts, us-gaap:Nondesignated, cbsh:LoansFeesAndSales


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-31
Value-1046000.02906000.0-958000.0-709000.0-153000.0380000.0-18000.0-1412000.0859000.0-266000.0-232000.0113000.0-9000.0542000.0-68000.0-322000.0-160000.0-98000.0-172000.0-397000.0-329000.0-370000.0390000.0-5000.0000
Percentage of GainLossOnDerivativeInstrumentsNetPretax271.7796.2-368.5814.9-57.3-1407.419.1-3816.26607.7-950.01008.7-1614.3-56.2330.5-400.0-4600.0-16000.0-980.0-344.01726.1940.0649.1520.018.5-0.00.00.0

us-gaap:InterestRateCap, us-gaap:Nondesignated, cbsh:OtherNonInterestIncome


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312015-12-312015-09-302014-12-312014-09-30
Value015000.001000.0019000.00032000.0020000.013000.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax-0.04.10.0-1.10.0-70.40.00.048.5-0.0-36.4-61.9

us-gaap:InterestRateSwap, us-gaap:Nondesignated, cbsh:OtherNonInterestIncome


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value875000.01075000.0-52000.081000.022000.0266000.02086000.01519000.0824000.0303000.0990000.0692000.01727000.0505000.0677000.0702000.0456000.0143000.02729000.0203000.0769000.02226000.0758000.0741000.01627000.01183000.0651000.0212000.0366000.0445000.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax-227.3294.5-20.0-93.18.2-985.2-2219.14105.46338.51082.1-4304.3-9885.710793.8307.93982.410028.645600.01430.0-7580.6406.0-3343.5-6360.01148.5-1300.02169.3-4381.5-1183.6-1009.5393.5423.8

us-gaap:GainLossOnDerivativeInstrumentsNetPretax us-gaap:HedgingDesignation

us-gaap:Nondesignated


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value-614000.03124000.0-712000.0-105000.02643000.0137000.01661000.025000.01782000.0384000.0570000.0628000.02061000.01221000.0387000.0332000.0206000.0655000.03147000.0148000.0426000.02320000.0726000.0359000.02794000.01117000.0219000.0380000.0587000.0380000.0232000.0719000.0162000.0342000.0304000.093000.0235000.0-34000.037000.0180000.0151000.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax159.5855.9-273.8120.7989.9-507.4-1767.067.613707.71371.4-2478.3-8971.412881.2744.52276.54742.920600.06550.0-8741.7296.0-1852.2-6628.61100.0-629.83725.3-4137.0-398.2-1809.5631.2361.90.00.00.00.00.00.00.00.00.00.00.0

us-gaap:GainLossOnSaleOfLoansAndLeases

us-gaap:GainLossOnSaleOfLoansAndLeases


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6.2967.3818.1396.4410.0331.7932.2463.2972.6551.9291.62.0991.5241.1471.8082.6532.6810.8660.9261.932.0250.9690.8920.950.7670.4670.00.00.00.00.00.00.00.00.00.0010.0170.3580.4860.4070.5760.5713.7464.191.8970.569
Percentage of GainLossOnSaleOfLoansAndLeases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable

us-gaap:IncreaseDecreaseInAccruedIncomeTaxesPayable


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-9.012820-20.7844.857.992-9.065-0.063.11120-17.8194.3863.64522-27.886-1.282-19.673212.7221.714-26.06262.853-1.31-7.28224-4.536-9.839-15.69130-8.84613-33.61326-7.824-7.57-21.49723-0.3449.269-21.458276.228-11.112-10.92718
Percentage of IncreaseDecreaseInAccruedIncomeTaxesPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet

us-gaap:IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value380-160.273445-87.374312-422.759209-753.02671-233.6389469534-374.80998152-64.705-402.756234-142.381674-1006.164-229.64552755-252.055467440227-269.406-413.83518949343-174.399-47.796182-133.093198-224.742359-59.813-547.7286247.583-104.418
Percentage of IncreaseDecreaseInFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchaseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInInterestAndDividendsReceivable

