WEC


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

Table of contents



us-gaap:CommonStockValue

us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostsAndExpenses
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:GainsLossesOnExtinguishmentOfDebt
us-gaap:SubsequentEventType

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxesPaidNet

us-gaap:InterestExpense
us-gaap:ConsolidationItems
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:InterestPaidNet
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:NetIncomeLoss

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:NonoperatingIncomeExpense
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:OperatingIncomeLoss
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:ProfitLoss
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:ProductOrService, wec:TypesofOperatingRevenues
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ConsolidationItems, wec:TypesofOperatingRevenues
us-gaap:MajorCustomers, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, wec:TypesofOperatingRevenues
us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues
us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues
wec:TypesofOperatingRevenues

us-gaap:Revenues
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues
us-gaap:ProductOrService, wec:TypesofOperatingRevenues
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues
wec:TypesofOperatingRevenues

us-gaap:Assets
dei:LegalEntity, us-gaap:ConsolidationItems
us-gaap:ConsolidatedEntities
us-gaap:ConsolidationItems
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementBusinessSegments
us-gaap:AwardType
us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ConsolidatedEntities
us-gaap:StockholdersEquity
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:CashAndCashEquivalentsAtCarryingValue
us-gaap:ConsolidatedEntities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:AccountsReceivableNetCurrent

us-gaap:OtherAssetsCurrent
us-gaap:ConsolidatedEntities

us-gaap:AssetsNoncurrent
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:PublicUtilityRegulatedOrUnregulatedStatus
us-gaap:ConstructionInProgressGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment
us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

us-gaap:PropertyPlantAndEquipmentNet
us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

us-gaap:Goodwill
us-gaap:StatementBusinessSegments
dei:LegalEntity
us-gaap:FiniteLivedIntangibleAssetsNet
dei:LegalEntity, us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:AccountsPayableCurrent
us-gaap:ConsolidatedEntities
us-gaap:AccruedLiabilitiesCurrent

us-gaap:LiabilitiesCurrent
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:LongTermDebtCurrent
us-gaap:ConsolidatedEntities
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherLiabilitiesCurrent
us-gaap:ConsolidatedEntities

us-gaap:LiabilitiesNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:LongTermDebt
us-gaap:ConsolidatedEntities, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementBasis

us-gaap:LongTermDebtNoncurrent
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
us-gaap:RetirementPlanType

us-gaap:OtherLiabilitiesNoncurrent
us-gaap:ConsolidatedEntities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive
us-gaap:BalanceSheetLocation
us-gaap:OperatingLeaseLiability

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount
us-gaap:ConsolidatedEntities
us-gaap:StockholdersEquity
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementEquityComponents

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:DepreciationDepletionAndAmortization
us-gaap:ConsolidationItems
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInAccountsPayable

us-gaap:IncreaseDecreaseInInventories

us-gaap:NetCashProvidedByUsedInOperatingActivities
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:NetIncomeLoss

us-gaap:ProfitLoss
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:PaymentsOfDividendsCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:EffectiveIncomeTaxRateContinuingOperations
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxAssetsNet

us-gaap:UnrecognizedTaxBenefits

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:AdjustmentForAmortization

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationConsiderationTransferred1

us-gaap:CapitalExpendituresIncurredButNotYetPaid
us-gaap:BusinessAcquisition
us-gaap:CashAcquiredFromAcquisition

us-gaap:CommonStockDividendsPerShareDeclared
us-gaap:SubsequentEventType
wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues
us-gaap:ContractWithCustomerLiabilityRevenueRecognized

us-gaap:DeferredIncomeTaxesAndTaxCredits
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanInterestCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:DerivativeGainLossOnDerivativeNet
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeNonmonetaryNotionalAmountEnergyMeasure

us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:SubsequentEventType
us-gaap:EarlyRepaymentOfSeniorDebt

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsOther

us-gaap:EquityMethodInvestmentDividendsOrDistributions
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:EquitySecuritiesFvNiUnrealizedGain

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements

us-gaap:IncomeLossFromEquityMethodInvestments
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:StatementBusinessSegments

us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions

us-gaap:IncomeTaxReconciliationChangeInEnactedTaxRate

us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

us-gaap:IncomeTaxReconciliationOtherAdjustments

us-gaap:IncomeTaxReconciliationStateAndLocalIncomeTaxes

us-gaap:IncomeTaxReconciliationTaxCreditsOther

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInOtherCurrentAssets

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:RegulatoryAsset
us-gaap:ProductOrService, us-gaap:RegulatoryAsset, us-gaap:StatementBusinessSegments
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:RegulatoryAsset
us-gaap:ConsolidatedEntities, us-gaap:DerivativeInstrumentRisk
us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding

us-gaap:NoncontrollingInterestIncreaseFromBusinessCombination
us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax

us-gaap:OtherCostAndExpenseOperating
us-gaap:ConsolidationItems
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsToAcquireAssetsInvestingActivities

us-gaap:PaymentsToAcquireInterestInSubsidiariesAndAffiliates
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:PensionAndOtherPostretirementBenefitContributions
us-gaap:RetirementPlanType

us-gaap:ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:ProceedsFromInsuranceSettlementInvestingActivities
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:ProceedsFromIssuanceOfDebt
dei:LegalEntity, us-gaap:DebtInstrument, us-gaap:RegulatoryAgency
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:SubsequentEventType

us-gaap:ProceedsFromLifeInsurancePolicies

us-gaap:ProceedsFromOtherShortTermDebt

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess

us-gaap:ProceedsFromSaleOfRestrictedInvestments

us-gaap:ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets

us-gaap:ProceedsFromStockOptionsExercised

us-gaap:ProvisionForDoubtfulAccounts
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesRequestedEquityCapitalStructurePercentage
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreaseAmount
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesRequestedRateIncreaseDecreasePercentage
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:RegulatoryAgency
us-gaap:PublicUtilitiesRequestedReturnOnEquityPercentage
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:RelatedPartyTransactionExpensesFromTransactionsWithRelatedParty

us-gaap:RepaymentsOfOtherShortTermDebt
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:RepaymentsOfSecuredDebt
us-gaap:ConsolidatedEntities, us-gaap:ShortTermDebtType
us-gaap:RepaymentsOfShortTermDebt
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:RepaymentsOfUnsecuredDebt
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument
us-gaap:ConsolidationItems, wec:TypesofOperatingRevenues
us-gaap:RevenueNotFromContractWithCustomer
us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues
wec:TypesofOperatingRevenues
wec:TypesofOperatingRevenues, wec:TypesofOtherOperatingRevenues
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
us-gaap:AwardType, us-gaap:SubsequentEventType
us-gaap:AwardType, us-gaap:SubsequentEventType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsShareBasedLiabilitiesPaid
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
us-gaap:AwardType, us-gaap:SubsequentEventType
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
us-gaap:AwardType, us-gaap:SubsequentEventType
us-gaap:ConsolidatedEntities, us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtWeightedAverageInterestRateOverTime
us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtType
us-gaap:ShorttermDebtAverageOutstandingAmount

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised
us-gaap:StatementEquityComponents

us-gaap:StockRepurchasedDuringPeriodValue
us-gaap:StatementEquityComponents

us-gaap:StockholdersEquityOther
us-gaap:StatementEquityComponents

us-gaap:TaxesExcludingIncomeAndExciseTaxes
us-gaap:ConsolidatedEntities, us-gaap:DerivativeInstrumentRisk
us-gaap:UnrealizedGainLossOnInterestRateCashFlowHedgesPretaxAccumulatedOtherComprehensiveIncomeLoss

wec:AmountsRecoverableFromCustomers
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:AnnualStandardForTheParticulateMatterNAAQS
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:Cashandrestrictedcashacquired

wec:EffectiveIncomeTaxReconciliationTaxExpenseBenefitUncertainTaxPosition

wec:EffectiveIncomeTaxReconciliationTaxExpenseBenefitUncertainTaxPositionPercentage

wec:EffectiveIncomeTaxReconciliationTaxexpensebenefitfederalexcessdeferredtaxamortizationWisconsinunprotected

wec:EffectiveIncomeTaxreconciliationFederalexcessdeferredtaxamortizationWIUnprotectedpercent

wec:EquityMethodInvestmentOther
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:FossilFueledGenerationCapacityToBeRetiredBy2025
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:PercentCarbonDioxideEmissionReductionFutureGoal
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:PercentCarbonDioxideEmissionReductionGoalBy2025
us-gaap:RegulatoryAgency, wec:RateCaseYear
wec:PercentageOfFirst15BasisPointsOfAdditionalEarningsRetainedByTheUtility
us-gaap:StatementBusinessSegments
wec:PercentageOfStorageNeedsProvidedByStorageFacility

wec:ReceivableInsuranceProceeds
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType
wec:RecoverablePlannedCapitalInvestment
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
wec:RelatedPartyTransactionChargesToRelatedParty
us-gaap:RegulatoryAgency, wec:RateCaseYear
wec:Returnonequityinexcessofauthorizedamountasapercent
dei:LegalEntity, us-gaap:PublicUtilitiesRegulatoryProceeding, us-gaap:RegulatoryAgency, wec:RateCaseYear
wec:SecuritizedRegulatoryAsset
us-gaap:ConsolidatedEntities
us-gaap:AwardType, us-gaap:SubsequentEventType
wec:Taxbenefitfromawardsotherthanoptions

wec:Taxrepairsamount

wec:Taxrepairspercentage

dei:EntityCommonStockSharesOutstanding
us-gaap:ConsolidatedEntities
us-gaap:AccountsPayableRelatedPartiesCurrent
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:AccountsReceivableGross
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:AccountsReceivableNet
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:ConsolidatedEntities
us-gaap:AccountsReceivableRelatedPartiesCurrent
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
us-gaap:AccrualForEnvironmentalLossContingencies

us-gaap:AccruedEnvironmentalLossContingenciesNoncurrent
us-gaap:RegulatoryAsset

us-gaap:AllowanceForDoubtfulAccountsReceivable
us-gaap:ConcentrationRiskByType
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AmountOfRestrictedNetAssetsForConsolidatedAndUnconsolidatedSubsidiaries

us-gaap:AssetRetirementObligation
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationAcquisitionOfLessThan100PercentNoncontrollingInterestFairValue
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationContingentConsiderationLiabilityNoncurrent
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities
dei:LegalEntity, us-gaap:BusinessAcquisition
us-gaap:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment
us-gaap:ConsolidatedEntities
us-gaap:CommercialPaper
us-gaap:ShortTermDebtType

us-gaap:DebtInstrumentCarryingAmount
us-gaap:ConsolidatedEntities
us-gaap:DebtInstrumentFaceAmount

us-gaap:DebtInstrumentUnamortizedDiscountPremiumNet

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredRevenueNoncurrent

us-gaap:DeferredTaxAssetsDeferredIncome

us-gaap:DeferredTaxAssetsGross
us-gaap:IncomeTaxAuthority
us-gaap:DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal
us-gaap:IncomeTaxAuthority
us-gaap:DeferredTaxAssetsTaxCreditCarryforwardsOther

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment
us-gaap:PublicUtility
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAmountsRecognizedInBalanceSheet
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
us-gaap:RetirementPlanType, wec:WeightedaverageAssumptions
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:RetirementPlanType, wec:WeightedaverageAssumptions
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
us-gaap:RetirementPlanType, wec:WeightedaverageAssumptions
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationWeightedAverageInterestCreditingRate
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsRemainderOfFiscalYear
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan
us-gaap:RetirementPlanType, wec:AgeCriteriaForMedicalBenefits, wec:WeightedaverageAssumptions
us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsPlanAssets
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
dei:LegalEntity, us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanPlanAssetsTargetAllocationPercentage
dei:LegalEntity, us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType, wec:Trusts
us-gaap:RetirementPlanType, wec:AgeCriteriaForMedicalBenefits, wec:WeightedaverageAssumptions
us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1

us-gaap:DerivativeAssetCollateralObligationToReturnCashOffset

us-gaap:DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset

us-gaap:DerivativeAssets

us-gaap:DerivativeCollateralObligationToReturnCash

us-gaap:DerivativeCollateralRightToReclaimCash
us-gaap:ConsolidatedEntities, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeFixedInterestRate

us-gaap:DerivativeInstrumentsAndHedges
us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeInstrumentsAndHedgesLiabilitiesNoncurrent
us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeInstrumentsAndHedgesNoncurrent
us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeLiabilities

us-gaap:DerivativeLiabilityCollateralRightToReclaimCashOffset

us-gaap:DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset

us-gaap:DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:EmployeeRelatedLiabilitiesCurrent
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions
us-gaap:AwardType
us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions

us-gaap:EnergyRelatedInventory

us-gaap:EnergyRelatedInventoryNaturalGasInStorage

us-gaap:EnergyRelatedInventoryOtherFossilFuel
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:EquityMethodInvestmentOwnershipPercentage
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName, us-gaap:StatementBusinessSegments

us-gaap:EquityMethodInvestments
us-gaap:ConsolidatedEntities
us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:EquitySecuritiesFvNiRestricted
us-gaap:FairValueByMeasurementFrequency

us-gaap:ExcessOfReplacementOrCurrentCostsOverStatedLIFOValue
dei:LegalEntity

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs

us-gaap:FinanceLeaseLiability
us-gaap:CounterpartyName
us-gaap:FairValueByMeasurementBasis

us-gaap:FinanceLeaseLiabilityCurrent
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityNoncurrent
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDue
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueAfterYearFive
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo
us-gaap:CounterpartyName

us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount
us-gaap:CounterpartyName

us-gaap:FinanceLeaseWeightedAverageDiscountRatePercent
us-gaap:CounterpartyName
dei:LegalEntity
us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
dei:LegalEntity, us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:IncomeStatementLocation
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths
us-gaap:IncomeStatementLocation
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFive
us-gaap:IncomeStatementLocation
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearFour
us-gaap:IncomeStatementLocation
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearThree
us-gaap:IncomeStatementLocation
us-gaap:FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo
dei:LegalEntity
us-gaap:FiniteLivedIntangibleAssetsGross
dei:LegalEntity, us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsCurrentCarryingValue

us-gaap:GuaranteeObligationsMaximumExposure
dei:LegalEntity, us-gaap:GuaranteeObligationsByNature
us-gaap:GuaranteeObligationsByNature

us-gaap:HostingArrangementServiceContractImplementationCostCapitalizedAfterAccumulatedAmortization
dei:LegalEntity, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:InsuranceSettlementsReceivableCurrent
us-gaap:PropertyPlantAndEquipmentByType
us-gaap:ConsolidatedEntities, us-gaap:DerivativeInstrumentRisk
us-gaap:InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet

us-gaap:InventoryRawMaterialsAndSuppliesNetOfReserves
dei:LegalEntity, us-gaap:JointlyOwnedUtilityPlant
us-gaap:JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService
dei:LegalEntity, us-gaap:JointlyOwnedUtilityPlant
us-gaap:JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress
dei:LegalEntity, us-gaap:JointlyOwnedUtilityPlant
us-gaap:JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation
dei:LegalEntity, us-gaap:JointlyOwnedUtilityPlant
us-gaap:JointlyOwnedUtilityPlantProportionateOwnershipShare

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LettersOfCreditOutstandingAmount

us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity

us-gaap:LineOfCreditFacilityRemainingBorrowingCapacity

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive
us-gaap:ConsolidatedEntities

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
us-gaap:ConsolidatedEntities

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
us-gaap:ConsolidatedEntities

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
dei:LegalEntity
us-gaap:LongtermDebtWeightedAverageInterestRate
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:LossContingencyAccrualAtCarryingValue
us-gaap:Ownership, us-gaap:StatementBusinessSegments
us-gaap:MinorityInterestOwnershipPercentageByParent
us-gaap:ConsolidatedEntities
us-gaap:NotesPayableRelatedPartiesClassifiedCurrent
us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransactionsByRelatedParty
us-gaap:ConsolidatedEntities
us-gaap:NotesReceivableRelatedPartiesCurrent
us-gaap:ConsolidatedEntities, us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards
us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwardsValuationAllowance

us-gaap:OtherMinorityInterests
us-gaap:ConsolidatedEntities, us-gaap:ShortTermDebtType
us-gaap:OtherShortTermBorrowings
us-gaap:ShortTermDebtType

us-gaap:PercentageOfLIFOInventory

us-gaap:PreferredStockValue
us-gaap:FairValueByMeasurementBasis

us-gaap:PrepaidExpenseCurrent
us-gaap:ConsolidatedEntities
us-gaap:PrepaidTaxes
us-gaap:CounterpartyName
us-gaap:PropertyPlantAndEquipmentOther
us-gaap:CounterpartyName
us-gaap:PropertyPlantAndEquipmentOtherAccumulatedDepreciation

us-gaap:PropertyPlantAndEquipmentOtherNet
us-gaap:CounterpartyName

us-gaap:PublicUtilitiesAmountOfAllowanceForEarningsOnEquityCapitalizedForRateMakingPurposes
dei:LegalEntity, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PublicUtilitiesPropertyPlantAndEquipmentNet

us-gaap:PurchaseObligation
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueAfterFifthYear
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueInFifthYear
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueInFourthYear
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueInNextTwelveMonths
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueInSecondYear
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:PurchaseObligationDueInThirdYear
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:SupplyCommitment
us-gaap:ProductOrService, us-gaap:SupplyCommitment

us-gaap:RegulatoryAssets
us-gaap:JointlyOwnedUtilityPlant
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:RegulatoryAsset
us-gaap:PublicUtility
us-gaap:PublicUtility, us-gaap:RegulatoryAsset
us-gaap:RegulatoryAgency, us-gaap:RegulatoryAsset
us-gaap:RegulatoryAsset

us-gaap:RegulatoryAssetsCurrent
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:RegulatoryAsset
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:RegulatoryAsset, us-gaap:SubsequentEventType

us-gaap:RegulatoryAssetsNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:RegulatoryLiabilities
us-gaap:RegulatoryLiability

us-gaap:RegulatoryLiabilityCurrent

us-gaap:RegulatoryLiabilityNoncurrent
us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName
us-gaap:RelatedPartyTransactionDueFromToRelatedParty

us-gaap:RemainingAmountsOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided

us-gaap:RestrictedCashCurrent
us-gaap:ConsolidatedEntities

us-gaap:RestrictedCashNoncurrent
us-gaap:ConsolidatedEntities

us-gaap:RestructuringReserve

us-gaap:RetainedEarningsUndistributedEarningsFromEquityMethodInvestees
dei:LegalEntity
us-gaap:SecuredDebt
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:SecuredDebtCurrent
dei:LegalEntity
us-gaap:SeniorNotes
us-gaap:ConsolidatedEntities
us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:SeniorNotesCurrent
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
us-gaap:AwardType
us-gaap:SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1

us-gaap:ShortTermBorrowings
us-gaap:ConsolidatedEntities, us-gaap:ShortTermDebtType
us-gaap:ShortTermDebtWeightedAverageInterestRate
us-gaap:ShortTermDebtType
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:TradingSecurities
us-gaap:FairValueByMeasurementFrequency

us-gaap:UnamortizedDebtIssuanceExpense

us-gaap:UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
dei:LegalEntity
us-gaap:UnsecuredDebt
dei:LegalEntity, us-gaap:DebtInstrument
us-gaap:UnsecuredDebtCurrent

us-gaap:ValuationAllowancesAndReservesBalance

wec:AccountsReceivablePastDueGreaterthan90Days
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:Acquisitionpurchaseprice
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:AdditionalCapitalExpenditures
dei:LegalEntity, us-gaap:RegulatoryAgency
wec:AmountOfFundsProvidedThroughBillPaymentAssistanceProgram
dei:LegalEntity, us-gaap:RegulatoryAgency, us-gaap:SubsequentEventType

wec:Amountofnetaccountsreceivablewithregulatoryprotections

wec:BalanceofTaxBenefitCarryforward
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
wec:Bonusdepreciationpercentage
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:CapacityOfGenerationUnit
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:BusinessAcquisition
us-gaap:CounterpartyName
wec:CapacityOfSolarProjectOwnedByEntityInMegawatts

wec:CostsIncurredForRepairsAndRestorations
dei:LegalEntity, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentByType
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:CurrentProjectInvestment

wec:DeferredTaxAssetsFutureFederalTaxBenefitsNonCurrent

wec:DeferredTaxAssetsOtherNonCurrent

wec:DeferredTaxAssetsTaxGrossUpRegulatoryItemsNonCurrent

wec:DeferredTaxAssetsUncertaintyInIncomeTaxes

wec:DeferredTaxLiabilitiesEmployeeBenefitsAndCompensationNonCurrent

wec:DeferredTaxLiabilitiesInvestmentInTransmissionAffiliateNonCurrent

wec:DeferredTaxLiabilitiesOtherNonCurrent
us-gaap:PublicUtility
wec:DeferredUnprotectedTaxBenefits
us-gaap:RetirementPlanType
wec:DefinedBenefitPlanNetRegulatoryAssets
us-gaap:RetirementPlanType
wec:DefinedBenefitPlanNetRegulatoryAssetsNetActuarialGainsLosses
us-gaap:RetirementPlanType
wec:DefinedBenefitPlanNetRegulatoryAssetsPriorServiceCostCredit
dei:LegalEntity, us-gaap:RegulatoryAgency
wec:DepreciationAndInterestExpenseApprovedForDeferral

wec:DerivativeInstrumentsAndHedgesLiabilitiesGrossCurrent
us-gaap:DerivativeInstrumentRisk
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:StatutoryAccountingPracticesByJurisdiction
wec:EnergyOptimizationTarget
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:EnvironmentalCapitalAndOperatingCosts
us-gaap:RelatedPartyTransactionsByRelatedParty
wec:FirmCapacityFromFinanceLeasePowerPurchaserAgreement

wec:GuaranteeObligationsMaximumExposureExpireLessThanOneYear
us-gaap:GuaranteeObligationsByNature

wec:GuaranteeObligationsMaximumExposureExpireOverThreeYears
us-gaap:GuaranteeObligationsByNature

wec:GuaranteeObligationsMaximumExposureExpireWithinOneToThreeYears
us-gaap:GuaranteeObligationsByNature

wec:IntegrysFairValueAdjustmentLongTermDebt
dei:LegalEntity, us-gaap:JointlyOwnedUtilityPlant
wec:JointlyOwnedUtilityPlantProportionateOwnershipShareOfCapacity
us-gaap:CounterpartyName
wec:MaximumRegulatoryAssetForFinanceLeasePowerPurchaseContract
us-gaap:AwardType
wec:MinimumExercisePriceofStockOptionasaPercentofCommonStockFairValueontheGrantDate
dei:LegalEntity
wec:NaturalGasPriceBenchmark
us-gaap:PublicUtility
wec:NetBookValueOfRetiredPlant
us-gaap:ProductOrService
wec:NumberOfCustomers
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:OwnershipInterestOfGeneratingFacilityAcquired
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:Ownershipinterestofwindgeneratingfacilityacquired
dei:LegalEntity, us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:PerMileRateofMethaneEmissionReduction
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:StatutoryAccountingPracticesByJurisdiction
wec:PercentGoalElectricityConsumptionRenewables
dei:LegalEntity, us-gaap:BusinessAcquisition
wec:PercentageOfTaxBenefitsEntitledTo
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:StatutoryAccountingPracticesByJurisdiction
wec:PercentageRenewablePortfolioRequirement2019Through2020
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:StatutoryAccountingPracticesByJurisdiction
wec:PercentageRenewablePortfolioRequirement2021
dei:LegalEntity, us-gaap:Range, us-gaap:StatementClassOfStock, wec:Restrictions
wec:Percentageofnetincomeforwhichdividendscanbedeclared

wec:Percentofaccountsreceivablepastduegreaterthan90dayswithregulatorymechanismstocollect
us-gaap:ProductOrService
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

wec:Percentofnetaccountsreceivablewithregulatoryprotections
us-gaap:BusinessAcquisition
wec:Percentoftaxbenefitsentitledto
us-gaap:PropertyPlantAndEquipmentByType, us-gaap:PublicUtilityRegulatedOrUnregulatedStatus
wec:PropertyPlantAndEquipmentGrossExcludingConstructionWorkInProgress
us-gaap:PublicUtilityRegulatedOrUnregulatedStatus, us-gaap:StatementBusinessSegments
us-gaap:PublicUtilityRegulatedOrUnregulatedStatus
wec:PropertyPlantAndEquipmentNetExcludingConstructionWorkInProgress

wec:ReceivableRecordedForFutureInsuranceRecoveries
us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency
wec:RegulatoryAssetRecoveryOfRemediationExpenditures

wec:RemainingAmountsOfRegulatoryAssetsEarningLongTermInterestRateReturnOnInvestment

wec:RemainingAmountsOfRegulatoryAssetsEarningShortTermInterestRateReturnOnInvestment
dei:LegalEntity, us-gaap:ProductOrService, us-gaap:LossContingenciesByNatureOfContingency, us-gaap:StatutoryAccountingPracticesByJurisdiction
wec:RenewableEnergyPercent
us-gaap:CounterpartyName
wec:Solarlandleaseacreage

wec:TotalCommonShareholdersEquity

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Other Nonoperating Income Expense
Balance Sheet
Operating Lease Right Of Use Asset
Assets
Operating Lease Right Of Use Asset
Current Assets
Cash And Cash Equivalents At Carrying Value
NonCurrent Assets
Operating Lease Right Of Use Asset
PropertyPlantAndEquipmentNet
Accumulated Depreciation Depletion And Amortization Property Plant And Equipment
Liabilities
Derivative Liabilities
Current Liabilities
Employee Related Liabilities Current
Noncurrent Liabilities
Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
Per Share
Common Stock Dividends Per Share Declared
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Increase Decrease In Accounts Payable
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Weighted Average Number Of Shares Outstanding Basic
DividendsAndRepurchase
Payments For Repurchase Of Common Stock
NonoperatingIncomeExpense
Nonoperating Income Expense
LesseeOperatingLeaseLiabilityPaymentsDue
Lessee Operating Lease Liability Payments Due Year Four
AccountsReceivable
Allowance For Doubtful Accounts Receivable Current