us-gaap:IncreaseDecreaseInInterestAndDividendsReceivable


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-6.244-0.4442.3877.341.9911.681-3.0870.647-2.4441.568-0.7633.3042.461-0.7440.7023.329-0.2580.6863.3110.391-0.5330.4732.342.034-0.170.788-0.032.319-1.5251.421-0.54-2.578-0.1210.0051.579-0.233-0.67-3.8250.933-0.0182.34-1.24513-2.1660.4750.037
Percentage of IncreaseDecreaseInInterestAndDividendsReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInInterestPayableNet

us-gaap:IncreaseDecreaseInInterestPayableNet


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-1005000.0-1804000.0-1774000.0-2525000.0-2984000.0-2161000.0-352000.01517000.01713000.02708000.01448000.01290000.0131000.0-732000.0261000.0469000.0-731000.039000.0838000.0212000.0-223000.0280000.0432000.0105000.0-228000.027000.047000.0-266000.0-36000.025000.0-250000.0-1081000.0-484000.0246000.0-205000.0-882000.0-299000.0114000.0-205000.0-1707000.0-2755000.069000.0-2830000.0-2803000.0-1708000.0-2121000.0
Percentage of IncreaseDecreaseInInterestPayableNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInTimeDeposits

us-gaap:IncreaseDecreaseInTimeDeposits


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-25.436-73.0-145.756-43.266259-233.664-61.208-32.701225218-13.836-11.011-73.934-9.961-49.582-267.095-331.419174228-252.829-150.8384186.082-41.542-101.9712-40.661-269.99784167-163.462-199.819-29.68310221-202.16-312.92635-105.258-88.176-224.963162-182.379-261.529263-289.019
Percentage of IncreaseDecreaseInTimeDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInTradingSecurities

us-gaap:IncreaseDecreaseInTradingSecurities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.585-4.8726.406-0.387-21.35616-4.2914.0151.045-4.6329.391-18.9575.318-0.351-1.1371.666-7.7633.4823.922-5.041-76.143813.732-3.0514.361-1.452.29-0.248-16.59714-8.5122.144-9.60915-9.46-7.29411-5.2952.5672.383-2.009-14.973133.018-0.897
Percentage of IncreaseDecreaseInTradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements cbsh:IncomePerCommonShare

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

cbsh:DilutedIncomePerCommonShare


Incremental
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value287000.0313000.015000.0179000.0190000.0258000.012000.0254000.0265000.0290000.00353000.0343000.0332000.014000.0336000.0344000.0397000.032000.0243000.0249000.0216000.05000.0280000.0322000.0299000.01000.0393000.0384000.0421000.045000.0449000.0375000.0233000.0-22000.0313000.0282000.0352000.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InformationTechnologyAndDataProcessing

us-gaap:InformationTechnologyAndDataProcessing


Information
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value24252423232323232322222221202322232323232222222121192019191919191918181918171716171616161716
Percentage of InformationTechnologyAndDataProcessing100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestAndDividendIncomeOperating

us-gaap:InterestAndDividendIncomeOperating


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value211209214223213221226231238227232224225205201194193187181179180172169169170152158161167159162162167158170163174169173170178175177178185188
Percentage of InterestAndDividendIncomeOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestAndDividendIncomeSecurities

us-gaap:InterestAndDividendIncomeSecurities


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value55515260505358586455615965535350545551515448495053384346534544465344534657535551575453505355
Percentage of InterestAndDividendIncomeSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldForSale