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:CommonStockValue ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█▅▅▅▅▅▅▄▄▄▄▄▄3.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.28456.74510.64419.74398.34367.14322.04233.04198.14195.44203.64135.14147.24081.1
us-gaap:CommonStockSharesOutstanding 315.434531NA315.434531NA315.434531315.434531315.434531315.435595315.43582315.438398315.523192315.526051315.533448315.538808315.574624315.575562315.576571315.579222315.614941315.617299315.619968315.647207315.683496315.684451NANA225.517339NANANA225.962959NANANA229.039456NANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁316.3316.2NA316.5316.5316.7NA316.8316.7316.7NA316.9316.9316.9NA317.5317.4317.2NA316.9317.0317.1NA317.1229.1227.3NA227.4227.6227.7NA228.8230.5231.2NA232.9233.1
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ▄▄315.4315.4NA315.4315.4315.4NA315.4315.4315.5NA315.5315.5315.5NA315.6315.6315.6NA315.6315.6315.7NA315.7227.5225.5NA225.5225.5225.8NA226.8228.4228.9NA230.4230.4
us-gaap:EarningsPerShareBasic NANA0.760.850.771.430.770.740.751.330.650.740.731.241.370.680.631.130.620.690.571.10.570.580.360.870.540.560.590.92NANANANA0.430000000000000160.680.52
us-gaap:EarningsPerShareDiluted NANA0.760.840.761.430.770.740.741.330.650.740.731.231.360.680.631.120.610.680.571.090.570.580.350.860.530.560.580.91NANANANA0.430000000000000160.670.51
us-gaap:IncomeLossFromContinuingOperationsPerBasicShare ▁█8.8e-071.6200000000000002e-06NA8.5e-077.7e-071.4299999999999999e-06NA7.4e-077.5e-071.33e-06NA7.4e-077.3e-071.24e-06NA6.800000000000001e-076.3e-071.13e-06NA6.9e-075.699999999999999e-071.1e-06NA5.8e-073.6e-078.7e-07NA5.6e-075.9e-079.200000000000001e-076.400000000000001e-076.1e-075.2e-077.7e-074.3000000000000017e-076.800000000000001e-075.2e-07
us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare ▁█8.7e-071.61e-06NA8.4e-077.6e-071.4299999999999999e-06NA7.4e-077.4e-071.33e-06NA7.4e-077.3e-071.23e-06NA6.800000000000001e-076.3e-071.12e-06NA6.800000000000001e-075.699999999999999e-071.0900000000000002e-06NA5.8e-073.5e-078.6e-07NA5.6e-075.8e-079.100000000000001e-076.299999999999999e-076e-075.2e-077.6e-074.3000000000000017e-076.7e-075.1e-07
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
 Cost Ratio us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate▃▄▂▄█▄▇▃▂▁185.9188.7180.4187.8203.1186.8199.6184.9182.2177.7NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Net profit Margin us-gaap:StatementBusinessSegments us-gaap:CorporateAndOther▄▄0.10.1NANA0.90.5NANANANANANANANANANANANANANANANANANA0.50.30.40.30.30.30.30.40.30.30.30.30.3
 Net profit Margin us-gaap:StatementBusinessSegments wec:NonUtilityEnergyInfrastructure▁█133.5137.6NANA125.3129.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Operating Margin us-gaap:StatementBusinessSegments wec:NonUtilityEnergyInfrastructureNANANA123.5125.3129.6125.4119.4123.3127.8118.1115.2117.0118.112.813.6NANA6.26.2NANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
 TTM Greenblatt ROC _ _▄█▄▄▄█▄▃▃▇▃▃▃▇▅▄▄█▄▅▄▇▄▄▁▄▂▂▂▄▃▂▂▃▂▃▂368.8629.3370.5370.2338.8626.6363.1310.9314.6542.8289.8302.7330.8545.1412.1393.6362.2617.3361.7399.0332.1589.3380.2345.7165.8358.8243.5246.1240.7381.8271.6258.0229.5321.0201.4280.6222.6
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:ComprehensiveIncomeNetOfTax ▄█▃▄▃▇▄▃▃▆▃▃▃▆▇▃▃▅▃▃▂▅▂▃▁▃▁▂▂277.1511.2238.6267.7241.4449.5246.9233.8233.1418.7200.0233.1228.9391.8433.1215.3198.9356.4193.6216.3181.5345.9172.7182.192.2195.8121.4126.3133.0NANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest ▁█-0.6-0.1NANA0.2-0.20.0-0.3-0.20.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest ▄█▃▄▃▇▄▃▃▆▃▃▃▆▇▃▃▅▃▃▂▅▂▃▁▃276.8511.4239.2268.0241.9449.6247.2233.8233.2419.0200.3233.4229.2392.1433.4215.6199.2356.7193.9216.6181.8346.2173.3182.792.5196.1NANANANANANANANANANANA
us-gaap:CostOfGoodsAndServicesSold ▂█▃▂▂▄▄▂▂▆▅▂▂▆▄▂▂▆▄▃▂▅▄▃▁▃▂▁525.91265.6657.5482.8444.5734.7693.0484.3491.91009.6854.0524.1547.7972.1797.2542.7541.8941.1745.5554.7508.3838.9682.6590.6353.0613.9523.5407.4NANANANANANANANANA
us-gaap:CostsAndExpenses ▂█▄▂▁▃▄▂▂▆▆▂▂1307.42062.11562.91280.81209.91482.01584.41297.11275.61834.61787.01341.01341.7NANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:GainsLossesOnExtinguishmentOfDebt NANA-10.5NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:SubsequentEventType us-gaap:SubsequentEventNANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▄█▃▄▃▇▃▃▃▆▂▃▃▆▄▄▄█▄▄▃█▄▃▁▄▂▂▂▄▂▂▂▃329.8585.2276.8314.0295.9542.6277.7245.6251.0485.4218.7250.5282.4478.7357.6345.4315.2570.2306.1345.7295.3559.6318.8293.0144.1318.2199.4206.6207.3337.9232.0218.2189.3277.0NA245.8185.9
us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest NANANA267.1242.1452.6NA234.3235.8420.4NA233.5231.3390.4NA215.7NANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeTaxExpenseBenefit ▄▅▄▄▄▅▄▃▃▄▃▃▄▅▁▆▆█▆▆▆█▆▆▄▆▅▅▅▆▅▅▅▅▄▅▄54.174.937.246.953.890.033.511.315.265.013.417.051.188.3-75.3129.7115.8213.3111.4128.4113.6213.1137.7110.563.2122.476.880.374.3130.386.580.770.3100.453.789.766.6
us-gaap:IncomeTaxesPaidNet ▂▄█▁▄▅▅▄▅▄▁▅▇▄▄▄▄▃▂▄▃▄▄▄▄▄▄▄▄▅-30.72.555.5-37.6-1.211.29.50.314.90.2-39.68.347.9-0.32.12.2-0.6-8.9-28.0-4.3-7.80.47.3-1.0-1.34.30.04.47.610.0NANANA2.0NANANA
us-gaap:InterestExpense ▇▇▇▇████▇█▇▆▆▆▆▅▅▆▅▅▅▅▆▅▁▁▁▁▁▁▁▁▁▂▂▁▁120.0119.5117.9122.0124.4129.4127.2125.8124.1124.4117.9112.0108.5106.7105.3103.8101.9104.7102.699.1100.1100.9105.8103.862.159.759.860.459.062.361.862.063.365.066.960.961.5
us-gaap:InterestPaidNet ▇▃▇▄▇▄▇▃█▃▇▃▇▃▇▂▇▃▇▂▇▂█▂▄▁▄▁▅▁▅▁▅▁▅▁▄163.176.8160.580.0166.685.8168.070.0181.666.3163.462.5147.168.5155.548.9152.756.6151.251.5168.540.7178.634.196.620.397.721.0101.221.2103.818.7106.221.7103.319.991.5
 us-gaap:NetIncomeLoss us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate▃▃▃▄█▂█▂▁▁65.465.164.866.780.263.180.3999999999999861.560.058.5NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLossAttributableToNoncontrollingInterest ▁█-0.6-0.1NANA0.2-0.20.0-0.3-0.20.00.00.00.0NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLossAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterest▁█-0.6-0.1NANA0.2-0.2NA-0.3-0.2NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic ▄█▄▄▄▇▄▄▄▇▃▃▃▆▇▃▃▅▃▃▃▅▃▃▁▃▂▂▂▃276.0510.1239.0266.8241.6452.5243.9234.3235.7420.1205.0233.2231.0390.1432.6215.4199.1356.6194.4217.0181.4346.2179.3182.580.9195.8121.4126.3133.0207.6NANANANANANANA
us-gaap:NonoperatingIncomeExpense ▆▆▁▅▆▂▂▄▄▅▃▅▅▄▅▅▆▆▅▅▇▇▄▅█▆▆▆-39.0-44.1-93.7-56.2-42.9-84.0-85.4-65.3-63.6-57.4-71.1-52.2-48.4-66.4-54.5-48.2-47.0-47.1-55.6-53.3-36.8-29.7-61.4-52.7-21.4-40.3-44.1-39.5NANANANANANANANANA
 us-gaap:NonoperatingIncomeExpense us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate▂▁▁▂▆▁█▁▁▁-28.1-28.5-28.8-28.1-25.4-28.5-24.4-28.7-28.6-28.8NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingIncomeLoss ▄█▄▄▄█▄▃▃▇▃▃▃▇▅▄▄█▄▅▄▇▄▄▁▄▂▂▂▄▃▂▂▃▂▃▂368.8629.3370.5370.2338.8626.6363.1310.9314.6542.8289.8302.7330.8545.1412.1393.6362.2617.3361.7399.0332.1589.3380.2345.7165.8358.8243.5246.1240.7381.8271.6258.0229.5321.0201.4280.6222.6
us-gaap:OtherComprehensiveIncomeLossNetOfTax ▄▄▃▄▄▂▅▃▃▃▂▄▃▄▄▄▄▄▃▃▄▃▁▃█▄▄▄▄1.11.1-0.40.9-0.2-3.03.0-0.5-2.6-1.4-5.0-0.1-2.11.70.5-0.1-0.2-0.2-0.8-0.70.1-0.3-6.6-0.411.30.00.00.00.0NANANANA0.0NA0.00.0
us-gaap:OtherNonoperatingIncomeExpense █▇▄▅▆▂▅▅▅▆▂▆▆▂▄▄▃▄▂▂▇▇▄▃▆▁▁▁▂▁▁▂▂▂▁▂▂39.732.819.625.728.65.625.921.823.630.95.326.131.47.519.416.413.115.78.27.532.432.718.711.126.13.01.32.98.11.13.55.15.84.41.29.08.6
us-gaap:ProfitLoss ▃█▂▂▂▇▂▂▂▆▁275.7510.3239.6267.1242.1452.6244.2234.3235.8420.4206.2NANANA433.8NANANANANANANANANA80.9195.8121.4126.3133.0207.6144.3137.5119.0176.698.8156.1119.3
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:CommercialandIndustrialCustomer,us-gaap:NaturalGasUsRegulated,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▃▇▄▁▂▆▄▁▂█▅▁▂▇51.5102.764.528.636.591.471.129.345.1116.280.829.447.3109.4NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:CommercialandIndustrialCustomer,us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂▅▄▁▂▆▅▁▂█▅▁▂▇17.343.937.310.216.651.744.711.520.572.044.012.618.764.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:CommercialandIndustrialCustomer,us-gaap:NaturalGasUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▁█159.0323.0NA67.1100.1294.4NA70.8121.4387.9NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:CommercialandIndustrialCustomer,us-gaap:NaturalGasUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▇▄▁▂▆▅▁▂█▆▁▂█90.2176.4111.528.347.0151.3134.430.055.8199.7150.335.063.5187.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:DowntownMilwaukeeSteamCustomers,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▁▂▄▃▁▂▅▄▁▂▅4.214.86.32.54.18.46.52.44.310.17.22.74.59.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Largecommercialandindustrialcustomers,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▅▃▂▇▁▂▃▇▄▄▄█▇▃224.5209.5195.1244.0187.8194.6203.9237.9217.8212.3217.0249.7241.6203.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Otherretailcustomer,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▁▇█▁▁▄▆▁▄▇▅▅▃▇6.97.87.96.96.97.37.66.97.37.87.57.57.27.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Otherutility,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▃▁▃▃▅▅█▆▂▇▂▁▂6.05.41.44.95.38.58.815.310.52.513.72.20.42.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Otherutility,us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▃█▃▃▃▁▂▃▂▁▃▃▃▁5.182.83.08.8-1.2-17.7-5.94.2-2.1-23.14.68.35.5-25.1NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:ResaleCustomers,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▃▆▁▂▂▄▄▂▅▃▅▃▁█37.462.723.133.728.445.243.429.549.440.852.640.725.173.8NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Residentialcustomer,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▄▄█▄▃▃▆▁▃▃▆▃▂419.0423.7419.5500.8418.7404.9390.5454.7356.7406.7393.0465.3393.7384.3NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Residentialcustomer,us-gaap:NaturalGasUsRegulated,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▇▄▁▂▆▄▁▂█▆▁▂▇199.1333.9233.3128.6157.4282.9232.1117.6154.1354.0268.5112.7163.7332.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Residentialcustomer,us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂▆▄▁▂▆▄▁▂█▅▁▂█37.987.966.718.840.095.371.222.539.3125.282.120.137.9123.2NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Residentialcustomer,us-gaap:NaturalGasUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▁█425.6769.4NA222.0323.2691.3NA209.4319.6863.1NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Residentialcustomer,us-gaap:NaturalGasUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▇▅▁▂▆▅▁▂█▆▁▂▇188.6347.6239.174.6125.8313.1258.569.3126.2383.9277.871.9128.1356.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Smallcommercialandindustrial,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▃▂▇▁▂▃█▃▃▄█▅▃346.6331.4321.6373.6307.1323.6333.8385.6331.3333.9336.4388.2353.3330.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:TotalRetailCustomers,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▃▂█▁▂▂▇▁▃▂█▄▁997.0972.4944.11125.3920.5930.4935.81085.1913.1960.7953.91110.7995.8926.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:TotalRetailCustomers,us-gaap:NaturalGasUsRegulated,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▃▇▄▁▂▆▄▁▂█▅▁▂▇250.6436.6297.8157.2193.9374.3303.2146.9199.2470.2349.3142.1211.0442.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:TotalRetailCustomers,us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂▅▄▁▂▆▅▁▂█▅▁▂█55.2131.8104.029.056.6147.0115.934.059.8197.2126.132.756.6187.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:TotalRetailCustomers,us-gaap:NaturalGasUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▁█584.61092.4NA289.1423.3985.7NA280.2441.01251.0NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:TotalRetailCustomers,us-gaap:NaturalGasUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▇▅▁▂▆▅▁▂█▆▁▂▇278.8524.0350.6102.9172.8464.4392.999.3182.0583.6428.1106.9191.6544.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Transportationcustomers,us-gaap:NaturalGasUsRegulated,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂▆▃▁▂▆▅▂▂█▅▁▃▇48.874.256.640.046.372.767.044.346.887.268.543.354.677.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Transportationcustomers,us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▃█▅▁▃▇▅▂▃█▇▁▃▇6.611.08.75.37.010.58.65.66.311.110.24.96.89.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Transportationcustomers,us-gaap:NaturalGasUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▁█73.2109.6NA61.070.3107.3NA64.369.3120.2NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Transportationcustomers,us-gaap:NaturalGasUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄█▇▂▃█▅▁▃▆▅▁▃▆17.824.422.315.717.024.120.114.416.221.919.513.916.421.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers,us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Wholesalecustomer,us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂▂▃▄▃▃▃▆▄▄▁█▇▆38.639.744.146.541.342.144.153.144.647.734.862.058.454.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:ElectricityUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▄▂█▁▂▂▇▂▃▃█▄▃1083.21095.01019.00000000000051212.9999.61034.61038.61185.41021.91061.81062.21218.31084.21067.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:ElectricityUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▄▄▂█▁▂▂▇▂▃▃█▄▃1083.21095.01019.00000000000051212.9999.61034.61038.61185.41021.91061.81062.21218.31084.21067.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▁▂▄▃▁▂▆▄▁▂▅266.1693.5366.4213.4254.5433.6365.0190.0232.8544.6432.3193.2273.8507.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▅▄▁▂▆▅▁▂▆66.9225.6115.743.162.4139.8118.643.864.0185.2140.945.968.9172.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▅▄▁▂▆▅▁▂▆545.71546.4860.5407.0524.71032.3864.4384.9524.11294.71002.0406.5579.11198.3NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▆▄▁▂▇▅▁▂▆212.7627.3378.4150.5207.8458.9380.8151.1227.3564.9428.8167.4236.4518.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▁▂▄▃▁▂▆▄▁▂▅266.1693.5366.4213.4254.5433.6365.0190.0232.8544.6432.3193.2273.8507.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▅▄▁▂▆▅▁▂▆66.9225.6115.743.162.4139.8118.643.864.0185.2140.945.968.9172.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▂▁▄▃▁▁▆▄▂▂▆1628.92641.41879.51619.91524.32066.91903.01570.31546.02356.52064.21624.81663.32266.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▃▁▅▄▃▂▇▅▃▃▆1295.91722.31397.41363.41207.41493.51419.41336.51249.21626.71491.01385.71320.61585.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomerNANANA0.10.00.00.00.00.00.10.00.10.10.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▅█▄▄▄▅▃▄▄▃▄▂▁▁4.44.74.34.24.24.44.14.24.24.14.34.03.93.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▅█▄▄▄▅▃▄▄▄▄▃▂▁4.44.74.24.34.24.44.14.24.24.24.34.14.03.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,srt:ConsolidationEliminations,us-gaap:RevenueFromContractWithCustomerNANANA-8.3-8.2-14.1NA-8.4-9.1-14.7NA-12.7-12.7NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,wec:NonUtilityEnergyInfrastructure,us-gaap:RevenueFromContractWithCustomer▂▆▄▁▁▆▄▁▂█▃▂▂▇9.414.612.1000000000000039.18.714.512.38.99.816.410.510.010.014.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,srt:ConsolidationEliminations,us-gaap:RevenueFromContractWithCustomerNANANA-8.3-8.2-14.1NA-8.4-9.1-14.7NA-12.7-12.7NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,wec:NonUtilityEnergyInfrastructure,us-gaap:RevenueFromContractWithCustomer▂▆▄▁▁▆▄▁▂█▃▂▂▇9.414.612.1000000000000039.18.714.512.38.99.816.410.510.010.014.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,srt:ConsolidationEliminations,us-gaap:RevenueFromContractWithCustomerNANANA-1.6-3.9-1.6NA-0.7-3.1-0.7NA-0.7-3.1NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,us-gaap:CorporateAndOther,us-gaap:RevenueFromContractWithCustomerNANA0.00.50.80.40.41.30.81.51.52.32.81.3NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:NonUtilityEnergyInfrastructure,us-gaap:RevenueFromContractWithCustomer██▆▄▅▅▄▃▄▄▂▁▂▁24.223.218.3999999999999914.717.116.414.612.015.313.310.37.99.37.1NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofNonUtilityOperatingRevenues,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,us-gaap:TransferredOverTime,naics:ZZ811412,us-gaap:RevenueFromContractWithCustomer▅█▄▄▄▅▃▄▄▃▃▂▁▁4.44.74.34.24.24.44.14.24.24.14.14.03.93.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofNonUtilityOperatingRevenues,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,us-gaap:TransferredOverTime,us-gaap:AlternativeEnergy,us-gaap:RevenueFromContractWithCustomer▇█▅▃▃▄▂▁▂▂14.515.810.67.47.39.37.04.95.96.2NANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofNonUtilityOperatingRevenues,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:Distributedrenewablesolarprojectrevenues,us-gaap:RevenueFromContractWithCustomerNANA0.00.30.70.40.41.30.81.51.62.32.81.3NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofNonUtilityOperatingRevenues,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:Other,us-gaap:RevenueFromContractWithCustomerNANA-0.10.20.20.00.10.00.00.10.00.10.10.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofNonUtilityOperatingRevenues,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,wec:WePowerrevenues,us-gaap:RevenueFromContractWithCustomer▃▃▃▃▃▁▇█▇█▇█▆█5.85.85.85.85.85.56.36.46.36.46.36.46.26.4NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofOperatingRevenues us-gaap:ElectricityUsRegulated,us-gaap:RevenueFromContractWithCustomer▄▄▂█▁▂▂▇▂▃▃█▄▃1083.21095.01019.00000000000051212.9999.61034.61038.61185.41021.91061.81062.21218.31084.21067.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofOperatingRevenues us-gaap:NaturalGasUsRegulated,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▅▄▁▂▆▅▁▂▆546.41547.7861.2407.8525.21032.7864.8385.4524.81296.41004.0403.8576.41210.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofOperatingRevenues us-gaap:PublicUtilities,us-gaap:RevenueFromContractWithCustomer▂█▃▂▁▄▃▁▁▆▄▂▂▆1629.62642.71880.21620.71524.82067.31903.41570.81546.72358.22066.21622.11660.62278.4NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,wec:TypesofOperatingRevenues wec:Othernonutilityrevenues,us-gaap:RevenueFromContractWithCustomer▇█▅▄▄▅▄▃▄▄▃▂▂▁24.726.320.617.918.219.617.916.817.218.314.813.613.011.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Illinois,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▁▂▄▃▁▂▆▄▁▂▅266.1693.5366.3213.5254.5433.6365.0190.0232.8544.7432.3193.3273.9507.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:OtherStates,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▁▂▅▄▁▂▆▅▁▂▆71.3230.3119.9999999999999747.366.6144.2122.748.068.2189.3145.249.972.8176.6NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:PublicUtility,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▃▂▁▄▃▁▁▆▄▂▂▆1633.32646.11883.71624.21528.52071.31907.11574.51550.22360.72068.51628.91667.32269.9NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,us-gaap:TimingOfTransferOfGoodOrService,wec:TypesofOperatingRevenues wec:Wisconsin,us-gaap:TransferredOverTime,us-gaap:RevenueFromContractWithCustomer▂█▄▃▁▅▄▃▂▇▅▃▃▆1295.91722.31397.41363.41207.41493.51419.41336.51249.21626.71491.01385.71320.61585.7NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues srt:ConsolidationEliminations,us-gaap:RevenueFromContractWithCustomerNANANA-9.9-12.1-15.7NA-9.1-12.2-15.4NA-13.4-15.8NANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues us-gaap:CorporateAndOther,us-gaap:RevenueFromContractWithCustomerNANA0.00.50.80.40.41.30.81.51.52.32.81.3NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments,wec:TypesofOperatingRevenues wec:NonUtilityEnergyInfrastructure,us-gaap:RevenueFromContractWithCustomer▇█▅▃▄▆▄▂▄▅▂▁▁▂33.637.830.523.825.830.926.920.925.129.720.817.919.322.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax wec:TypesofOperatingRevenues us-gaap:RevenueFromContractWithCustomer▂█▃▂▁▄▃▁▁▆▄▂▂▆1654.32669.01900.81638.61543.02086.91921.31587.61563.92376.52081.01635.71673.62290.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:Revenues ▄█▅▄▃▆▅▄▄▇▆▄▄▆▅▄▄▆▅▄▄▆▅▄▁▃▂▁▁▄▂▁▁▂▂▁▁1676.22691.41933.41651.01548.72108.61947.51608.01590.22377.42076.81643.71672.52286.52055.01657.51631.52304.51963.01712.51602.02194.81848.31698.7991.21387.91225.11033.31043.71695.01178.31053.21012.31275.21071.21039.3944.7
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:Assets ███▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▅▅▆▅▅▁▁▁▁▁▁▁▁▁▁▁▁37794.937600.637028.135422.035042.034832.234951.834377.233934.333737.133475.832562.431937.631785.631590.531013.030559.630016.630123.229443.529175.329104.629355.228769.628614.515135.615163.414724.914619.814800.814769.414372.814317.014295.314285.013834.713887.6
 us-gaap:Liabilities us-gaap:AwardType us-gaap:PerformanceSharesNANA45.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LiabilitiesAndStockholdersEquity ███▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▅▅▆▅▅▁▁▁▁▁▁▁▁▁▁▁▁37794.937600.637028.135422.035042.034832.234951.834377.233934.333737.133475.832562.431937.631785.631590.531013.030559.630016.630123.229443.529175.329104.629355.228769.628614.515135.615163.414724.914619.814800.814769.414372.814317.014295.314285.013834.713887.6
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 us-gaap:StockholdersEquity us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate█▇▆▅▄▁▁2317.52304.22292.12270.72258.12218.42214.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterestNANA162.4NANANA110.8NANANA23.4NANANA0.0NANANA0.0NANANA0.0NANANANANANANANANANANANANANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:ParentNANA10469.7NANANA10113.4NANANA9788.9NANANA9461.4NANANA8929.8NANANA8654.8NANANA4419.7NANANA4233.0NANANA4135.1NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:RetainedEarningsNANA6329.6NANANA5927.7NANANA5538.2NANANA5176.8NANANA4613.9NANANA4299.8NANANA4117.3NANANA3881.0NANANA3632.5NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents wec:TotalEquityNANA10662.5NANANA10254.6NANANA9842.7NANANA9491.8NANANA8960.2NANANA8685.2NANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:AssetsCurrent ██▆▅▄▅▇▅▅▆▇▅▅▆▇▅▅▅▇▅▅▅▇▇█▂▃▂▂▄▄▂▂▂▂▁▂2278.12355.52083.01727.21713.41845.32093.61773.01838.72008.32247.61839.71810.41980.82213.51823.31779.71855.32168.71817.71765.91896.42206.82181.92276.81326.41535.41274.51285.51545.01551.11238.21271.11313.81313.91084.81236.9
us-gaap:CashAndCashEquivalentsAtCarryingValue ▂▁▁▁▁▁▂▁▂▂▃▁▂▂▂▁▂▂▂▁▂▂▂▁█▃▃▄▂▂▁▁▁▁▂▁▁35.026.124.813.113.315.437.520.037.930.684.514.529.848.138.918.136.545.737.525.032.134.749.822.2214.465.261.988.733.427.626.018.521.024.735.613.013.1
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▅▄▃▂▃▃▄▃▄▄█▁▂▃▂▁▂▃▃99.789.672.661.262.465.782.366.690.789.1146.140.252.071.758.638.558.373.472.7NANANA168.8NANANA61.9NANANANANANANANANANA
us-gaap:AccountsReceivableNetCurrent ▅█▅▁▂▅▅1182.71369.91202.8911.8957.91176.91176.5NANANA1280.9NANANA1350.7NANANA1241.7NANANA1028.6NA667.5437.3352.1339.0404.9605.8406.0299.0327.3389.0285.3298.6297.3
us-gaap:OtherAssetsCurrent █▂▄▃▄▄▄▅▅▂▅▄▂▁▅▂▂▁▇▂▆▃▃110.440.563.459.464.261.968.081.880.350.377.261.849.334.074.943.047.339.397.549.589.159.558.8NANANA38.6NANANA12.9NANANA107.9NANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:AssetsNoncurrent ██▇▆▆▆▆▅▅▄▄▄▃▃▂▂▂▁▁35516.835245.134945.133694.833328.632986.932858.232604.232095.631728.831228.230722.730127.229804.829377.029189.728779.928161.327954.5NANANA27148.4NANANANANANANANANANANANANANA
 us-gaap:ConstructionInProgressGross us-gaap:PublicUtilityRegulatedOrUnregulatedStatus us-gaap:RegulatedOperationNANA683.9NANANA820.4NANANA707.5NANANA508.2NANANA320.0NANANA672.7NANANA170.1NANANANANANANANANANA
 us-gaap:ConstructionInProgressGross us-gaap:PublicUtilityRegulatedOrUnregulatedStatus us-gaap:UnregulatedOperationNANA335.1NANANA24.8NANANA82.5NANANA157.4NANANA104.7NANANA150.2NANANA21.7NANANANANANANANANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ████▇▇▇▇▇▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▂▂▂▂▂▁▁▁▁▁▁▁9625.39481.49364.79308.69157.59042.38878.78807.78705.08589.08515.98589.38512.18819.88618.58525.58433.28312.88214.68141.58049.18005.97919.17930.67857.44560.84485.14449.24384.44323.84257.14202.04140.34098.44036.03972.43915.7
us-gaap:PropertyPlantAndEquipmentNet ███▇▇▇▇▇▆▆▆▆▆▆▆▆▅▅▅▅▅▅▅▅▅▁▁▁▁▁▁▁▁▁▁▁▁26266.425994.425707.424551.724171.823797.123620.123035.122535.822193.322000.921663.721078.421466.321347.020882.920524.319990.219915.519612.219398.919259.019189.718785.218529.411316.011257.711134.911024.010941.710906.610805.210704.510616.110572.210438.810340.7
us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures ██▇▇▇▆▆▆▅▅▄▃▂▂▁1782.01773.61764.31750.41744.71717.71720.81720.41696.51670.61665.31613.71596.61598.91553.4NANANA1443.9NANANA1380.9NANA431.1424.1423.3416.8409.6402.7396.7390.6383.0378.3372.5362.1
us-gaap:Goodwill ▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇██▁▁▁▁▁▁▁▁▁▁▁▁3052.83052.83052.83052.83052.83052.83052.83052.83052.83052.83052.83052.83052.83052.83053.53053.53053.53046.23046.23046.23046.22999.13023.53389.13386.5441.9441.9441.9441.9441.9441.9441.9441.9441.9441.9441.9441.9
 us-gaap:FiniteLivedIntangibleAssetsNet dei:LegalEntity wec:WECInfrastructureLLC█▄▁100.193.486.8NANANA9.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:FiniteLivedIntangibleAssetsNet dei:LegalEntity,us-gaap:FiniteLivedIntangibleAssetsByMajorClass wec:WECInfrastructureLLC,us-gaap:CustomerContracts█▄▁89.983.076.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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 us-gaap:FiniteLivedIntangibleAssetsNet dei:LegalEntity,us-gaap:FiniteLivedIntangibleAssetsByMajorClass wec:WECInfrastructureLLC,us-gaap:Swap▁▄█5.55.75.9NANANA6.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingLeaseRightOfUseAsset NANA20.7NANANA41.443.844.748.2NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent █▇▇▇▇▇█▆▆▆▅▆▆▆▅▄▄▄▃▃▃▃▃▄▃▂▁▂▂▂▂▁▁▁▁▁▁1005.7937.2896.5877.7848.9853.2957.8796.0803.5802.3704.1749.0753.5757.1619.9584.8549.7527.5461.0418.3419.9379.3403.9511.5455.7317.2200.3321.0321.4328.8322.5186.9185.1179.8204.2179.9180.8
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:AccountsPayableCurrent ▆▅█▆▆▅█▇▆▅█▆▆▅▇▆▆▄▇▅▅▅▇▇▇▁▂▂▁▃▂▁▁▁▂▁▁744.6656.0880.7751.3696.6597.9908.1769.0715.6674.1876.4690.4681.0592.8859.9743.9724.1582.3861.5663.5620.5584.4815.4777.6777.1291.9363.3315.0288.5435.0342.6296.9276.4257.1368.4277.7267.5
 us-gaap:AccruedLiabilitiesCurrent us-gaap:ConsolidatedEntities us-gaap:VariableInterestEntityPrimaryBeneficiary0.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LiabilitiesCurrent ▆▇█▅▇▅▆▅▆▅▆▇▆▇▇▆▅▃▄▃▄▄▅▅▅▂▃▁▁▂▂▂▂▂▂▂▂3373.93714.94148.12840.03484.62847.73182.72818.43362.02889.93331.73602.53053.23605.93869.33026.12787.32054.62431.62025.52137.12229.82709.02666.82940.31560.31668.71065.6980.81424.61496.41291.21280.71278.11443.31387.01428.4
us-gaap:LongTermDebtCurrent NANA777.7NANANA686.9NANANA360.1NANANANANANANANA89.495.8152.4157.7606.0608.4426.8424.147.745.1343.8342.2371.0414.6413.5412.1381.1334.8
 us-gaap:LongTermDebtCurrent us-gaap:ConsolidatedEntities us-gaap:VariableInterestEntityPrimaryBeneficiary4.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:OperatingLeaseLiabilityCurrent us-gaap:BalanceSheetLocation us-gaap:OtherCurrentLiabilitiesNANA3.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherLiabilitiesCurrent █▆▅▆▅▄▆▅▅▆▅▄▄█▆▄▄▄▄▂▃▄▅▅▆▂▁▁▁▁▁▁▁▂▁▁▁711.2568.5530.7547.6519.9443.9550.8503.4457.9578.7464.8393.9364.5747.5553.6442.6440.0421.3388.9240.2358.5375.3471.2466.8592.8219.8168.6155.7166.7150.3177.3170.7178.3219.1167.3173.5177.4
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:LiabilitiesNoncurrent █▇▆▆▅▅▅▅▄▄▄▂▂▁▁▂▁▂▂23390.622918.122217.522022.921064.721499.921514.521372.420424.020735.120301.419117.219128.218481.518229.418761.218589.118806.018731.4NANANA17961.0NANANANANANANANANANANANANANA
us-gaap:LongTermDebt NANA12450.5NANANA11858.3NANANA9994.0NANANA8746.6NANANANANANANANANANANA4552.4NANANA4626.7NANANA4772.9NANA
 us-gaap:LongTermDebt us-gaap:ConsolidatedEntities,us-gaap:FairValueByMeasurementBasis srt:ParentCompany,us-gaap:CarryingReportedAmountFairValueDisclosureNANA2754.8NANANA2541.6NANANA2190.8NANANA1892.3NANANANANANANANANANANANANANANANANANANANANANA
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 us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis us-gaap:CarryingReportedAmountFairValueDisclosure██▇▇▇▇▇▇▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▁▁▁▁▁▁▁▁13127.913041.812450.512184.111550.811844.811858.311541.510666.510670.610335.79464.29477.69549.39561.79467.59479.89272.79285.89139.98952.69055.49221.99300.79118.44543.14552.44554.74565.64617.84626.74659.74712.4NA4772.9NANA
 us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis us-gaap:EstimateOfFairValueFairValueDisclosure████▇▇▇▇▆▆▅▄▅▅▅▅▅▄▅▅▅▄▄▄▄▁▁▁▁▁▁▁▁14673.914139.014343.214007.913278.912920.813035.912751.711543.411257.510554.99762.19827.110054.510341.910135.210128.39730.29818.210248.49984.89790.59681.09386.49181.15157.85126.04979.74995.44954.24911.84951.75097.1NA5447.3NANA
us-gaap:LongTermDebtNoncurrent NANA11672.8NANANA11171.410897.39921.010326.79994.09119.09209.38617.58746.68785.88799.79143.69158.29088.18902.18955.89124.18727.08547.64169.24186.44569.64587.54348.84363.24370.94383.24441.04453.84240.64297.5
 us-gaap:LongTermDebtNoncurrent us-gaap:ConsolidatedEntities srt:ParentCompanyNANA2754.8NANANA2141.6NANANA2190.8NANANA1592.3NANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebtNoncurrent us-gaap:ConsolidatedEntities us-gaap:VariableInterestEntityPrimaryBeneficiary111.1NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebtNoncurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate▅▄██▄▁▁2412.72412.52512.22512.12412.52313.02312.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LongTermDebtAndCapitalLeaseObligations █▇▅▄▁▃▃12695.712317.711728.111652.510721.611194.711211.0NANANA9994.0NANANA8746.6NANANA9158.2NANANA9124.1NANANA4186.4NANANA4363.2NANANA4453.8NANA
us-gaap:DeferredIncomeTaxLiabilitiesNet █▇▅▄▃▂▁4269.64214.14059.83974.73945.93870.03769.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ▄▄▄▄▄▄▄▆▆▆▆▇▇█▅▇▆▆▇████▆▆▂▂▁▁▁▁▂▂▂▃▁▃314.2319.9327.0320.6322.2324.2326.2411.5414.0418.1422.8489.1490.4523.1397.4463.2451.0458.9498.6545.1541.9541.1543.1427.7428.0203.5203.8168.9169.3169.5173.2214.5225.2233.9244.0149.6251.6
us-gaap:OtherLiabilitiesNoncurrent ▆▆▆▅▅▅▅▅▅▅▅▆▆▆▆▆▆▆▆▆▅▅▅▅█▁▁▁▁▁▁▁▁▁▁▁▁1256.71236.31229.41128.61093.41106.01128.91116.41106.81109.81108.11233.41203.21191.41206.31194.41171.11161.01164.41167.01132.11067.21071.71034.41626.9294.2303.0273.2275.5280.2295.9289.9288.7276.4285.2298.7302.4
 us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:BalanceSheetLocation us-gaap:OtherNoncurrentLiabilitiesNANA32.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo NANA4.4NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree NANA4.5NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour NANA4.3NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive NANA3.8NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive NANA24.5NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
 us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities srt:ParentCompanyNANA10469.7NANANA10113.4NANANA9788.9NANANA9461.4NANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquity us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate█▇▆▅▄▁▁2317.52304.22292.12270.72258.12218.42214.6NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:AccumulatedOtherComprehensiveIncomeNANA-6.8NANANA-4.1NANANA-2.6NANANA2.9NANANA2.9NANANA4.6NANANA0.3NANANA0.3NANANA0.3NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:AdditionalPaidInCapitalNANA4143.7NANANA4186.6NANANA4250.1NANANA4278.5NANANA4309.8NANANA4347.2NANANA300.1NANANA349.7NANANA500.3NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:CommonStockNANA3.2NANANA3.2NANANA3.2NANANA3.2NANANA3.2NANANA3.2NANANA2.3NANANA2.3NANANA2.3NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:NoncontrollingInterestNANA162.4NANANA110.8NANANA23.4NANANA0.0NANANA0.0NANANA0.0NANANANANANANANANANANANANANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:ParentNANA10469.7NANANA10113.4NANANA9788.9NANANA9461.4NANANA8929.8NANANA8654.8NANANA4419.7NANANA4233.0NANANA4135.1NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:RetainedEarningsNANA6329.6NANANA5927.7NANANA5538.2NANANA5176.8NANANA4613.9NANANA4299.8NANANA4117.3NANANA3881.0NANANA3632.5NANA
 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents wec:TotalEquityNANA10662.5NANANA10254.6NANANA9842.7NANANA9491.8NANANA8960.2NANANA8685.2NANANANANANANANANANANANANANA
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest ██▇▆▆▆▅▅▅▄▃▃▃▃▂▁11030.410967.610662.510559.110492.710484.610254.610186.410148.310112.19842.79842.79756.29698.29491.89225.7NANA8960.2NANANANANANANANANANANANANANANANANANA
us-gaap:CommonStockValue ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█▅▅▅▅▅▅▄▄▄▄▄▄3.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.28456.74510.64419.74398.34367.14322.04233.04198.14195.44203.64135.14147.24081.1
us-gaap:AdditionalPaidInCapitalCommonStock ▁▁▁▄▄▅█4144.14143.64143.74163.84165.04167.34186.6NANANA4250.1NANANA4278.5NANANA4309.8NANANA4347.2NANANA300.1NANANANANANANANANANA
us-gaap:RetainedEarningsAccumulatedDeficit ██▇▇▇▇▆▆▅▅▅▅▄▄▄▃▃▃▂▂▂▂▁▁6688.26626.06329.66290.16222.86180.75927.75869.95821.75772.15538.25508.15449.15392.75176.84908.34857.04822.04613.94575.84515.04489.74299.84264.9NANA4117.0NANANANANANANANANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▂▂▁▁▁▁▂▁▁▂▃▅▅▆▅▅▅▅▅▅▅▅▆█-4.6-5.7-6.8-6.4-7.3-7.1-4.1-7.1-6.6-4.0-2.62.42.54.62.92.42.52.72.93.74.44.34.611.2NANA0.3NANANANANANANANANANA
us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders █▁0.90.4NA0.60.70.5NA0.60.9NANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:NetCashProvidedByUsedInOperatingActivities ▇▃▂▅▆▆▄▅▅▆▄▄▅█▃▄▅▆▃▄▄▆▂▃▃▃▁▂▃▃▁▃▃▃▁▃▂831.0395.2246.3570.1689.1690.5504.8549.5555.5735.7437.3494.8619.4894.0331.9478.7553.4714.6381.9497.8528.2695.9221.9357.3386.2329.7163.1313.3336.2385.1180.7368.8351.2330.3181.5383.7268.2
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆▂▆▆▆▅▅▆▆▅▅▆▆▅▆▅▇▆▇▇█▇▇▁█████████▇██-533.3-541.3-1243.7-556.9-543.2-463.0-760.4-668.1-459.8-606.6-664.4-723.2-561.0-435.8-702.1-528.1-698.3-325.6-512.6-392.5-260.7-188.4-326.7-416.7-1522.9-156.3-227.9-216.0-173.8-139.1-201.0-208.2-191.3-145.3-238.2-178.8-182.2
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▄▇▃▂▂▄▃▃▂▄▄▃▁▄▃▄▂▃▃▂▁▄▃█▂▃▃▂▂▃▂▂▂▃▂▃-287.6163.11008.8-14.4-149.2-244.1271.394.5-94.1-186.1333.0216.6-78.1-445.1375.531.0135.7-380.859.4-112.4-270.1-522.6251.4-132.81285.9-170.138.0-42.0-156.6-244.427.8-163.1-163.6-195.979.3-205.0-91.0
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▄▄▄▃▃▃▄▂▄▁█▃▃▄▄▃▃▃10.117.011.4-1.2-3.3-16.615.7-24.11.6-57.0105.9-11.8-19.713.120.1-19.8-15.10.7NANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:DepreciationDepletionAndAmortization ██▇▇▇▇▇▇▇▆▆▆▆▆▆▅▅▅▅▅▅▅▅▄▂▂▂▂▁▁▁▁▁▁▁▁▁266.2261.4249.3245.0242.5239.1236.2233.8229.9226.4217.7212.8206.7208.6205.1201.2197.7194.6193.1191.6190.0187.9179.2176.5105.7105.1103.5103.3101.4100.699.096.996.795.594.591.890.3
us-gaap:IncreaseDecreaseInAccountsPayable ▆▂▇▅▆▁█▅▅▂█▅▆▂▇▅▇▂▇▅▅▃▆▄▇▄▆▅▃▆▆▅▅▃▇▅▅62.2-181.5117.69.461.8-250.1193.830.4-18.4-204.3181.813.885.9-170.9119.72.898.7-212.7129.117.711.3-123.746.6-83.398.7-71.351.424.9-147.394.744.427.417.9-104.5100.33.722.1
us-gaap:IncreaseDecreaseInInventories ▇▂▄▇▆▂▄▇▇▁▄▇▇▂▃█▇▂▄█▅▁▄█▆▃▅▆▆▃▄▆▆▃▅▅▅99.2-175.1-44.8105.776.6-158.7-43.4131.9131.3-218.3-60.2141.690.4-163.0-133.4162.092.6-170.5-66.2159.723.7-217.2-32.0173.638.7-110.921.375.069.4-94.5-38.249.751.1-93.918.67.123.4
us-gaap:NetCashProvidedByUsedInOperatingActivities ▇▃▂▅▆▆▄▅▅▆▄▄▅█▃▄▅▆▃▄▄▆▂▃▃▃▁▂▃▃▁▃▃▃▁▃▂831.0395.2246.3570.1689.1690.5504.8549.5555.5735.7437.3494.8619.4894.0331.9478.7553.4714.6381.9497.8528.2695.9221.9357.3386.2329.7163.1313.3336.2385.1180.7368.8351.2330.3181.5383.7268.2
 us-gaap:NetIncomeLoss us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName wec:TransmissionAffiliate▃▃▃▄█▂█▂▁▁65.465.164.866.780.263.180.3999999999999861.560.058.5NANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:ProfitLoss ▃█▂▂▂▇▂▂▂▆▁275.7510.3239.6267.1242.1452.6244.2234.3235.8420.4206.2NANANA433.8NANANANANANANANANA80.9195.8121.4126.3133.0207.6144.3137.5119.0176.698.8156.1119.3
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆▂▆▆▆▅▅▆▆▅▅▆▆▅▆▅▇▆▇▇█▇▇▁█████████▇██-533.3-541.3-1243.7-556.9-543.2-463.0-760.4-668.1-459.8-606.6-664.4-723.2-561.0-435.8-702.1-528.1-698.3-325.6-512.6-392.5-260.7-188.4-326.7-416.7-1522.9-156.3-227.9-216.0-173.8-139.1-201.0-208.2-191.3-145.3-238.2-178.8-182.2
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▄▃█▄▄▃▇▄▃▂▆▄▃▃▄▃▃▂▃▃▂▂▃▃▁▁▂▁▁▁▁▁▁▁▂▁▁539.5470.61255.6581.5541.1496.11017.5656.3496.4358.8926.6575.0475.9439.6650.3519.2460.3329.7423.6381.4306.7312.0501.1408.6207.0149.5223.1207.5176.3129.2189.7190.4173.7133.6229.5163.5171.7
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▄▇▃▂▂▄▃▃▂▄▄▃▁▄▃▄▂▃▃▂▁▄▃█▂▃▃▂▂▃▂▂▂▃▂▃-287.6163.11008.8-14.4-149.2-244.1271.394.5-94.1-186.1333.0216.6-78.1-445.1375.531.0135.7-380.859.4-112.4-270.1-522.6251.4-132.81285.9-170.138.0-42.0-156.6-244.427.8-163.1-163.6-195.979.3-205.0-91.0
us-gaap:ProceedsFromIssuanceOfLongTermDebt ▃▄█▄▁▁▄▅▁▃▆▁▄▁▂▁418.8600.01563.6700.0110.00.0575.0970.00.0350.01140.00.0600.00.0225.00.0NANA200.0200.0NANA500.0200.0NANA0.00.0250.00.00.01.0250.00.0251.80.00.0
us-gaap:RepaymentsOfLongTermDebt ▃▁█▁▃▁▂▁▁▁▂▁▅▁▂▁▁▁▁▁▂▂▄▁▁▁▁▁▃▁▁▁▃▁▁▁▁326.514.71284.464.4404.214.0254.188.74.013.3258.913.0668.812.6127.612.32.612.052.511.7102.4139.4502.515.52.39.32.310.9302.28.933.053.7302.08.52.08.32.0
us-gaap:PaymentsOfDividendsCommonStock ██▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▅▅▅▅▅▃▂▂▂▂▂▂▂▂▁▁▁▁▁213.8213.7199.5199.5199.5199.5186.1186.1186.1186.2174.3174.3174.5174.2164.1164.1164.2164.1156.3156.2156.2156.2144.5120.495.295.388.088.087.988.186.686.777.877.868.969.169.2
us-gaap:PaymentsForRepurchaseOfCommonStock ▁▁▅▁▂▅▁▄▄█▄▃▁▂▂▃▃▃▁▂▄▇▂▄▂▃▅▄▁▆▄▆██▆▄▆4.76.642.56.49.940.41.931.935.670.730.422.24.015.810.720.919.520.22.411.434.659.68.634.18.623.439.026.94.752.635.552.269.266.548.228.047.8
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30