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldForSale


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value245000.0304000.0272000.0264000.0127000.0197000.0206000.0308000.0361000.0334000.0307000.0315000.0372000.0304000.0254000.0287000.0263000.0196000.0156000.0334000.0692000.0135000.083000.048000.039000.021000.00000
Percentage of InterestAndFeeIncomeLoansAndLeasesHeldForSale100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio

us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value144146150150151159161167167166164159154147142138134128125123121119116114113111112112111110112110108107110111112111113114116118121126128130
Percentage of InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase

us-gaap:InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.320.3120.330.4060.5854.775.5768.2738.0577.5096.6765.0223.9564.0013.4062.8462.0381.5390.9780.7240.7250.8880.590.4830.4210.3670.2660.2870.2630.2030.1550.1660.270.2180.1850.2210.1770.2250.140.2920.6870.6220.3540.5840.8260.82
Percentage of InterestExpenseFederalFundsPurchasedAndSecuritiesSoldUnderAgreementsToRepurchase100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits

us-gaap:InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1.8442.1032.3593.2063.9778.3099.63110109.6028.4657.236.5195.5894.6364.4414.3423.893.7153.6193.5483.4843.4233.3563.2873.3083.4583.43.3583.3063.5543.5023.3753.9244.3444.6234.6345.0816.1396.4456.3726.97.237.2617.7117.096
Percentage of InterestExpenseNOWAccountsMoneyMarketAccountsAndSavingsDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseTimeDeposits100000OrMore

us-gaap:InterestExpenseTimeDeposits100000OrMore


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.6611.0621.5912.5123.615.2356.4727.546.9316.0024.4373.8993.4832.8392.492.7842.8222.7632.0262.1862.3471.9861.5831.5541.5041.411.4411.5181.5151.4521.4821.5351.6671.6991.6921.7431.8281.9112.0352.132.4342.6732.9013.4613.5623.923
Percentage of InterestExpenseTimeDeposits100000OrMore100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseTimeDepositsLessThan100000

us-gaap:InterestExpenseTimeDepositsLessThan100000


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.3270.4730.7011.0281.3931.7751.8381.741.5311.2591.0250.8340.6940.6620.6510.6760.6740.6440.6750.6830.7090.7420.7520.7860.8180.880.9441.011.0631.121.2171.381.6561.7491.8631.9452.0042.1062.2312.4132.9653.7434.5535.4446.0596.815
Percentage of InterestExpenseTimeDepositsLessThan100000100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeDepositsWithFinancialInstitutions

us-gaap:InterestIncomeDepositsWithFinancialInstitutions


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value743000.0370000.0277000.0261000.0443000.01292000.01585000.01241000.01986000.01886000.02025000.01478000.01590000.01140000.0802000.0662000.0362000.0397000.0284000.0268000.0151000.0270000.0124000.0103000.0122000.0179000.0296000.071000.088000.0100000.0164000.071000.075000.077000.0132000.040000.0112000.055000.076000.0211000.0110000.090000.055000.0106000.0201000.065000.0
Percentage of InterestIncomeDepositsWithFinancialInstitutions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value253211214212122143187192199191199197200182177171172167162163162154153153156141147147152143149150152147152148159151149147152145139137140128
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell

us-gaap:InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell


Interest
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value2000.01000.0002000.04000.07000.011000.033000.093000.069000.0177000.0180000.092000.078000.037000.023000.015000.020000.019000.024000.015000.021000.015000.09000.021000.030000.024000.026000.0
Percentage of InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LaborAndRelatedExpense

us-gaap:LaborAndRelatedExpense


Labor
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value13012912912712612812612312012212011611511511511110811210810710410610210099989995949495918990948987898885848786858787
Percentage of LaborAndRelatedExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LeaseIncome

us-gaap:LeaseIncome


Lease
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value7.7258.1958.3798.7078.4648.4198.2098.0767.967.768
Percentage of LeaseIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:MarketingExpense

us-gaap:MarketingExpense


Marketing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value5.685.1585.0284.9263.8015.9793.9516.0486.0155.95.6024.9995.1424.8053.9374.6764.4883.2243.4314.3994.3893.8133.5394.3434.3073.9183.9724.0743.9493.6812.9213.8484.0483.3592.7154.14.4693.8223.4694.5454.4954.2583.3775.0645.0024.718
Percentage of MarketingExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestExpense

us-gaap:NoninterestExpense


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value198192196190187193195191189191188185181182213184184186181181177177175171165163170162162162161156156155158153156150156153153153164155155155
Percentage of NoninterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestExpense us-gaap:StatementBusinessSegments