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
Value3.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.284564510441943984367432242334198419542034135414740814051396339403947390438023566
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 Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.029.629.829.129.929.929.228.729.229.329.428.930.029.429.328.629.730.229.629.128.1

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


Common
Period End2021-06-302020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value315315315315315315315315315315315315315315315315315315315315315315225225229230116116
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value316316316316316316316316316316316317317317316317317317229227227227227228230231232233233234236236236236236
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


Weighted
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value315315315315315315315315315315315315315315315315315315227225225225225226228228230230230232233233233233233
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312012-12-312012-09-302012-06-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.760.850.771.430.770.740.751.330.650.740.731.241.370.680.631.130.620.690.571.10.570.580.360.870.540.560.590.920.430.680.520.50.560.470.732.50.480.380.55
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312012-12-312012-09-302012-06-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.760.840.761.430.770.740.741.330.650.740.731.231.360.680.631.120.610.680.571.090.570.580.350.860.530.560.580.910.430.670.510.50.550.460.722.460.470.370.55
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Basic Share

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare

us-gaap:IncomeLossFromContinuingOperationsPerBasicShare


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.881.620.850.771.430.740.751.330.740.731.240.680.631.130.690.571.10.580.360.870.560.590.920.640.610.520.770.430.680.520.750.490.560.420.732.480.480.370.55
Percentage of IncomeLossFromContinuingOperationsPerBasicShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Income Loss From Continuing Operations Per Diluted Share

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare

us-gaap:IncomeLossFromContinuingOperationsPerDilutedShare


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.871.610.840.761.430.740.741.330.740.731.230.680.631.120.680.571.090.580.350.860.560.580.910.630.60.520.760.430.670.510.740.490.550.410.722.450.470.370.55
Percentage of IncomeLossFromContinuingOperationsPerDilutedShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value2775112382672414492462332334182002332283914332151983561932161813451721829219512112613311612910917112611288129
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.519.012.316.215.621.312.714.514.717.69.614.213.717.121.113.012.215.59.912.611.315.89.310.79.314.19.912.212.70.00.00.00.00.00.00.00.0

Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-600000.0-100000.0200000.0-200000.00-300000.0-200000.0000
Percentage of ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest100.0100.0100.0100.00.0100.0100.00.00.00.0
Percentage of Revenues-0.0-0.00.0-0.00.0-0.0-0.00.00.00.0

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

us-gaap:ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value27651123926824144924723323341920023322939243321519935619321618134617318292196
Percentage of ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.519.012.416.215.621.312.714.514.717.69.614.213.717.121.113.012.215.59.912.611.315.89.410.89.314.1

Cost Of Goods And Services Sold

us-gaap:CostOfGoodsAndServicesSold

us-gaap:CostOfGoodsAndServicesSold


Cost
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
Value52512656574824447346934844911009854524547972797542541941745554508838682590353613523407
Percentage of CostOfGoodsAndServicesSold100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues31.447.034.029.228.734.835.630.130.942.541.131.932.742.538.832.733.240.838.032.431.738.236.934.835.644.242.739.4

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1307206215621280120914821584129712751834178713411341
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues78.076.680.877.678.170.381.480.780.277.286.081.680.2

us-gaap:CostsAndExpenses us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value92958693979594949390
Percentage of CostsAndExpenses7.14.65.67.38.16.46.07.37.34.9
Percentage of Revenues5.53.54.55.66.34.54.95.95.93.8
Percentage of Revenues wec:TransmissionAffiliate49.750.40.049.548.051.00.051.251.450.9

Gains Losses On Extinguishment Of Debt

us-gaap:GainsLossesOnExtinguishmentOfDebt

us-gaap:GainsLossesOnExtinguishmentOfDebt


Gains
Period End2020-12-312020-10-31
Value-10.5-27.9
Percentage of GainsLossesOnExtinguishmentOfDebt100.0100.0
Percentage of Revenues0.00.0

us-gaap:GainsLossesOnExtinguishmentOfDebt us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


Gains
Period End2020-10-09
Value27
Percentage of GainsLossesOnExtinguishmentOfDebt0.0
Percentage of Revenues0.0
Percentage of Revenues us-gaap:SubsequentEvent0.0

Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-30
Value329585276314295542277245251485218250282478357345315570306345295559318293144318199206207337232218189277245185268199146
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues19.721.714.319.019.125.714.315.315.820.410.515.216.920.917.420.819.324.715.620.218.425.517.217.214.522.916.320.019.919.919.720.718.721.723.719.70.00.00.0

Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value267242452234235420233231390215
Percentage of IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.215.621.514.614.817.714.213.817.113.0

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
Value5474374653903311156513175188-75.312911521311112811321313711063122768074130868070100538966965669488967634771
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 Revenues3.22.81.92.83.54.31.70.71.02.70.61.03.13.9-3.77.87.19.35.77.57.19.77.56.56.48.86.37.87.17.77.37.76.97.95.08.67.00.00.00.00.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ProductOrService

us-gaap:PublicUtilities


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value39973599
Percentage of IncomeTaxExpenseBenefit73.8130.765.1110.7
Percentage of Revenues2.43.62.34.7
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value16411239
Percentage of IncomeTaxExpenseBenefit29.655.322.743.9
Percentage of Revenues1.01.50.81.9
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value0.88.41.08.9
Percentage of IncomeTaxExpenseBenefit1.511.21.99.9
Percentage of Revenues0.00.30.10.4
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value23482151
Percentage of IncomeTaxExpenseBenefit42.764.240.556.9
Percentage of Revenues1.41.81.42.4
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Income
Period End2021-06-302021-03-312020-06-302020-03-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value4.1-32.9-6.9-30.7-19.2-6.0-9.1-5.1-7.3-7.1-7.3-4.9-6.2-7.5-8.0-5.1-5.6-6.5-9.0-4.3-8.6
Percentage of IncomeTaxExpenseBenefit7.6-43.9-12.8-34.1-30.4-4.9-11.8-6.4-9.8-5.4-8.4-6.1-8.8-7.5-14.9-5.7-8.4-6.7-16.0-6.2-17.7
Percentage of Revenues0.2-1.2-0.4-1.5-1.9-0.4-0.7-0.5-0.7-0.4-0.6-0.5-0.6-0.6-0.7-0.5-0.60.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther4100.0-32900.0-766.7-6140.0-3840.0-2000.00.0-1700.0-2433.3-2366.70.0-1225.0-2066.7-2500.00.0-1700.0-1866.70.00.00.00.0

wec:ElectricTransmissionSegment


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value9.49.8149.9
Percentage of IncomeTaxExpenseBenefit17.413.127.011.0
Percentage of Revenues0.60.40.90.5
Percentage of Revenues wec:ElectricTransmissionSegment0.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value0.70.11111
Percentage of IncomeTaxExpenseBenefit1.30.120.812.4
Percentage of Revenues0.00.00.70.5
Percentage of Revenues wec:NonUtilityEnergyInfrastructure0.50.18.98.6

Income Taxes Paid Net

us-gaap:IncomeTaxesPaidNet

us-gaap:IncomeTaxesPaidNet


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-30.72.555-37.6-1.2119.50.3140.2-39.68.347-0.32.12.2-0.6-8.9-28.0-4.3-7.80.47.3-1.0-1.34.30.04.47.610.02.015-46.4-13.3-24.6-24.84.74510214
Percentage of IncomeTaxesPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-1.80.12.9-2.3-0.10.50.50.00.90.0-1.90.52.9-0.00.10.1-0.0-0.4-1.4-0.3-0.50.00.4-0.1-0.10.30.00.40.70.60.20.00.00.00.00.00.00.00.00.0

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
Value1201191171221241291271251241241171121081061051031011041029910010010510362595960596261626365666061585856576351525349
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 Revenues7.24.46.17.48.06.16.57.87.85.25.76.86.54.75.16.36.24.55.25.86.24.65.76.16.34.34.95.85.73.75.25.96.35.16.25.96.50.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination


Interest
Period End2021-06-302021-03-312020-06-302020-03-31
Value-85.2-85.7-86.8-87.1
Percentage of InterestExpense-71.0-71.7-69.8-67.3
Percentage of Revenues-5.1-3.2-5.6-4.1
Percentage of Revenues us-gaap:IntersegmentElimination0.00.00.00.0

us-gaap:InterestExpense us-gaap:ProductOrService

us-gaap:PublicUtilities


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value157158157157158161160159158160696462636261
Percentage of InterestExpense131.6132.3133.8129.0127.5124.7126.3127.1127.7129.058.957.658.059.859.459.5
Percentage of Revenues9.45.98.29.510.27.68.29.910.06.83.33.93.82.83.03.7
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value16161515161615141314131212121211
Percentage of InterestExpense13.813.813.412.812.912.412.311.711.211.911.711.411.311.511.410.6
Percentage of Revenues1.00.60.80.91.00.80.80.90.90.60.70.80.70.50.60.7
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1.51.52.82.72.52.22.02.31.92.32.42.12.12.12.22.3
Percentage of InterestExpense1.21.32.42.22.01.71.61.81.51.82.01.91.92.02.12.2
Percentage of Revenues0.10.10.10.20.20.10.10.10.10.10.10.10.10.10.10.1
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value139140139139140143143142142143534948494848
Percentage of InterestExpense116.5117.2118.0114.0112.5110.6112.4113.6115.0115.345.144.344.746.345.946.7
Percentage of Revenues8.35.27.28.49.06.87.38.99.06.02.63.02.92.22.42.9
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value2424253032353335363534323028262526292929303133311412121212121212121213121213131313
Percentage of InterestExpense20.520.322.024.926.227.126.328.529.428.229.329.427.926.224.724.526.327.828.930.030.231.031.730.222.520.420.120.520.719.620.420.619.919.720.321.221.022.223.223.223.2
Percentage of Revenues1.50.91.31.82.11.71.72.22.31.51.72.01.81.21.31.51.61.31.51.71.91.41.81.81.40.91.01.21.20.71.11.21.21.01.31.21.40.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther24600.024200.00.05066.73622.27020.00.02761.54055.62064.70.01370.8977.42000.00.0453.6837.51003.40.0742.5686.4263.00.0112.22800.04066.70.04133.34066.74066.70.03200.04200.04266.70.04300.04300.00.00.00.00.0

us-gaap:IntersegmentElimination


Interest
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-85.7-86.8-87.1-87.0-88.5-89.1-89.5-2.1-1.3-0.7-1.20.70.4-1.1-1.8-1.9-2.0-2.0-2.7-2.7-2.1-0.2-0.1
Percentage of InterestExpense-70.2-69.8-67.3-68.4-70.3-71.8-71.9-1.8-1.2-0.6-1.10.70.4-1.1-1.7-1.9-2.0-2.0-2.7-2.6-2.0-0.3-0.2
Percentage of Revenues-5.2-5.6-4.1-4.5-5.5-5.6-3.8-0.1-0.1-0.0-0.10.00.0-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.0-0.0
Percentage of Revenues us-gaap:IntersegmentElimination0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:ElectricTransmissionSegment


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value4.84.94.84.94.94.84.83.02.72.60.30.00.00.00.00.00.00.00.00.00.0
Percentage of InterestExpense4.04.14.14.03.93.73.82.42.22.10.30.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.20.20.30.30.20.20.20.20.10.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues wec:ElectricTransmissionSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1718151515151515151515151616161615151515
Percentage of InterestExpense14.915.113.112.312.111.812.112.312.512.613.314.214.715.115.315.614.914.614.915.7
Percentage of Revenues1.10.70.80.91.00.70.81.01.00.70.81.01.00.70.81.00.90.70.80.9
Percentage of Revenues wec:NonUtilityEnergyInfrastructure13.413.10.012.112.111.80.013.012.612.30.013.813.713.60.0119.10.00.00.0251.6

Interest Paid Net

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value16376160801668516870181661636214768155481525615151168401783496209721101211031810621103199126951311212960.1
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues9.72.98.34.810.84.18.64.411.42.87.93.88.83.07.63.09.42.57.73.010.51.99.72.09.71.58.02.09.71.38.81.810.51.79.61.99.70.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:NetIncomeLoss

wec:TransmissionAffiliate


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value65656466806380616058
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues3.92.43.44.05.23.04.13.83.82.5
Percentage of Revenues wec:TransmissionAffiliate35.234.50.035.539.533.80.033.332.932.9

Net Income Loss Attributable To Noncontrolling Interest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest


Net
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-600000.0-100000.0200000.0-200000.00-300000.0-200000.00000
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.00.0100.0100.00.00.00.00.0
Percentage of Revenues-0.0-0.00.0-0.00.0-0.0-0.00.00.00.00.0

us-gaap:NetIncomeLossAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Net
Period End2021-06-302021-03-312020-06-302020-03-312019-09-302019-06-30
Value-600000.0-100000.0200000.0-200000.0-300000.0-200000.0
Percentage of NetIncomeLossAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0
Percentage of Revenues-0.0-0.00.0-0.0-0.0-0.0
Percentage of Revenues us-gaap:NoncontrollingInterest0.00.00.00.00.00.0

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value27651023926624145224323423542020523323139043221519935619421718134617918280195121126133207
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.519.012.416.215.621.512.514.614.817.79.914.213.817.121.113.012.215.59.912.711.315.89.710.78.214.19.912.212.712.2

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:ProductOrService

us-gaap:PublicUtilities


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value192393164380
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic69.877.168.284.0
Percentage of Revenues11.514.610.618.0
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value4311232107
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic15.822.013.323.7
Percentage of Revenues2.64.22.15.1
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value2.5242.826
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic0.94.81.25.8
Percentage of Revenues0.10.90.21.2
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value146256129246
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic53.150.253.754.5
Percentage of Revenues8.79.58.411.7
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value-12.417-21.4-18.3
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic-4.53.5-8.9-4.0
Percentage of Revenues-0.70.7-1.4-0.9
Percentage of Revenues us-gaap:CorporateAndOther-12400.017600.0-2377.8-3660.0

wec:ElectricTransmissionSegment


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value27283325
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic9.85.513.95.5
Percentage of Revenues1.61.02.21.2
Percentage of Revenues wec:ElectricTransmissionSegment0.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Net
Period End2021-06-302021-03-312020-06-302020-03-31
Value68716465
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic24.914.026.814.5
Percentage of Revenues4.12.74.23.1
Percentage of Revenues wec:NonUtilityEnergyInfrastructure51.551.951.750.5

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:StatementEquityComponents

us-gaap:Parent


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value276510266241452234235420233231390
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.519.016.215.621.514.614.817.714.213.817.1
Percentage of Revenues us-gaap:Parent0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value276510266241452234235420233231390
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.519.016.215.621.514.614.817.714.213.817.1
Percentage of Revenues us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.0

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
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-39000000.0-44100000.0-93700000.0-56200000.0-42900000.0-84000000.0-85400000.0-65300000.0-63600000.0-57400000.0-71100000.0-52200000.0-48400000.0-66400000.0-54500000.0-48200000.0-47000000.0-47100000.0-55600000.0-53300000.0-36800000.0-29700000.0-61400000.0-52700000.0-21400000.0-40300000.0-44100000.0-39500000.0
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-2.3-1.6-4.8-3.4-2.8-4.0-4.4-4.1-4.0-2.4-3.4-3.2-2.9-2.9-2.7-2.9-2.9-2.0-2.8-3.1-2.3-1.4-3.3-3.1-2.2-2.9-3.6-3.8

us-gaap:NonoperatingIncomeExpense us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value-28100000.0-28500000.0-28800000.0-28100000.0-25400000.0-28500000.0-24400000.0-28700000.0-28600000.0-28800000.0
Percentage of NonoperatingIncomeExpense72.164.630.750.059.233.928.644.045.050.2
Percentage of Revenues-1.7-1.1-1.5-1.7-1.6-1.4-1.3-1.8-1.8-1.2
Percentage of Revenues wec:TransmissionAffiliate-15.1-15.10.0-15.0-12.5-15.30.0-15.5-15.7-16.2

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
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
Value368629370370338626363310314542289302330545412393362617361399332589380345165358243246240381271258229321201280222295193224174295215203163228
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues22.023.419.222.421.929.718.619.319.822.814.018.419.823.820.123.722.226.818.423.320.726.820.620.416.725.919.923.823.122.523.124.522.725.218.827.023.60.00.00.00.00.00.00.00.00.0

us-gaap:OperatingIncomeLoss us-gaap:ProductOrService

us-gaap:PublicUtilities


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value371343625374313317541210211244457309288
Percentage of OperatingIncomeLoss100.4101.399.9103.2100.8100.999.772.869.974.083.975.273.4
Percentage of Revenues22.522.229.719.219.520.022.810.212.914.620.015.117.4
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingIncomeLoss us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value24591618624421375115411476514
Percentage of OperatingIncomeLoss6.617.625.823.98.013.525.417.65.112.627.115.83.6
Percentage of Revenues1.53.87.74.41.52.75.82.50.92.56.53.20.9
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-2.06.03721-2.24.64129-5.48.13619-3.0
Percentage of OperatingIncomeLoss-0.51.86.05.9-0.71.57.610.3-1.82.46.64.7-0.8
Percentage of Revenues-0.10.41.81.1-0.10.31.71.4-0.30.51.60.9-0.2
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value349277426266290270361130201195273225277
Percentage of OperatingIncomeLoss94.381.968.173.593.585.966.744.966.559.050.254.770.5
Percentage of Revenues21.117.920.213.718.117.015.26.312.311.712.011.016.7
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingIncomeLoss us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value-6.9-9.0-4.2-17.4-6.0-7.1-3.9-9.9-0.4-6.5-5.4-2.11.1-6.2-1.2-3.6-4.5-1.6-0.3-9.3-3.9-68.1-9.3-13.1-5.9-6.2-1.1-2.4-1.8-1.0-1.2-1.7-1.9-1.3-1.3-2.3-1.1-1.6
Percentage of OperatingIncomeLoss-1.9-2.7-0.7-4.8-1.9-2.3-0.7-3.4-0.1-2.0-1.0-0.50.3-1.7-0.2-1.0-1.1-0.5-0.1-2.4-1.1-41.1-2.6-5.4-2.4-2.6-0.3-0.9-0.7-0.4-0.4-0.8-0.7-0.6-0.4-1.2-0.5-0.9
Percentage of Revenues-0.4-0.6-0.2-0.9-0.4-0.4-0.2-0.5-0.0-0.4-0.2-0.10.1-0.4-0.1-0.2-0.3-0.1-0.0-0.5-0.2-6.9-0.7-1.1-0.6-0.6-0.1-0.2-0.2-0.1-0.1-0.2-0.2-0.10.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther-1150.0-1000.0-840.00.0-461.5-788.9-229.40.0-16.7-209.7-385.70.019.6-193.8-41.40.0-112.5-36.4-2.50.0-14.0-13620.0-3100.00.0-1966.7-2066.7-366.70.0-450.0-333.3-400.00.0-633.3-433.30.00.00.00.0

us-gaap:IntersegmentElimination


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-85.7-86.7-86.5-86.6-86.8-87.0-87.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of OperatingIncomeLoss-23.1-25.6-13.8-23.9-27.9-27.7-16.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues-5.2-5.6-4.1-4.4-5.4-5.5-3.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues us-gaap:IntersegmentElimination0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value919191929091928891929310110398979493
Percentage of OperatingIncomeLoss24.727.014.625.429.029.017.130.630.327.917.124.526.327.315.826.123.5
Percentage of Revenues5.55.94.34.75.65.73.94.35.65.54.14.96.26.04.24.85.5
Percentage of Revenues wec:NonUtilityEnergyInfrastructure73.972.970.60.075.674.072.50.079.579.078.70.0760.30.00.00.01511.3

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-30
Value1.11.1-0.40.9-0.2-3.03.0-0.5-2.6-1.4-5.0-0.1-2.11.70.5-0.1-0.2-0.2-0.8-0.70.1-0.3-6.6-0.4110.00.00.00.00.00.00.00.00.00.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.10.0-0.00.1-0.0-0.10.2-0.0-0.2-0.1-0.2-0.0-0.10.10.0-0.0-0.0-0.0-0.0-0.00.0-0.0-0.4-0.01.10.00.00.00.00.00.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.11.10.9-0.2-3.0-0.5-2.6-1.4-5.6-0.1-2.11.7
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0112.0100.0100.0100.0
Percentage of Revenues0.10.00.1-0.0-0.1-0.0-0.2-0.1-0.3-0.0-0.10.1
Percentage of Revenues us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Parent


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.11.10.9-0.2-3.0-0.5-2.6-1.4-5.6-0.1-2.11.7
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0112.0100.0100.0100.0
Percentage of Revenues0.10.00.1-0.0-0.1-0.0-0.2-0.1-0.3-0.0-0.10.1
Percentage of Revenues us-gaap:Parent0.00.00.00.00.00.00.00.00.00.00.00.0

Other Nonoperating Income Expense

us-gaap:OtherNonoperatingIncomeExpense

us-gaap:OtherNonoperatingIncomeExpense


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value39321925285.6252123305.326317.5191613158.27.532321811263.01.32.98.11.13.55.15.84.41.29.08.61619161412149.69.76.2
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.41.21.01.61.80.31.31.41.51.30.31.61.90.30.91.00.80.70.40.42.01.51.00.72.60.20.10.30.80.10.30.50.60.30.10.90.90.00.00.00.00.00.00.00.00.0

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value275510239267242452244234235420206433801951211261332071441371191769815611917211612910917012511288
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.419.012.416.215.621.512.514.614.817.79.921.18.214.19.912.212.712.212.213.111.813.89.215.012.60.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss us-gaap:ProductOrService

us-gaap:PublicUtilities


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value192393165380
Percentage of ProfitLoss70.077.168.284.1
Percentage of Revenues11.514.610.718.0
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.0

us-gaap:ProfitLoss us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value4311232107
Percentage of ProfitLoss15.822.013.323.7
Percentage of Revenues2.64.22.15.1
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value2.5242.826
Percentage of ProfitLoss0.94.81.25.8
Percentage of Revenues0.10.90.21.2
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value146256130247
Percentage of ProfitLoss53.250.353.754.6
Percentage of Revenues8.89.58.411.7
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.0

us-gaap:ProfitLoss us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Profit
Period End2021-06-302021-03-312020-06-302020-03-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value-12.417-21.4-18.38219712112613220714413711817698156119172115129109
Percentage of ProfitLoss-4.53.4-8.8-4.0101.5100.699.9100.099.9100.0100.099.999.9100.099.3100.0100.0100.399.999.9100.0
Percentage of Revenues-0.70.7-1.4-0.98.314.29.912.212.712.212.213.011.713.89.215.012.60.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther-12400.017600.0-2377.8-3660.016420.065666.70.042100.044300.069166.70.034350.039633.358866.70.052033.339766.70.00.00.00.0

wec:ElectricTransmissionSegment


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value27283325
Percentage of ProfitLoss9.85.513.85.5
Percentage of Revenues1.61.02.21.2
Percentage of Revenues wec:ElectricTransmissionSegment0.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value68716565
Percentage of ProfitLoss24.714.026.814.4
Percentage of Revenues4.12.64.23.1
Percentage of Revenues wec:NonUtilityEnergyInfrastructure51.151.851.950.4

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, us-gaap:ProductOrService, wec:TypesofOperatingRevenues

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

srt:ConsolidationEliminations, us-gaap:NaturalGasUsRegulated, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-8.7-13.3-8.2-14.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0
Percentage of Revenues-0.5-0.5-0.5-0.7
Percentage of Revenues srt:ConsolidationEliminations us-gaap:NaturalGasUsRegulated us-gaap:RevenueFromContractWithCustomer0.00.00.00.0

srt:ConsolidationEliminations, us-gaap:PublicUtilities, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-8.7-13.3-8.2-14.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0
Percentage of Revenues-0.5-0.5-0.5-0.7
Percentage of Revenues srt:ConsolidationEliminations us-gaap:PublicUtilities us-gaap:RevenueFromContractWithCustomer0.00.00.00.0

srt:ConsolidationEliminations, wec:Othernonutilityrevenues, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-3.9-1.6-3.9-1.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax44.812.047.611.3
Percentage of Revenues-0.2-0.1-0.3-0.1
Percentage of Revenues srt:ConsolidationEliminations wec:Othernonutilityrevenues us-gaap:RevenueFromContractWithCustomer0.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ConsolidationItems, wec:TypesofOperatingRevenues

srt:ConsolidationEliminations, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-12.6-14.9-12.1-15.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax144.8112.0147.6111.3
Percentage of Revenues-0.8-0.6-0.8-0.7
Percentage of Revenues srt:ConsolidationEliminations us-gaap:RevenueFromContractWithCustomer0.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:MajorCustomers, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues

wec:CommercialandIndustrialCustomer, us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value5110264283691712945116802947109
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-592.0-772.20.00.0-445.1-648.20.00.00.00.00.00.00.00.0
Percentage of Revenues3.13.83.31.72.44.33.71.82.84.93.91.82.84.8
Percentage of Revenues wec:CommercialandIndustrialCustomer us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:CommercialandIndustrialCustomer, us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value1743371016514411207244121864
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-198.9-330.10.00.0-202.4-366.70.00.00.00.00.00.00.00.0
Percentage of Revenues1.01.61.90.61.12.52.30.71.33.02.10.81.12.8
Percentage of Revenues wec:CommercialandIndustrialCustomer us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:CommercialandIndustrialCustomer, us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value1593236710029470121387
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1827.6-2428.60.0-1220.7-2087.90.00.00.0
Percentage of Revenues9.512.04.16.514.04.47.616.3
Percentage of Revenues wec:CommercialandIndustrialCustomer us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

wec:CommercialandIndustrialCustomer, us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value90176111284715113430551991503563187
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1036.8-1326.30.00.0-573.2-1073.00.00.00.00.00.00.00.00.0
Percentage of Revenues5.46.65.81.73.07.26.91.93.58.47.22.13.88.2
Percentage of Revenues wec:CommercialandIndustrialCustomer us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:DowntownMilwaukeeSteamCustomers, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value4.2146.32.54.18.46.52.44.3107.22.74.59.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-48.3-111.30.00.0-50.0-59.60.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.50.30.20.30.40.30.10.30.40.30.20.30.4
Percentage of Revenues wec:DowntownMilwaukeeSteamCustomers us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Largecommercialandindustrialcustomers, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value224209195244187194203237217212217249241203
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2580.5-1575.20.00.0-2290.2-1380.10.00.00.00.00.00.00.00.0
Percentage of Revenues13.47.810.114.812.19.210.514.813.78.910.415.214.48.9
Percentage of Revenues wec:Largecommercialandindustrialcustomers us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Otherretailcustomer, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value6.97.87.96.96.97.37.66.97.37.87.57.57.27.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-79.3-58.60.00.0-84.1-51.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.40.30.40.40.40.30.40.40.50.30.40.50.40.3
Percentage of Revenues wec:Otherretailcustomer us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Otherutility, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value6.05.41.44.95.38.58.815102.5132.20.42.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-69.0-40.60.00.0-64.6-60.30.00.00.00.00.00.00.00.0
Percentage of Revenues0.40.20.10.30.30.40.51.00.70.10.70.10.00.1
Percentage of Revenues wec:Otherutility us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Otherutility, us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value-33.3182121614-13.4-5.2-1.2-13.2-12.8147.88.2-12.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax382.8-1373.70.00.0-174.495.00.00.00.00.00.00.00.00.0
Percentage of Revenues-2.06.80.61.00.9-0.6-0.3-0.1-0.8-0.50.70.50.5-0.5
Percentage of Revenues wec:Otherutility us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Otherutility, us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value5.1823.08.8-1.2-17.7-5.94.2-2.1-23.14.68.35.5-25.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-58.6-622.60.00.014.6125.50.00.00.00.00.00.00.00.0
Percentage of Revenues0.33.10.20.5-0.1-0.8-0.30.3-0.1-1.00.20.50.3-1.1
Percentage of Revenues wec:Otherutility us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Otherutility, us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-112.13445631-60.74013-76.56242-84.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1288.5-2589.50.0-379.3430.50.00.00.00.00.00.0
Percentage of Revenues-6.712.83.42.0-2.92.50.9-3.23.82.5-3.7
Percentage of Revenues wec:Otherutility us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.0

wec:Otherutility, us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value-83.9785.53118-29.6-32.23729-40.6-18.84628-47.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax964.4-593.20.00.0-219.5209.90.00.00.00.00.00.00.00.0
Percentage of Revenues-5.02.90.31.91.2-1.4-1.72.31.8-1.7-0.92.81.7-2.1
Percentage of Revenues wec:Otherutility us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:ResaleCustomers, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value3762233328454329494052402573
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-429.9-471.40.00.0-346.3-320.60.00.00.00.00.00.00.00.0
Percentage of Revenues2.22.31.22.01.82.12.21.83.11.72.52.51.53.2
Percentage of Revenues wec:ResaleCustomers us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Residentialcustomer, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value419423419500418404390454356406393465393384
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4816.1-3185.70.00.0-5106.1-2871.60.00.00.00.00.00.00.00.0
Percentage of Revenues25.015.721.730.327.019.220.128.322.417.118.928.323.516.8
Percentage of Revenues wec:Residentialcustomer us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Residentialcustomer, us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value199333233128157282232117154354268112163332
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2288.5-2510.50.00.0-1919.5-2006.40.00.00.00.00.00.00.00.0
Percentage of Revenues11.912.412.17.810.213.411.97.39.714.912.96.99.814.5
Percentage of Revenues wec:Residentialcustomer us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Residentialcustomer, us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value378766184095712239125822037123
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-435.6-660.90.00.0-487.8-675.90.00.00.00.00.00.00.00.0
Percentage of Revenues2.33.33.41.12.64.53.71.42.55.34.01.22.35.4
Percentage of Revenues wec:Residentialcustomer us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Residentialcustomer, us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value425769222323691209319863
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-4892.0-5785.00.0-3941.5-4902.80.00.00.0
Percentage of Revenues25.428.613.420.932.813.020.136.3
Percentage of Revenues wec:Residentialcustomer us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