cbsh:CommercialSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value827978787880777678767573757271717473727170696868656465626261605759
Percentage of NoninterestExpense41.741.240.141.041.741.839.539.841.540.140.339.841.439.933.538.740.139.540.139.440.039.339.040.139.739.538.238.838.238.037.436.537.6

cbsh:ConsumerSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value737071737577747376737471727073727371727070686969676667666764666668
Percentage of NoninterestExpense37.336.636.638.340.339.937.938.740.138.439.338.539.638.534.239.339.938.339.938.739.838.939.840.440.940.739.641.241.440.041.242.843.9

cbsh:OtherElimination


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value7.5129.745138.4883.6013.68212103.748107.5729.7534.1517.449389.9697.491117.451117.45109.9966.1455.0155.148118.769.327109.6858.6745.276
Percentage of NoninterestExpense3.85.17.14.41.91.96.55.52.05.34.05.32.34.118.25.44.16.04.16.44.25.75.73.63.03.16.95.45.76.56.05.53.4

cbsh:SegmentTotals


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value190182182182183190182180186181181175177174174174177175173169169167165165160158158153153151151147151
Percentage of NoninterestExpense96.294.992.995.698.198.193.594.598.094.796.094.797.795.981.894.695.994.095.993.695.894.394.396.497.096.993.194.694.393.294.094.596.6

cbsh:WealthSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value343331313031313031303130303130302930282828282727272726232324242323
Percentage of NoninterestExpense17.217.216.216.216.116.416.116.016.416.116.416.416.617.514.116.516.016.215.815.616.016.115.515.916.316.715.314.714.715.315.415.215.1

us-gaap:NoninterestIncome

us-gaap:NoninterestIncome


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1391361351291171231431321271211331231241191241221231171191191161191151111141061121121081021091061029910310010094941011019511010010193
Percentage of NoninterestIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestIncome cbsh:NatureofRevenue

cbsh:RevenueNotInScopeofASC606


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value14191716137.03511109.5699.2036.7699.2719.8838.1148.419.3079.8088.66
Percentage of NoninterestIncome10.714.613.112.511.15.77.98.17.57.65.17.57.96.86.87.68.07.4

cbsh:RevenuefromContractswithCustomersInScopeofASC606


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value124116117113104116132121117112126114114111110107105100
Percentage of NoninterestIncome89.385.486.987.588.994.392.191.992.592.494.992.592.193.289.388.085.886.2

us-gaap:NoninterestIncome cbsh:NatureofRevenue, us-gaap:ProductOrService

cbsh:RevenuefromContractswithCustomersInScopeofASC606, cbsh:BankCardTransactionFees


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value423739373340414442394442434142393735
Percentage of NoninterestIncome30.627.729.629.228.732.528.633.533.532.733.434.334.634.634.532.030.330.5

cbsh:RevenuefromContractswithCustomersInScopeofASC606, cbsh:ConsumerBrokerageServices


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value4.5034.0813.9964.0113.0114.0774.1394.033.8883.7474.1843.8843.9713.7683.5763.6793.7263.649
Percentage of NoninterestIncome3.23.03.03.12.63.32.93.03.13.13.13.13.23.12.93.03.03.1

cbsh:RevenuefromContractswithCustomersInScopeofASC606, cbsh:DepositAccountChargesandOtherFees


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value232224232223242423232323232222222221
Percentage of NoninterestIncome17.216.617.917.819.019.117.418.118.819.017.919.219.119.218.218.518.618.7

cbsh:RevenuefromContractswithCustomersInScopeofASC606, cbsh:OtherNonInterestIncome


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value6.9627.6967.3227.5667.4438.709219.8098.8228.372166.9776.8527.3116.5067.4568.577.597
Percentage of NoninterestIncome5.05.75.45.86.37.015.17.46.96.912.25.65.56.15.26.17.06.5

cbsh:RevenuefromContractswithCustomersInScopeofASC606, cbsh:TrustFees


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value464441403739403938373737373635343332
Percentage of NoninterestIncome33.232.431.131.532.332.328.229.830.230.728.230.229.730.128.528.326.927.3

us-gaap:NoninterestIncome us-gaap:StatementBusinessSegments

cbsh:CommercialSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value525050474549525350475149514949474947504948514947494748474747494745
Percentage of NoninterestIncome37.637.337.637.039.140.336.540.339.539.539.140.241.441.140.139.240.440.342.041.841.442.942.742.743.544.742.942.543.745.945.044.743.9

cbsh:ConsumerSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value363841373634363633293231323035353431343433293230302629292825282928
Percentage of NoninterestIncome26.528.130.428.630.927.625.427.226.424.124.425.425.725.228.528.828.027.029.128.728.325.127.727.726.524.826.326.226.425.126.527.827.5

cbsh:OtherElimination


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value-2.526-3.916-5.977-3.165-9.304-7.726.932-3.178-1.671-0.1784.339-1.153-1.813-1.838-2.145-1.2580.0280.669-2.447-1.417-1.3783.6070.255-1.188-0.469-1.1061.2181.8281.013-0.2792.0730.246-0.465
Percentage of NoninterestIncome-1.8-2.9-4.4-2.4-7.9-6.24.8-2.4-1.3-0.13.3-0.9-1.5-1.5-1.7-1.00.00.6-2.0-1.2-1.23.00.2-1.1-0.4-1.01.11.60.9-0.31.90.2-0.5

cbsh:SegmentTotals


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value141139141132126131136135128121128124126121126123123116121120117115115112114107111110107102107106103
Percentage of NoninterestIncome101.8102.9104.4102.4107.9106.295.2102.4101.3100.196.7100.9101.5101.5101.7101.0100.099.4102.0101.2101.297.099.8101.1100.4101.098.998.499.1100.398.199.8100.5

cbsh:WealthSegment


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-30
Value525049474447474645444443424241403837363636343434343333333129292929
Percentage of NoninterestIncome37.737.536.436.837.938.333.335.035.436.633.235.434.435.233.233.131.632.230.930.731.428.929.430.630.431.529.729.729.029.226.627.329.0

us-gaap:NoninterestIncomeOther

us-gaap:NoninterestIncomeOther


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value3.3274.9813.8263.1943.7723.792.5361.7871.9441.8791.8431.5951.9922.2911.7431.7552.1562.3422.6792.7512.52.7253.1162.622.7383.0022.7682.7833.2463.87
Percentage of NoninterestIncomeOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestIncomeOtherOperatingIncome

us-gaap:NoninterestIncomeOtherOperatingIncome


Noninterest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11121210128.719261412121811111010111210119.8729.526149.5918.1879.9677.76310119.4167.921119.2399.1688.8969.0098.9719.2826.7426.7755.5196.7738.3656.977.0716.7388.44
Percentage of NoninterestIncomeOtherOperatingIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OccupancyNet

us-gaap:OccupancyNet


Occupancy
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11121112111112121111111111111111111111121111101110111111111111111111111111111111111211121112
Percentage of OccupancyNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal

us-gaap:OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal


Off
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-18.2224.1233.107-0.0993.04915
Percentage of OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal100.0100.0100.0100.0100.0100.0

us-gaap:OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal us-gaap:FinancingReceivablePortfolioSegment

cbsh:PersonalBankingPortfolioSegment


Off
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-0.059-0.131-0.16-0.0390.0580.48
Percentage of OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal0.3-3.2-5.139.41.93.2

us-gaap:CommercialPortfolioSegment


Off
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value-18.1634.2543.267-0.062.99114
Percentage of OffBalanceSheetCreditLossLiabilityCreditLossExpenseReversal99.7103.2105.160.698.196.8

us-gaap:OperatingLeaseLeaseIncome

us-gaap:OperatingLeaseLeaseIncome


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1930000.02074000.02098000.02270000.02160000.02061000.02135000.01984000.01926000.01906000.0
Percentage of OperatingLeaseLeaseIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingLeaseLeaseIncome cbsh:OperatingLeaseIncome