wec:Residentialcustomer, us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value188347239741253132586912638327771128356
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2167.8-2613.50.00.0-1534.1-2220.60.00.00.00.00.00.00.00.0
Percentage of Revenues11.312.912.44.58.114.813.34.37.916.113.44.47.715.6
Percentage of Revenues wec:Residentialcustomer us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Smallcommercialandindustrial, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value346331321373307323333385331333336388353330
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3983.9-2491.70.00.0-3745.1-2295.00.00.00.00.00.00.00.00.0
Percentage of Revenues20.712.316.622.619.815.317.124.020.814.016.223.621.114.5
Percentage of Revenues wec:Smallcommercialandindustrial us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalRetailCustomers, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value997972944112592093093510859139609531110995926
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-11459.8-7311.30.00.0-11225.6-6598.60.00.00.00.00.00.00.00.0
Percentage of Revenues59.536.148.868.259.444.148.167.557.440.445.967.659.540.5
Percentage of Revenues wec:TotalRetailCustomers us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalRetailCustomers, us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value250436297157193374303146199470349142211442
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2880.5-3282.70.00.0-2364.6-2654.60.00.00.00.00.00.00.00.0
Percentage of Revenues15.016.215.49.512.517.815.69.112.519.816.88.612.619.3
Percentage of Revenues wec:TotalRetailCustomers us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalRetailCustomers, us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value55131104295614711534591971263256187
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-634.5-991.00.00.0-690.2-1042.60.00.00.00.00.00.00.00.0
Percentage of Revenues3.34.95.41.83.77.06.02.13.88.36.12.03.48.2
Percentage of Revenues wec:TotalRetailCustomers us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalRetailCustomers, us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value58410922894239852804411251
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6719.5-8213.50.0-5162.2-6990.80.00.00.0
Percentage of Revenues34.940.617.527.346.717.427.752.6
Percentage of Revenues wec:TotalRetailCustomers us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

wec:TotalRetailCustomers, us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value27852435010217246439299182583428106191544
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3204.6-3939.80.00.0-2107.3-3293.60.00.00.00.00.00.00.00.0
Percentage of Revenues16.619.518.16.211.222.020.26.211.424.520.66.511.523.8
Percentage of Revenues wec:TotalRetailCustomers us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Transportationcustomers, us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value4874564046726744468768435477
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-560.9-557.90.00.0-564.6-515.60.00.00.00.00.00.00.00.0
Percentage of Revenues2.92.82.92.43.03.43.42.82.93.73.32.63.33.4
Percentage of Revenues wec:Transportationcustomers us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Transportationcustomers, us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value6.6118.75.37.0108.65.66.311104.96.89.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-75.9-82.70.00.0-85.4-74.50.00.00.00.00.00.00.00.0
Percentage of Revenues0.40.40.40.30.50.50.40.30.40.50.50.30.40.4
Percentage of Revenues wec:Transportationcustomers us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Transportationcustomers, us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value7310961701076469120
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-841.4-824.10.0-857.3-761.00.00.00.0
Percentage of Revenues4.44.13.74.55.14.04.45.1
Percentage of Revenues wec:Transportationcustomers us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

wec:Transportationcustomers, us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value1724221517242014162119131621
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-204.6-183.50.00.0-207.3-170.90.00.00.00.00.00.00.00.0
Percentage of Revenues1.10.91.21.01.11.11.00.91.00.90.90.81.00.9
Percentage of Revenues wec:Transportationcustomers us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Wholesalecustomer, us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value3839444641424453444734625854
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-443.7-298.50.00.0-503.7-298.60.00.00.00.00.00.00.00.0
Percentage of Revenues2.31.52.32.82.72.02.33.32.82.01.73.83.52.4
Percentage of Revenues wec:Wholesalecustomer us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues

us-gaap:ElectricityUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value1083109510191212999103410381185102110611062121810841067
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12450.6-8233.10.00.0-12190.2-7337.60.00.00.00.00.00.00.00.0
Percentage of Revenues64.640.752.773.564.549.153.373.764.344.751.174.164.846.7
Percentage of Revenues us-gaap:ElectricityUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ElectricityUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value1083109510191212999103410381185102110611062121810841067
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12450.6-8233.10.00.0-12190.2-7337.60.00.00.00.00.00.00.00.0
Percentage of Revenues64.640.752.773.564.549.153.373.764.344.751.174.164.846.7
Percentage of Revenues us-gaap:ElectricityUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value266693366213254433365190232544432193273507
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3058.6-5214.30.00.0-3103.7-3075.20.00.00.00.00.00.00.00.0
Percentage of Revenues15.925.819.012.916.420.618.711.814.622.920.811.816.422.2
Percentage of Revenues us-gaap:NaturalGasUsRegulated wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value66225115436213911843641851404568172
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-769.0-1696.20.00.0-761.0-991.50.00.00.00.00.00.00.00.0
Percentage of Revenues4.08.46.02.64.06.66.12.74.07.86.82.84.17.6
Percentage of Revenues us-gaap:NaturalGasUsRegulated wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value54515468604075241032864384524129410024065791198
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6272.4-11627.10.00.0-6398.8-7321.30.00.00.00.00.00.00.00.0
Percentage of Revenues32.657.544.524.733.949.044.423.933.054.548.224.734.652.4
Percentage of Revenues us-gaap:NaturalGasUsRegulated wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value212627378150207458380151227564428167236518
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2444.8-4716.50.00.0-2534.1-3254.60.00.00.00.00.00.00.00.0
Percentage of Revenues12.723.319.69.113.421.819.69.414.323.820.610.214.122.7
Percentage of Revenues us-gaap:NaturalGasUsRegulated wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value266693366213254433365190232544432193273507
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3058.6-5214.30.00.0-3103.7-3075.20.00.00.00.00.00.00.00.0
Percentage of Revenues15.925.819.012.916.420.618.711.814.622.920.811.816.422.2
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value66225115436213911843641851404568172
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-769.0-1696.20.00.0-761.0-991.50.00.00.00.00.00.00.00.0
Percentage of Revenues4.08.46.02.64.06.66.12.74.07.86.82.84.17.6
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value16282641187916191524206619031570154623562064162416632266
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-18723.0-19860.20.00.0-18589.0-14658.90.00.00.00.00.00.00.00.0
Percentage of Revenues97.298.197.298.198.498.097.797.797.299.199.498.999.499.1
Percentage of Revenues us-gaap:PublicUtilities wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value12951722139713631207149314191336124916261491138513201585
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-14895.4-12949.60.00.0-14724.4-10592.20.00.00.00.00.00.00.00.0
Percentage of Revenues77.364.072.382.678.070.872.983.178.668.471.884.379.069.4
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.10.00.00.00.00.00.10.00.10.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.0-0.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues wec:Othernonutilityrevenues wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value4.44.74.34.24.24.44.14.24.24.14.34.03.93.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-50.6-35.30.00.0-51.2-31.20.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.20.20.30.30.20.20.30.30.20.20.20.20.2
Percentage of Revenues wec:Othernonutilityrevenues wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value4.44.74.24.34.24.44.14.24.24.24.34.14.03.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-50.6-35.30.00.0-51.2-31.20.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.20.20.30.30.20.20.30.30.20.20.20.20.2
Percentage of Revenues wec:Othernonutilityrevenues wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues

us-gaap:NaturalGasUsRegulated, srt:ConsolidationEliminations, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-8.3-8.2-14.1-8.4-9.1-14.7-12.7-12.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0100.0100.00.00.00.00.00.0
Percentage of Revenues-0.5-0.5-0.7-0.5-0.6-0.6-0.8-0.8
Percentage of Revenues us-gaap:NaturalGasUsRegulated srt:ConsolidationEliminations us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, wec:NonUtilityEnergyInfrastructure, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value9.414129.18.714128.99.8161010.010.014
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-108.0-109.80.00.0-106.1-102.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.60.50.60.60.60.70.60.60.60.70.50.60.60.7
Percentage of Revenues us-gaap:NaturalGasUsRegulated wec:NonUtilityEnergyInfrastructure us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, srt:ConsolidationEliminations, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-8.3-8.2-14.1-8.4-9.1-14.7-12.7-12.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0100.0100.00.00.00.00.00.0
Percentage of Revenues-0.5-0.5-0.7-0.5-0.6-0.6-0.8-0.8
Percentage of Revenues us-gaap:PublicUtilities srt:ConsolidationEliminations us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, wec:NonUtilityEnergyInfrastructure, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value9.414129.18.714128.99.8161010.010.014
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-108.0-109.80.00.0-106.1-102.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.60.50.60.60.60.70.60.60.60.70.50.60.60.7
Percentage of Revenues us-gaap:PublicUtilities wec:NonUtilityEnergyInfrastructure us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, srt:ConsolidationEliminations, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-1.6-3.9-1.6-0.7-3.1-0.7-0.7-3.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.047.611.30.00.00.00.00.0
Percentage of Revenues-0.1-0.3-0.1-0.0-0.2-0.0-0.0-0.2
Percentage of Revenues wec:Othernonutilityrevenues srt:ConsolidationEliminations us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, us-gaap:CorporateAndOther, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value0.00.50.80.40.41.30.81.51.52.32.81.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-9.8-2.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.10.00.00.10.10.10.10.10.20.1
Percentage of Revenues wec:Othernonutilityrevenues us-gaap:CorporateAndOther us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.0100.0100.0

wec:Othernonutilityrevenues, wec:NonUtilityEnergyInfrastructure, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value24231814171614121513107.99.37.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-278.2-174.40.00.0-208.5-116.30.00.00.00.00.00.00.00.0
Percentage of Revenues1.40.91.00.91.10.80.70.71.00.60.50.50.60.3
Percentage of Revenues wec:Othernonutilityrevenues wec:NonUtilityEnergyInfrastructure us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues

wec:Othernonutilityrevenues, us-gaap:TransferredOverTime, naics:ZZ811412, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value4.44.74.34.24.24.44.14.24.24.14.14.03.93.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-50.6-35.30.00.0-51.2-31.20.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.20.20.30.30.20.20.30.30.20.20.20.20.2
Percentage of Revenues wec:Othernonutilityrevenues us-gaap:TransferredOverTime naics:ZZ811412 us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

wec:Othernonutilityrevenues, us-gaap:TransferredOverTime, us-gaap:AlternativeEnergy, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1415107.47.39.37.04.95.96.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-166.7-118.80.00.0-89.0-66.00.00.00.00.0
Percentage of Revenues0.90.60.50.40.50.40.40.30.40.3
Percentage of Revenues wec:Othernonutilityrevenues us-gaap:TransferredOverTime us-gaap:AlternativeEnergy us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues

wec:Othernonutilityrevenues, wec:Distributedrenewablesolarprojectrevenues, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value0.00.30.70.40.41.30.81.51.62.32.81.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-8.5-2.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.00.00.00.10.10.10.10.10.20.1
Percentage of Revenues wec:Othernonutilityrevenues wec:Distributedrenewablesolarprojectrevenues us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.0100.0100.0

wec:Othernonutilityrevenues, wec:Other, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value-0.10.20.20.00.10.00.00.10.00.10.10.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-2.4-0.00.00.00.00.00.00.00.00.0
Percentage of Revenues-0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues wec:Othernonutilityrevenues wec:Other us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.0100.00.0

wec:Othernonutilityrevenues, wec:WePowerrevenues, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value5.85.85.85.85.85.56.36.46.36.46.36.46.26.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-66.7-43.60.00.0-70.7-39.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.30.20.30.40.40.30.30.40.40.30.30.40.40.3
Percentage of Revenues wec:Othernonutilityrevenues wec:WePowerrevenues us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, wec:TypesofOperatingRevenues

us-gaap:ElectricityUsRegulated, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value1083109510191212999103410381185102110611062121810841067
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-12450.6-8233.10.00.0-12190.2-7337.60.00.00.00.00.00.00.00.0
Percentage of Revenues64.640.752.773.564.549.153.373.764.344.751.174.164.846.7
Percentage of Revenues us-gaap:ElectricityUsRegulated us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NaturalGasUsRegulated, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value54615478614075251032864385524129610044035761210
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-6280.5-11636.80.00.0-6404.9-7324.10.00.00.00.00.00.00.00.0
Percentage of Revenues32.657.544.524.733.949.044.424.033.054.548.324.634.552.9
Percentage of Revenues us-gaap:NaturalGasUsRegulated us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:PublicUtilities, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value16292642188016201524206719031570154623582066162216602278
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-18731.0-19869.90.00.0-18595.1-14661.70.00.00.00.00.00.00.00.0
Percentage of Revenues97.298.297.298.298.598.097.797.797.399.299.598.799.399.6
Percentage of Revenues us-gaap:PublicUtilities us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Othernonutilityrevenues, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value2426201718191716171814131311
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-283.9-197.70.00.0-222.0-139.00.00.00.00.00.00.00.00.0
Percentage of Revenues1.51.01.11.11.20.90.91.01.10.80.70.80.80.5
Percentage of Revenues wec:Othernonutilityrevenues us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments, us-gaap:TimingOfTransferOfGoodOrService, wec:TypesofOperatingRevenues

wec:Illinois, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value266693366213254433365190232544432193273507
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-3058.6-5214.30.00.0-3103.7-3075.20.00.00.00.00.00.00.00.0
Percentage of Revenues15.925.818.912.916.420.618.711.814.622.920.811.816.422.2
Percentage of Revenues wec:Illinois us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:OtherStates, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value71230119476614412248681891454972176
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-819.5-1731.60.00.0-812.2-1022.70.00.00.00.00.00.00.00.0
Percentage of Revenues4.38.66.22.94.36.86.33.04.38.07.03.04.47.7
Percentage of Revenues wec:OtherStates us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:PublicUtility, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value16332646188316241528207119071574155023602068162816672269
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-18773.6-19895.50.00.0-18640.2-14690.10.00.00.00.00.00.00.00.0
Percentage of Revenues97.498.397.498.498.798.297.997.997.599.399.699.199.799.3
Percentage of Revenues wec:PublicUtility us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:Wisconsin, us-gaap:TransferredOverTime, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value12951722139713631207149314191336124916261491138513201585
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-14895.4-12949.60.00.0-14724.4-10592.20.00.00.00.00.00.00.00.0
Percentage of Revenues77.364.072.382.678.070.872.983.178.668.471.884.379.069.4
Percentage of Revenues wec:Wisconsin us-gaap:TransferredOverTime us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues

srt:ConsolidationEliminations, us-gaap:RevenueFromContractWithCustomer


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-9.9-12.1-15.7-9.1-12.2-15.4-13.4-15.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0147.6111.30.00.00.00.00.0
Percentage of Revenues-0.6-0.8-0.7-0.6-0.8-0.6-0.8-0.9
Percentage of Revenues srt:ConsolidationEliminations us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.0

us-gaap:CorporateAndOther, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value0.00.50.80.40.41.30.81.51.52.32.81.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.0-9.8-2.80.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.10.00.00.10.10.10.10.10.20.1
Percentage of Revenues us-gaap:CorporateAndOther us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.0100.0100.0

wec:NonUtilityEnergyInfrastructure, us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value3337302325302620252920171922
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-386.2-284.20.00.0-314.6-219.10.00.00.00.00.00.00.00.0
Percentage of Revenues2.01.41.61.41.71.51.41.31.61.21.01.11.21.0
Percentage of Revenues wec:NonUtilityEnergyInfrastructure us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax wec:TypesofOperatingRevenues

us-gaap:RevenueFromContractWithCustomer


Revenue
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
Value16542669190016381543208619211587156323762081163516732290
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-19014.9-20067.70.00.0-18817.1-14800.70.00.00.00.00.00.00.00.0
Percentage of Revenues98.799.298.399.299.699.098.798.798.3100.0100.299.5100.1100.2
Percentage of Revenues us-gaap:RevenueFromContractWithCustomer0.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value16762691193316511548210819471608159023772076164316722286205516571631230419631712160221941848169899113871225103310431695117810531012127510711039944
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ConsolidationItems

srt:ConsolidationEliminations


Revenuesus-gaap:
Period End2021-06-302021-03-312020-06-302020-03-31
Value-112.5-114.7-111.6-114.4
Percentage of Revenues-6.7-4.3-7.2-5.4
Percentage of Revenues-6.7-4.3-7.2-5.4
Percentage of Revenues srt:ConsolidationEliminations100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ConsolidationItems, wec:TypesofOperatingRevenues

us-gaap:IntersegmentElimination, wec:IntersegmentTransactions


Revenuesus-gaap:
Period End2021-06-302021-03-312020-06-302020-03-31
Value-112.5-114.7-111.6-114.4
Percentage of Revenues-6.7-4.3-7.2-5.4
Percentage of Revenues-6.7-4.3-7.2-5.4
Percentage of Revenues us-gaap:IntersegmentElimination wec:IntersegmentTransactions100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ProductOrService, us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues

us-gaap:PublicUtilities, wec:Illinois, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value275703391221261447379198242536426197268507389187
Percentage of Revenues16.426.120.213.416.921.219.512.315.322.620.612.016.022.219.011.3
Percentage of Revenues16.426.120.213.416.921.219.512.315.322.620.612.016.022.219.011.3
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilities, wec:OtherStates, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value7223312248661461234868185145507216913749
Percentage of Revenues4.38.76.32.94.36.96.33.04.37.87.03.14.37.46.73.0
Percentage of Revenues4.38.76.32.94.36.96.33.04.37.87.03.14.37.46.73.0
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PublicUtilities, wec:Wisconsin, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1307173114021366120614981421133912531633149113881325158915121401
Percentage of Revenues78.064.372.582.877.971.173.083.378.868.771.884.579.369.573.684.5
Percentage of Revenues78.064.372.582.877.971.173.083.378.868.771.884.579.369.573.684.5
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ProductOrService, wec:TypesofOperatingRevenues

us-gaap:PublicUtilities, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1655266819161636153420921923158615652355206316361665226620401638
Percentage of Revenues98.799.199.199.199.199.398.898.698.499.199.499.699.699.199.398.8
Percentage of Revenues98.799.199.199.199.199.398.898.698.499.199.499.699.699.199.398.8
Percentage of Revenues us-gaap:PublicUtilities wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value185188180187203186199184182177
Percentage of Revenues11.17.09.311.413.18.910.211.511.57.5
Percentage of Revenues11.17.09.311.413.18.910.211.511.57.5
Percentage of Revenues wec:TransmissionAffiliate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:StatementBusinessSegments

srt:ConsolidationEliminations


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-109.6-111.6-114.4-98.9-99.0-107.2-110.7-113.5
Percentage of Revenues-6.6-7.2-5.4-6.2-6.2-4.5-6.7-6.8
Percentage of Revenues-6.6-7.2-5.4-6.2-6.2-4.5-6.7-6.8
Percentage of Revenues srt:ConsolidationEliminations100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CorporateAndOther


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value0.10.10.20.60.90.50.51.30.91.71.82.43.11.42.05.63.22.93.04.04.41116270.50.30.40.30.30.30.30.40.30.30.30.30.3
Percentage of Revenues0.00.00.00.00.10.00.00.10.10.10.10.10.20.10.10.30.20.10.20.20.30.50.91.60.10.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues0.00.00.00.00.10.00.00.10.10.10.10.10.20.10.10.30.20.10.20.20.30.50.91.60.10.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:Illinois


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value275703391221261447379198242536426197268507
Percentage of Revenues16.426.120.213.416.921.219.512.315.322.620.612.016.022.2
Percentage of Revenues16.426.120.213.416.921.219.512.315.322.620.612.016.022.2
Percentage of Revenues wec:Illinois100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:NonUtilityEnergyInfrastructure


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-30
Value13313713012312512912511912312711811511711812136.26.2
Percentage of Revenues8.05.16.77.58.16.16.47.47.85.45.77.07.05.20.60.80.30.4
Percentage of Revenues8.05.16.77.58.16.16.47.47.85.45.77.07.05.20.60.80.30.4
Percentage of Revenues wec:NonUtilityEnergyInfrastructure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:OtherStates