cbsh:OperatingLeaseIncomefromRelatedParty


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value19000.019000.019000.019000.019000.019000.019000.019000.018000.019000.0
Percentage of OperatingLeaseLeaseIncome1.00.90.90.80.90.90.91.00.91.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value74-211.569-8.1599.632133189-47.41945127101101-44.524-25.938-98.089-61.1422032-178.04-22.09950112-53.93726-70.073490.724-39.5747143-26.9735.624
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax cbsh:ComponentsOfOtherComprehensiveIncome

cbsh:UnrealizedGainLossOnSecuritiesOther


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value74-211.569-0.8514118104-28.008281029893-42.97-25.773-98.081-58.487412032-177.809-22.17350113-55.16227-69.8474916-38.8097143-42.3496.164
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax100.0100.010.4146.589.155.459.161.880.497.091.696.599.4100.095.799.0100.499.999.9100.3100.3100.7102.3102.099.7100.42236.698.1101.0100.2157.0109.6

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-1.205-4.4811484-18.68417253.02710-1.6250.00.00.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsBeforeTax14.8-46.510.944.639.439.119.93.09.83.6-0.0-0.0-0.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax

us-gaap:OtherComprehensiveIncomeLossBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value68-216.834-16.076-7.768128190-44.97147129102102-43.754-25.625-97.709-85.408401831-177.591-21.5250113-53.49427-69.24473.003-38.8447049-26.286.711-174.031-10.614-47.897473012
Percentage of OtherComprehensiveIncomeLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossBeforeTax cbsh:ComponentsOfOtherComprehensiveIncome

cbsh:PensionLoss


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value0.5830.583-5.6210.4360.4740.4740.0020.5180.5180.518-0.6870.5240.5250.524-2.1460.5630.5490.5490.3090.5790.5750.5832.1240.4570.6540.655-12.7450.3590.360.36160.7670.7660.767-11.6840.730.730.73
Percentage of OtherComprehensiveIncomeLossBeforeTax0.8-0.335.0-5.60.40.2-0.01.10.40.5-0.7-1.2-2.0-0.52.51.42.91.8-0.2-2.71.10.5-4.01.7-0.91.4-424.4-0.90.50.7-61.111.4-0.4-7.224.41.52.46.0

cbsh:UnrealizedGainLossOnSecuritiesOther


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value74-211.569-4.9810.44115104-27.065281029793-42.977-25.985-98.293-83.189391830-177.917-22.17350113-55.27527-70.1344716-38.8097048-42.4656.154-174.603-13.215-36.17140285.977
Percentage of OtherComprehensiveIncomeLossBeforeTax107.997.631.0-5.789.955.160.259.679.495.890.798.2101.4100.697.497.596.497.8100.2103.098.9100.1103.3100.3101.399.1539.299.999.698.7161.691.7100.3124.575.585.894.749.3

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-6.033-5.848-5.474-8.6441284-17.64218263.70510-1.3720.00.00.0
Percentage of OtherComprehensiveIncomeLossBeforeTax-8.82.734.1111.39.744.639.240.020.43.610.23.1-0.0-0.0-0.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax

us-gaap:InterestRateFloor, us-gaap:DesignatedAsHedgingInstrument


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-1.481-4.08718107-27.2323135100.00.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax us-gaap:HedgingDesignation

us-gaap:DesignatedAsHedgingInstrument


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-1.481-4.08718107-27.2323135100.00.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAndTax100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax

us-gaap:InterestRateFloor, us-gaap:DesignatedAsHedgingInstrument, cbsh:InterestandFeeIncomeonLoans


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value5.7995.5093.1860.7630.00.00.00.00.00.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax100.0100.0100.0100.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:HedgingDesignation

us-gaap:DesignatedAsHedgingInstrument


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value5.7995.5093.1860.7630.00.00.00.00.00.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax100.0100.0100.0100.00.00.00.00.00.00.0