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value72233122486614612348681851455072169
Percentage of Revenues4.38.76.32.94.36.96.33.04.37.87.03.14.37.4
Percentage of Revenues4.38.76.32.94.36.96.33.04.37.87.03.14.37.4
Percentage of Revenues wec:OtherStates100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:PublicUtility


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value16552668191616361534209219231586156523552063163616652266
Percentage of Revenues98.799.199.199.199.199.398.898.698.499.199.499.699.699.1
Percentage of Revenues98.799.199.199.199.199.398.898.698.499.199.499.699.699.1
Percentage of Revenues wec:PublicUtility100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:Wisconsin


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value13071731140213661206149814211339125316331491138813251589
Percentage of Revenues78.064.372.582.877.971.173.083.378.868.771.884.579.369.5
Percentage of Revenues78.064.372.582.877.971.173.083.378.868.771.884.579.369.5
Percentage of Revenues wec:Wisconsin100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:StatementBusinessSegments, wec:TypesofOperatingRevenues

us-gaap:CorporateAndOther, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.10.10.20.60.90.50.51.30.91.71.82.43.11.42.05.6
Percentage of Revenues0.00.00.00.00.10.00.00.10.10.10.10.10.20.10.10.3
Percentage of Revenues0.00.00.00.00.10.00.00.10.10.10.10.10.20.10.10.3
Percentage of Revenues us-gaap:CorporateAndOther wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IntersegmentElimination, wec:IntersegmentTransactions


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-109.6-111.6-114.4-102.3-98.9-99.0-107.2-107.0-110.7-113.5-99.3-113.1-111.6
Percentage of Revenues-6.6-7.2-5.4-5.3-6.2-6.2-4.5-5.2-6.7-6.8-4.3-5.5-6.7
Percentage of Revenues-6.6-7.2-5.4-5.3-6.2-6.2-4.5-5.2-6.7-6.8-4.3-5.5-6.7
Percentage of Revenues us-gaap:IntersegmentElimination wec:IntersegmentTransactions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:NonUtilityEnergyInfrastructure, wec:ExternalRevenues


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value21221713131523202420114.53.5181213
Percentage of Revenues1.30.90.90.80.90.71.21.31.50.90.50.30.20.80.60.8
Percentage of Revenues1.30.90.90.80.90.71.21.31.50.90.50.30.20.80.60.8
Percentage of Revenues wec:NonUtilityEnergyInfrastructure wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:NonUtilityEnergyInfrastructure, wec:IntersegmentTransactions


Revenuesus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value112114112109111114102989910710711011399113111
Percentage of Revenues6.74.35.86.67.25.45.36.26.24.55.26.76.84.35.56.7
Percentage of Revenues6.74.35.86.67.25.45.36.26.24.55.26.76.84.35.56.7
Percentage of Revenues wec:NonUtilityEnergyInfrastructure wec:IntersegmentTransactions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues wec:TypesofOperatingRevenues

wec:ExternalRevenues


Revenueswec:
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value167626911651154821081608159023771643167222861657
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues wec:ExternalRevenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-31
Value377943760037028354223504234832349513437733934337373347532562319373178531590310133055930016301232944329175291042935528769286141513515163147241461914800147691437214317142951428513834138871382113862132491307613188130591271812693127211269712617
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets dei:LegalEntity, us-gaap:ConsolidationItems

wec:WisconsinElectricPowerCompany, us-gaap:IntersegmentElimination


Assetsdei:
Period End2020-12-312019-12-312018-12-31
Value182418961968
Percentage of Assets4.95.45.9
Percentage of Assets4.95.45.9
Percentage of Assets wec:WisconsinElectricPowerCompany us-gaap:IntersegmentElimination100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidatedEntities

srt:ParentCompany


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-31
Value14434135261297212287
Percentage of Assets39.038.738.838.9
Percentage of Assets39.038.738.838.9
Percentage of Assets srt:ParentCompany100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-31
Value-3361.2-3344.5-3414.5
Percentage of Assets-9.1-9.6-10.2
Percentage of Assets-9.1-9.6-10.2
Percentage of Assets us-gaap:IntersegmentElimination100.0100.0100.0

us-gaap:Assets us-gaap:ProductOrService

us-gaap:PublicUtilities


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value3340732105310382944928440
Percentage of Assets90.291.992.793.294.4
Percentage of Assets90.291.992.793.294.4
Percentage of Assets us-gaap:PublicUtilities100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value74716932648361445714
Percentage of Assets20.219.819.419.519.0
Percentage of Assets20.219.819.419.519.0
Percentage of Assets us-gaap:PublicUtilities wec:Illinois100.0100.0100.0100.0100.0

us-gaap:PublicUtilities, wec:OtherStates


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1336123711471067995
Percentage of Assets3.63.53.43.43.3
Percentage of Assets3.63.53.43.43.3
Percentage of Assets us-gaap:PublicUtilities wec:OtherStates100.0100.0100.0100.0100.0

us-gaap:PublicUtilities, wec:Wisconsin


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2459923934234072223721730
Percentage of Assets66.468.569.970.472.1
Percentage of Assets66.468.569.970.472.1
Percentage of Assets us-gaap:PublicUtilities wec:Wisconsin100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value5555552154935467542753655328
Percentage of Assets14.714.714.815.415.515.415.2
Percentage of Assets14.714.714.815.415.515.415.2
Percentage of Assets wec:TransmissionAffiliate100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value762814959953778113248804719443146945075
Percentage of Assets2.12.32.93.02.63.932.232.031.033.938.9
Percentage of Assets2.12.32.93.02.63.932.232.031.033.938.9
Percentage of Assets us-gaap:CorporateAndOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:ElectricTransmissionSegment


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value176417231665159314761381
Percentage of Assets4.84.95.05.04.94.7
Percentage of Assets4.84.95.05.04.94.7
Percentage of Assets wec:ElectricTransmissionSegment100.0100.0100.0100.0100.0100.0

wec:NonUtilityEnergyInfrastructure


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value445536543227299227772779
Percentage of Assets12.010.59.69.59.29.5
Percentage of Assets12.010.59.69.59.29.5
Percentage of Assets wec:NonUtilityEnergyInfrastructure100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities us-gaap:AwardType

us-gaap:Liabilities

us-gaap:PerformanceShares


Liabilitiesus-gaap:
Period End2020-12-31
Value45
Percentage of Liabilities100.0
Percentage of Assets0.1
Percentage of Assets us-gaap:PerformanceShares0.0

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
Value3779437600370283542235042348323495134377339343373733475325623193731785315903101330559300163012329443291752910429355287692861415135151631472414619148001476914372143171429514285138341388713821138621324913076131881305912697
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
Value14434135261297212287
Percentage of LiabilitiesAndStockholdersEquity39.038.738.838.9
Percentage of Assets39.038.738.838.9
Percentage of Assets srt:ParentCompany100.0100.0100.0100.0

us-gaap:LiabilitiesAndStockholdersEquity us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value5555552154935467542753655328
Percentage of LiabilitiesAndStockholdersEquity14.714.714.815.415.515.415.2
Percentage of Assets14.714.714.815.415.515.415.2
Percentage of Assets wec:TransmissionAffiliate100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquity

srt:ParentCompany


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-31
Value104691011397889461
Percentage of StockholdersEquity100.0100.0100.0100.0
Percentage of Assets28.328.929.230.0
Percentage of Assets srt:ParentCompany72.574.875.577.0

us-gaap:StockholdersEquity us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value2317230422922270225822182214
Percentage of StockholdersEquity0.00.021.90.00.00.021.9
Percentage of Assets6.16.16.26.46.46.46.3
Percentage of Assets wec:TransmissionAffiliate41.741.741.741.541.641.341.6

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-6.8-4.1-2.62.92.94.60.30.30.30.1-0.1-0.5-0.9-1.3
Percentage of StockholdersEquity-0.1-0.0-0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets-0.0-0.0-0.00.00.00.00.00.00.00.0-0.0-0.0-0.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value414341864250427843094347300349500
Percentage of StockholdersEquity39.641.443.445.20.00.00.00.00.0
Percentage of Assets11.212.012.713.514.314.82.02.43.5
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value3.23.23.23.23.23.22.32.32.32.31.21.21.21.2
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value162110230.00.00.0
Percentage of StockholdersEquity1.61.10.20.00.00.0
Percentage of Assets0.40.30.10.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.0

us-gaap:Parent


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value10469101139788946189298654441942334135
Percentage of StockholdersEquity100.0100.0100.0100.00.00.00.00.00.0
Percentage of Assets28.328.929.230.029.629.529.128.728.9
Percentage of Assets us-gaap:Parent0.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value63295927553851764613429941173881363233623078280825842351
Percentage of StockholdersEquity60.558.656.654.70.00.00.00.00.00.00.00.00.00.0
Percentage of Assets17.117.016.516.415.314.627.226.325.424.323.622.120.50.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalEquity


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value10662102549842949189608685
Percentage of StockholdersEquity101.8101.4100.5100.30.00.0
Percentage of Assets28.829.329.430.029.729.6
Percentage of Assets wec:TotalEquity0.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


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
Value22782355208317271713184520931773183820082247183918101980221318231779185521681817176518962206218122761326153512741285154515511238127113131313108412361279142611321171145913311529
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.06.35.64.94.95.36.05.25.46.06.75.65.76.27.05.95.86.27.26.26.16.57.57.68.08.810.18.78.810.410.58.68.99.29.27.88.99.310.38.59.011.110.212.0

us-gaap:AssetsCurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Assets
Period End2020-12-312019-12-312018-12-312017-12-31
Value1707010888
Percentage of AssetsCurrent8.23.44.84.0
Percentage of Assets0.50.20.30.3
Percentage of Assets srt:ParentCompany1.20.50.80.7

us-gaap:AssetsCurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value92909292938284
Percentage of AssetsCurrent4.13.84.55.45.44.54.0
Percentage of Assets0.20.20.30.30.30.20.2
Percentage of Assets wec:TransmissionAffiliate1.71.61.71.71.71.51.6

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value3526241313153720373084142948381836453725323449222146561883327261821243513131814151023624111012203126
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.00.00.00.10.10.10.10.30.00.10.20.10.10.10.20.10.10.10.10.20.10.70.40.40.60.20.20.20.10.10.20.20.10.10.10.10.10.11.80.20.10.10.10.20.30.0

us-gaap:CashAndCashEquivalentsAtCarryingValue us-gaap:ConsolidatedEntities

srt:ParentCompany


Cash
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value4.00.5324.01.21.3
Percentage of CashAndCashEquivalentsAtCarryingValue16.11.338.810.33.22.6
Percentage of Assets0.00.00.10.00.00.0
Percentage of Assets srt:ParentCompany0.00.00.30.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-312014-12-31
Value99897261626582669089146405271583858737216861
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.20.20.20.20.20.20.20.30.30.40.10.20.20.20.10.20.20.20.60.4

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312017-12-312016-12-312015-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value118213691202911957117611761280135012411028667437352339404605406299327389285298297386349314344425344298
Percentage of AccountsReceivableNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.13.63.22.62.73.43.43.84.34.13.52.32.92.32.32.84.12.72.12.32.72.02.22.12.82.52.42.63.22.62.4

Other Assets Current

us-gaap:OtherAssetsCurrent

us-gaap:OtherAssetsCurrent


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value1104063596461688180507761493474434739974989595838121078785
Percentage of OtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.10.20.20.20.20.20.20.20.10.20.20.20.10.20.10.20.10.30.20.30.20.20.30.10.80.60.7

us-gaap:OtherAssetsCurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Other
Period End2020-12-312019-12-312018-12-312017-12-31
Value0.10.00.60.6
Percentage of OtherAssetsCurrent0.20.00.80.8
Percentage of Assets0.00.00.00.0
Percentage of Assets srt:ParentCompany0.00.00.00.0

Assets Noncurrent

us-gaap:AssetsNoncurrent

us-gaap:AssetsNoncurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value3551635245349453369433328329863285832604320953172831228307223012729804293772918928779281612795427148
Percentage of AssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets94.093.794.495.195.194.794.094.894.694.093.394.494.393.893.094.194.293.892.892.5

us-gaap:AssetsNoncurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Assets
Period End2020-12-312019-12-312018-12-312017-12-31
Value14264134561286412199
Percentage of AssetsNoncurrent40.841.041.241.5
Percentage of Assets38.538.538.438.6
Percentage of Assets srt:ParentCompany98.899.599.299.3

us-gaap:AssetsNoncurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value5462543154005375533452835244
Percentage of AssetsNoncurrent15.415.415.516.016.016.016.0
Percentage of Assets14.514.414.615.215.215.215.0
Percentage of Assets wec:TransmissionAffiliate98.398.498.398.398.398.598.4

Construction In Progress Gross

us-gaap:ConstructionInProgressGross us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

us-gaap:ConstructionInProgressGross

us-gaap:RegulatedOperation


Construction
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value683820707508320672170
Percentage of ConstructionInProgressGross100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.82.32.11.61.12.31.1
Percentage of Assets us-gaap:RegulatedOperation0.00.00.00.01.12.31.1

us-gaap:UnregulatedOperation


Construction
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value335248215710415021
Percentage of ConstructionInProgressGross49.03.011.731.032.722.312.8
Percentage of Assets0.90.10.20.50.30.50.1
Percentage of Assets us-gaap:UnregulatedOperation0.00.00.00.00.00.00.0

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment


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
Value96259481936493089157904288788807870585898515858985128819861885258433831282148141804980057919793078574560448544494384432342574202414040984036397239153855379737413687363936243431
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets25.525.225.326.326.126.025.425.625.725.525.426.426.727.727.327.527.627.727.327.727.627.527.027.627.530.129.630.230.029.228.829.228.928.728.328.728.227.927.428.228.227.627.727.0

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

us-gaap:RegulatedOperation


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value8465807375737021760973584044
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment90.490.988.981.592.692.990.2
Percentage of Assets22.923.122.622.225.325.126.7
Percentage of Assets us-gaap:RegulatedOperation0.00.00.00.025.425.527.3

us-gaap:UnregulatedOperation


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value899805731671604560440
Percentage of AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment9.69.18.67.87.47.19.8
Percentage of Assets2.42.32.22.12.01.92.9
Percentage of Assets us-gaap:UnregulatedOperation0.00.00.00.00.00.00.0

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
Value26266259942570724551241712379723620230352253522193220002166321078214662134720882205241999019915196121939819259191891878518529113161125711134110241094110906108051070410616105721043810340102351016099999821963996019015
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 Assets69.569.169.469.369.068.367.667.066.465.865.766.566.067.567.667.367.266.666.166.666.566.265.465.364.874.874.275.675.473.973.875.274.874.374.075.574.574.173.375.575.173.173.571.0

us-gaap:PropertyPlantAndEquipmentNet us-gaap:PublicUtilityRegulatedOrUnregulatedStatus

us-gaap:RegulatedOperation


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value2131519923186691806316895161188416
Percentage of PropertyPlantAndEquipmentNet82.984.384.984.684.884.074.8
Percentage of Assets57.657.055.857.256.154.955.5
Percentage of Assets us-gaap:RegulatedOperation0.00.00.00.056.555.856.8

us-gaap:UnregulatedOperation


Property
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value4391369733313283302030712841
Percentage of PropertyPlantAndEquipmentNet17.115.715.115.415.216.025.2
Percentage of Assets11.910.610.010.410.010.518.7
Percentage of Assets us-gaap:UnregulatedOperation0.00.00.00.00.00.00.0

Investments In Affiliates Subsidiaries Associates And Joint Ventures

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures

us-gaap:InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures


Investments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value17821773176417501744171717201720169616701665161315961598155314431380431424423416409402396390383378372362355349346341336330314
Percentage of InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.74.74.84.95.04.94.95.05.05.05.05.05.05.04.94.84.72.82.82.92.92.82.72.82.72.72.62.72.62.62.52.62.62.52.52.5

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
Value3052305230523052305230523052305230523052305230523052305230533053305330463046304630462999302333893386441441441441441441441441441441441441441441441441441441441
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 Assets8.18.18.28.68.78.88.78.99.09.09.19.49.69.69.79.810.010.110.110.310.410.310.311.811.82.92.93.03.03.03.03.13.13.13.13.23.23.23.23.33.43.43.43.5

us-gaap:Goodwill us-gaap:StatementBusinessSegments

wec:Illinois


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value7587587587587587587587587587587587587587587587587587587587587227310.00.0
Percentage of Goodwill24.924.924.924.924.924.924.924.924.924.924.924.924.924.924.824.824.824.924.924.924.124.20.00.0
Percentage of Assets2.02.02.02.12.22.22.22.22.22.22.32.32.42.42.42.42.52.52.62.62.52.50.00.0
Percentage of Assets wec:Illinois0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-31
Value6.66.66.66.66.66.66.66.66.66.66.66.66.66.67.37.30.00.0
Percentage of Goodwill0.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.20.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets wec:NonUtilityEnergyInfrastructure0.00.00.10.00.00.00.20.00.00.00.20.00.00.00.20.00.00.0

wec:OtherStates


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value1831831831831831831831831831831831831831831831831831831831831791820.00.0
Percentage of Goodwill6.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.06.00.00.0
Percentage of Assets0.50.50.50.50.50.50.50.50.50.50.50.60.60.60.60.60.60.60.60.60.60.60.00.0
Percentage of Assets wec:OtherStates0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:WisconsinSegment


Goodwillus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-31
Value21042104210421042104210421042104210421042104210421042104210421042109
Percentage of Goodwill68.968.968.968.968.968.968.968.968.968.968.968.968.968.968.969.169.8
Percentage of Assets5.65.65.75.96.06.06.06.16.26.26.36.56.66.66.77.07.2
Percentage of Assets wec:WisconsinSegment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Finite Lived Intangible Assets Net

us-gaap:FiniteLivedIntangibleAssetsNet dei:LegalEntity

us-gaap:FiniteLivedIntangibleAssetsNet

wec:WECInfrastructureLLC


Finite
Period End2021-06-302021-03-312020-12-312019-12-31
Value10093869.4
Percentage of FiniteLivedIntangibleAssetsNet100.0100.0100.0100.0
Percentage of Assets0.30.20.20.0
Percentage of Assets wec:WECInfrastructureLLC0.00.00.00.0

us-gaap:FiniteLivedIntangibleAssetsNet dei:LegalEntity, us-gaap:FiniteLivedIntangibleAssetsByMajorClass

wec:WECInfrastructureLLC, us-gaap:CustomerContracts


Finite
Period End2021-06-302021-03-312020-12-31
Value898376
Percentage of FiniteLivedIntangibleAssetsNet89.888.987.7
Percentage of Assets0.20.20.2
Percentage of Assets wec:WECInfrastructureLLC us-gaap:CustomerContracts0.00.00.0

wec:WECInfrastructureLLC, us-gaap:ServiceAgreements


Finite
Period End2021-06-302021-03-312020-12-312019-12-31
Value4.74.74.82.8
Percentage of FiniteLivedIntangibleAssetsNet4.75.05.529.8
Percentage of Assets0.00.00.00.0
Percentage of Assets wec:WECInfrastructureLLC us-gaap:ServiceAgreements0.00.00.00.0

wec:WECInfrastructureLLC, us-gaap:Swap


Finite
Period End2021-06-302021-03-312020-12-312019-12-31
Value5.55.75.96.6
Percentage of FiniteLivedIntangibleAssetsNet5.56.16.870.2
Percentage of Assets0.00.00.00.0
Percentage of Assets wec:WECInfrastructureLLC us-gaap:Swap0.00.00.00.0

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312019-01-01
Value204143444849
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.0

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssetsNoncurrent


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
Value1005937896877848853957796803802704749753757619584549527461418419379403511455317200321321328322186185179204179180184201210209215218171
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.72.52.42.52.42.42.72.32.42.42.12.32.42.42.01.91.81.81.51.41.41.31.41.81.62.11.32.22.22.22.21.31.31.31.41.31.31.31.51.61.61.61.71.4

us-gaap:OtherAssetsNoncurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Other
Period End2020-12-312019-12-312018-12-312017-12-31
Value15233147
Percentage of OtherAssetsNoncurrent1.82.44.57.7
Percentage of Assets0.00.10.10.2
Percentage of Assets srt:ParentCompany0.10.20.20.4

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
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
Value744656880751696597908769715674876690681592859743724582861663620584815777777291363315288435342296276257368277267239325274309269315290
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.01.72.42.12.01.72.62.22.12.02.62.12.11.92.72.42.41.92.92.32.12.02.82.72.71.92.42.12.02.92.32.11.91.82.62.01.91.72.32.12.42.02.42.3

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent us-gaap:ConsolidatedEntities

us-gaap:AccruedLiabilitiesCurrent

us-gaap:VariableInterestEntityPrimaryBeneficiary


Accrued
Period End2021-06-30
Value300000.0
Percentage of AccruedLiabilitiesCurrent100.0
Percentage of Assets0.0
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.0

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


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
Value3373371441482840348428473182281833622889333136023053360538693026278720542431202521372229270926662940156016681065980142414961291128012781443138714281171136410891143134017211894
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets8.99.911.28.09.98.29.18.29.98.610.011.19.611.312.29.89.16.88.16.97.37.79.29.310.310.311.07.26.79.610.19.08.98.910.110.010.38.59.88.28.710.213.214.9

us-gaap:LiabilitiesCurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Liabilities
Period End2020-12-312019-12-312018-12-312017-12-31
Value117412449691212
Percentage of LiabilitiesCurrent28.339.129.131.3
Percentage of Assets3.23.62.93.8
Percentage of Assets srt:ParentCompany8.19.27.59.9

us-gaap:LiabilitiesCurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value427420310349434526502
Percentage of LiabilitiesCurrent12.711.37.512.312.518.515.8
Percentage of Assets1.11.10.81.01.21.51.4
Percentage of Assets wec:TransmissionAffiliate7.77.65.76.48.09.89.4

Long Term Debt Current

us-gaap:LongTermDebtCurrent

us-gaap:LongTermDebtCurrent


Long
Period End2020-12-312019-12-312018-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value7776863608995152157606608426424474534334237141441341238133433323130479473295
Percentage of LongTermDebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.12.01.10.30.30.50.52.12.12.82.80.30.32.32.32.62.92.92.92.82.40.20.20.20.23.63.62.3

us-gaap:LongTermDebtCurrent us-gaap:ConsolidatedEntities

us-gaap:VariableInterestEntityPrimaryBeneficiary


Long
Period End2021-06-30
Value4.1
Percentage of LongTermDebtCurrent0.0
Percentage of Assets0.0
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.0

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OtherCurrentLiabilities


Operating
Period End2020-12-31
Value3400000.0
Percentage of OperatingLeaseLiabilityCurrent100.0
Percentage of Assets0.0
Percentage of Assets us-gaap:OtherCurrentLiabilities0.0

Other Liabilities Current

us-gaap:OtherLiabilitiesCurrent

us-gaap:OtherLiabilitiesCurrent


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
Value711568530547519443550503457578464393364747553442440421388240358375471466592219168155166150177170178219167173177262230286245294259259
Percentage of OtherLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.91.51.41.51.51.31.61.51.31.71.41.21.12.41.81.41.41.41.30.81.21.31.61.62.11.51.11.11.11.01.21.21.21.51.21.31.31.91.72.21.92.22.02.0

us-gaap:OtherLiabilitiesCurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Other
Period End2020-12-312019-12-312018-12-312017-12-31
Value1917148.9
Percentage of OtherLiabilitiesCurrent3.73.23.01.6
Percentage of Assets0.10.10.00.0
Percentage of Assets srt:ParentCompany0.10.10.10.1

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value2339022918222172202221064214992151421372204242073520301191171912818481182291876118589188061873117961
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets61.961.060.062.260.161.761.662.260.261.560.658.759.958.157.760.560.862.762.261.2

us-gaap:LiabilitiesNoncurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Liabilities
Period End2020-12-312019-12-312018-12-312017-12-31
Value2789216822141613
Percentage of LiabilitiesNoncurrent12.610.110.98.9
Percentage of Assets7.56.26.65.1
Percentage of Assets srt:ParentCompany19.316.017.113.1

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2020-12-312019-12-312018-12-312017-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value124501185899948746455246264772454142884049
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets33.633.929.927.730.031.333.432.832.831.9

us-gaap:LongTermDebt us-gaap:ConsolidatedEntities, us-gaap:FairValueByMeasurementBasis

srt:ParentCompany, us-gaap:CarryingReportedAmountFairValueDisclosure


Long
Period End2020-12-312019-12-312018-12-312017-12-31
Value2754254121901892
Percentage of LongTermDebt22.121.421.921.6
Percentage of Assets7.47.36.56.0
Percentage of Assets srt:ParentCompany us-gaap:CarryingReportedAmountFairValueDisclosure0.00.00.00.0

srt:ParentCompany, us-gaap:EstimateOfFairValueFairValueDisclosure


Long
Period End2020-12-312019-12-312018-12-312017-12-31
Value2836261921321941
Percentage of LongTermDebt22.822.121.322.2
Percentage of Assets7.77.56.46.1
Percentage of Assets srt:ParentCompany us-gaap:EstimateOfFairValueFairValueDisclosure0.00.00.00.0

us-gaap:LongTermDebt us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value131271304112450121841155011844118581154110666106701033594649477954995619467947992729285913989529055922193009118454345524554456546174626465947124772
Percentage of LongTermDebt0.00.0100.00.00.00.0100.00.00.00.0103.40.00.00.0109.30.00.00.00.00.00.00.00.00.00.00.0100.00.00.00.0100.00.00.0100.0
Percentage of Assets34.734.733.634.433.034.033.933.631.431.630.929.129.730.030.330.531.030.930.831.030.731.131.432.331.930.030.030.931.231.231.332.432.933.4
Percentage of Assets us-gaap:CarryingReportedAmountFairValueDisclosure0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:EstimateOfFairValueFairValueDisclosure


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value14673141391434314007132781292013035127511154311257105549762982710054103411013510128973098181024899849790968193869181515751264979499549544911495150975447
Percentage of LongTermDebt0.00.0115.20.00.00.0109.90.00.00.0105.60.00.00.0118.20.00.00.00.00.00.00.00.00.00.00.0112.60.00.00.0106.20.00.0114.1
Percentage of Assets38.837.638.739.537.937.137.337.134.033.431.530.030.831.632.732.733.132.432.634.834.233.633.032.632.134.133.833.834.233.533.334.535.638.1
Percentage of Assets us-gaap:EstimateOfFairValueFairValueDisclosure0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent

us-gaap:LongTermDebtNoncurrent


Long
Period End2020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1167211171108979921103269994911992098617874687858799914391589088890289559124872785474169418645694587434843634370438344414453424042974602461446184334433939323875
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets31.532.031.729.230.629.928.028.827.127.728.328.830.530.430.930.530.831.130.329.927.527.631.031.429.429.530.430.631.131.230.730.933.333.334.933.132.930.130.5

us-gaap:LongTermDebtNoncurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Long
Period End2020-12-312019-12-312018-12-312017-12-31
Value2754214121901592
Percentage of LongTermDebtNoncurrent23.619.221.918.2
Percentage of Assets7.46.16.55.0
Percentage of Assets srt:ParentCompany19.115.816.913.0

us-gaap:VariableInterestEntityPrimaryBeneficiary


Long
Period End2021-06-30
Value111
Percentage of LongTermDebtNoncurrent0.0
Percentage of Assets0.3
Percentage of Assets us-gaap:VariableInterestEntityPrimaryBeneficiary0.0

us-gaap:LongTermDebtNoncurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value2412241225122512241223132312
Percentage of LongTermDebtNoncurrent0.00.021.50.00.00.020.7
Percentage of Assets6.46.46.87.16.96.66.6
Percentage of Assets wec:TransmissionAffiliate43.443.745.745.944.543.143.4

Long Term Debt And Capital Lease Obligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value126951231711728116521072111194112119994874691589124418643634453461439323875
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets33.632.831.732.930.632.132.129.927.730.431.127.629.531.233.330.130.5

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value4269421440593974394538703769
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.311.211.011.211.311.110.8

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent


Pension
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
Value314319327320322324326411414418422489490523397463451458498545541541543427428203203168169169173214225233244149251221222100233227353318
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.80.90.90.90.90.90.91.21.21.21.31.51.51.61.31.51.51.51.71.91.91.91.91.51.51.31.31.11.21.11.21.51.61.61.71.11.81.61.60.81.81.72.72.5

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Pension
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2220475774
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent6.96.311.214.515.0
Percentage of Assets0.10.10.10.20.2
Percentage of Assets us-gaap:OtherPostretirementBenefitPlansDefinedBenefit0.00.00.00.00.0

us-gaap:PensionPlansDefinedBenefit


Pension
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value304305375339424
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent93.193.788.885.585.0
Percentage of Assets0.80.91.11.11.4
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.00.0

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent


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
Value1256123612291128109311061128111611061109110812331203119112061194117111611164116711321067107110341626294303273275280295289288276285298302300314336333359290283
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.33.33.33.23.13.23.23.23.33.33.33.83.83.73.83.93.83.93.94.03.93.73.73.65.71.92.01.91.91.92.02.02.01.92.02.22.22.22.32.52.62.72.22.2

us-gaap:OtherLiabilitiesNoncurrent us-gaap:ConsolidatedEntities

srt:ParentCompany


Other
Period End2020-12-312019-12-312018-12-312017-12-31
Value34262421
Percentage of OtherLiabilitiesNoncurrent2.82.42.21.8
Percentage of Assets0.10.10.10.1
Percentage of Assets srt:ParentCompany0.20.20.20.2

us-gaap:OtherLiabilitiesNoncurrent us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value397385378335321307298
Percentage of OtherLiabilitiesNoncurrent31.631.130.829.729.427.826.5
Percentage of Assets1.11.01.00.90.90.90.9
Percentage of Assets wec:TransmissionAffiliate7.27.06.96.15.95.75.6

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OtherNoncurrentLiabilities


Operating
Period End2020-12-31
Value32
Percentage of OperatingLeaseLiabilityNoncurrent100.0
Percentage of Assets0.1
Percentage of Assets us-gaap:OtherNoncurrentLiabilities0.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo


Lessee
Period End2020-12-31
Value4400000.0
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
Value4500000.0
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
Value4300000.0
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
Value3800000.0
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
Value24
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets0.1

Operating Lease Liability

us-gaap:OperatingLeaseLiability us-gaap:BalanceSheetLocation

us-gaap:OperatingLeaseLiability

wec:TotalLiabilities


Operating
Period End2020-12-31
Value35
Percentage of OperatingLeaseLiability100.0
Percentage of Assets0.1
Percentage of Assets wec:TotalLiabilities0.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue


Lessee
Period End2020-12-31
Value46
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
Value10
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets0.0

Stockholders Equity

us-gaap:StockholdersEquity us-gaap:ConsolidatedEntities

us-gaap:StockholdersEquity

srt:ParentCompany


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-31
Value104691011397889461
Percentage of StockholdersEquity100.0100.0100.0100.0
Percentage of Assets28.328.929.230.0
Percentage of Assets srt:ParentCompany72.574.875.577.0

us-gaap:StockholdersEquity us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value2317230422922270225822182214
Percentage of StockholdersEquity0.00.021.90.00.00.021.9
Percentage of Assets6.16.16.26.46.46.46.3
Percentage of Assets wec:TransmissionAffiliate41.741.741.741.541.641.341.6

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-6.8-4.1-2.62.92.94.60.30.30.30.1-0.1-0.5-0.9-1.3
Percentage of StockholdersEquity-0.1-0.0-0.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets-0.0-0.0-0.00.00.00.00.00.00.00.0-0.0-0.0-0.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value414341864250427843094347300349500
Percentage of StockholdersEquity39.641.443.445.20.00.00.00.00.0
Percentage of Assets11.212.012.713.514.314.82.02.43.5
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value3.23.23.23.23.23.22.32.32.32.31.21.21.21.2
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value162110230.00.00.0
Percentage of StockholdersEquity1.61.10.20.00.00.0
Percentage of Assets0.40.30.10.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.0

us-gaap:Parent


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value10469101139788946189298654441942334135
Percentage of StockholdersEquity100.0100.0100.0100.00.00.00.00.00.0
Percentage of Assets28.328.929.230.029.629.529.128.728.9
Percentage of Assets us-gaap:Parent0.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value63295927553851764613429941173881363233623078280825842351
Percentage of StockholdersEquity60.558.656.654.70.00.00.00.00.00.00.00.00.00.0
Percentage of Assets17.117.016.516.415.314.627.226.325.424.323.622.120.50.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

wec:TotalEquity


Stockholders
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value10662102549842949189608685
Percentage of StockholdersEquity101.8101.4100.5100.30.00.0
Percentage of Assets28.829.329.430.029.729.6
Percentage of Assets wec:TotalEquity0.00.00.00.00.00.0

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value110301096710662105591049210484102541018610148101129842984297569698949192258960
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.229.228.829.829.930.129.329.629.930.029.430.230.530.530.029.729.7

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value-4.6-5.7-6.8-6.4-7.3-7.1-4.1-7.1-6.6-4.0-2.62.42.54.62.92.42.9
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-0.0-0.1-0.1-0.1-0.1-0.1-0.0-0.1-0.1-0.0-0.00.00.00.00.00.00.0
Percentage of Assets-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value41444143414341634165416741864185419742134250426142714267427842814309
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest37.637.838.939.439.739.740.841.141.441.743.243.343.844.045.146.448.1
Percentage of Assets11.011.011.211.811.912.012.012.212.412.512.713.113.413.413.513.814.3
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NoncontrollingInterest


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value16917016278781101101051019723370.00.00.00.00.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest1.51.61.50.70.71.11.11.01.01.00.20.40.00.00.00.00.0
Percentage of Assets0.40.50.40.20.20.30.30.30.30.30.10.10.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Parent


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value10830107671046910450103831034410113100511001699849788977597259667946191958929
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest98.298.298.299.099.098.798.698.798.798.799.599.399.799.799.799.799.7
Percentage of Assets28.728.628.329.529.629.728.929.229.529.629.230.030.530.430.029.629.6
Percentage of Assets us-gaap:Parent0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value66886626632962906222618059275869582157725538550854495392517649084613
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest60.660.459.459.659.359.057.857.657.457.156.356.055.955.654.553.251.5
Percentage of Assets17.717.617.117.817.817.717.017.117.217.116.516.917.117.016.415.815.3
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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
Value3.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.23.284564510441943984367432242334198419542034135414740814051396339403947390438023566
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 Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.029.629.829.129.929.929.228.729.229.329.428.930.029.429.328.629.730.229.629.128.1

Additional Paid In Capital Common Stock

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AdditionalPaidInCapitalCommonStock


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value41444143414341634165416741864250427843094347300
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets11.011.011.211.811.912.012.012.713.514.314.82.0

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-31
Value6688662663296290622261805927586958215772553855085449539251764908485748224613457545154489429942644117
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets17.717.617.117.817.817.717.017.117.217.116.516.917.117.016.415.815.916.115.315.515.515.414.614.827.2

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-31
Value-4.6-5.7-6.8-6.4-7.3-7.1-4.1-7.1-6.6-4.0-2.62.42.54.62.92.42.52.72.93.74.44.34.6110.3
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Minority Interest Decrease From Distributions To Noncontrolling Interest Holders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-30
Value900000.0400000.0600000.0700000.0500000.0600000.0900000.0
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.0

us-gaap:MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Minority
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-30
Value900000.0400000.0600000.0700000.0500000.0600000.0900000.0
Percentage of MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.0
Percentage of Assets us-gaap:NoncontrollingInterest0.00.00.00.00.00.00.0

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
Value831395246570689690504549555735437494619894331478553714381497528695221357386329163313336385180368351330181383268340165179257391156230120303
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 Revenues49.614.712.734.544.532.725.934.234.930.921.130.137.039.116.228.933.931.019.529.133.031.712.021.039.023.813.330.332.222.715.335.034.725.916.936.928.40.00.00.00.00.00.00.00.00.0

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-533.3-541.3-1243.7-556.9-543.2-463.0-760.4-668.1-459.8-606.6-664.4-723.2-561.0-435.8-702.1-528.1-698.3-325.6-512.6-392.5-260.7-188.4-326.7-416.7-1522.9-156.3-227.9-216.0-173.8-139.1-201.0-208.2-191.3-145.3-238.2-178.8-182.2-130.4-242.2-282.8-223.1-144.4-223.5-134.7-104.2-171.1
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 Revenues-31.8-20.1-64.3-33.7-35.1-22.0-39.0-41.5-28.9-25.5-32.0-44.0-33.5-19.1-34.2-31.9-42.8-14.1-26.1-22.9-16.3-8.6-17.7-24.5-153.6-11.3-18.6-20.9-16.7-8.2-17.1-19.8-18.9-11.4-22.2-17.2-19.30.00.00.00.00.00.00.00.00.0

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
Value-287.61631008-14.4-149.2-244.127194-94.1-186.1333216-78.1-445.137531135-380.859-112.4-270.1-522.6251-132.81285-170.138-42.0-156.6-244.427-163.1-163.6-195.979-205.0-91.0-206.175108-259.9-35.180-94.6-17.4-140.7
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 Revenues-17.26.152.2-0.9-9.6-11.613.95.9-5.9-7.816.013.2-4.7-19.518.31.98.3-16.53.0-6.6-16.9-23.813.6-7.8129.7-12.33.1-4.1-15.0-14.42.4-15.5-16.2-15.47.4-19.7-9.60.00.00.00.00.00.00.00.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value101711-1.2-3.3-16.615-24.11.6-57.0105-11.8-19.71320-19.8-15.10.7
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.60.60.6-0.1-0.2-0.80.8-1.50.1-2.45.1-0.7-1.20.61.0-1.2-0.90.0

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value266261249245242239236233229226217212206208205201197194193191190187179176105105103103101100999696959491908784828281777776
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepreciationDepletionAndAmortization us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination


Depreciation
Period End2021-06-302021-03-312020-06-302020-03-31
Value-14.7-14.3-12.8-12.2
Percentage of DepreciationDepletionAndAmortization-5.5-5.5-5.3-5.1

us-gaap:DepreciationDepletionAndAmortization us-gaap:ProductOrService

us-gaap:PublicUtilities


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value243238231228224220211208204202190186180182179176
Percentage of DepreciationDepletionAndAmortization91.491.192.893.192.692.389.489.089.089.287.787.787.587.587.487.8

us-gaap:DepreciationDepletionAndAmortization us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value54525049484746454544444341404038
Percentage of DepreciationDepletionAndAmortization20.320.220.320.420.019.919.519.519.619.720.520.220.219.619.519.3

us-gaap:PublicUtilities, wec:OtherStates


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value9.49.28.98.58.37.87.56.86.76.56.66.44.56.66.46.3
Percentage of DepreciationDepletionAndAmortization3.53.53.63.53.43.33.22.92.92.93.03.02.23.23.13.1

us-gaap:PublicUtilities, wec:Wisconsin


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value179176171169167165157155152151139137134135132131
Percentage of DepreciationDepletionAndAmortization67.567.468.969.369.169.266.766.666.566.764.264.565.164.864.765.4

us-gaap:DepreciationDepletionAndAmortization us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value6.46.66.16.56.46.15.96.06.06.46.87.17.57.77.66.36.45.69.21112105.66.10.10.20.20.00.40.10.20.20.20.20.10.30.20.10.20.20.1
Percentage of DepreciationDepletionAndAmortization2.42.52.42.72.62.62.52.62.62.83.13.33.63.73.73.13.22.94.85.96.35.43.13.50.10.20.20.00.40.10.20.20.20.20.10.30.20.10.20.20.1

us-gaap:IntersegmentElimination


Depreciation
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value-14.1-12.8-12.2-4.0-3.6-3.6-4.60.00.00.00.00.00.00.00.00.00.00.00.00.1-0.10.00.0
Percentage of DepreciationDepletionAndAmortization-5.8-5.3-5.1-1.7-1.5-1.6-2.00.00.00.00.00.00.00.00.00.00.00.00.00.1-0.10.00.0

wec:NonUtilityEnergyInfrastructure


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3131252424242323222220191818181817171717
Percentage of DepreciationDepletionAndAmortization11.811.910.210.010.110.29.810.010.010.09.29.08.98.88.99.08.89.08.98.9

Increase Decrease In Accounts Payable

us-gaap:IncreaseDecreaseInAccountsPayable

us-gaap:IncreaseDecreaseInAccountsPayable


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
Value62-181.51179.461-250.119330-18.4-204.31811385-170.91192.898-212.71291711-123.746-83.398-71.35124-147.394442717-104.51003.722-82.353-3.19.7-48.461-10.06.3-36.1
Percentage of IncreaseDecreaseInAccountsPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Increase Decrease In Inventories

us-gaap:IncreaseDecreaseInInventories

us-gaap:IncreaseDecreaseInInventories


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
Value99-175.1-44.810576-158.7-43.4131131-218.3-60.214190-163.0-133.416292-170.5-66.215923-217.2-32.017338-110.9217569-94.5-38.24951-93.9187.123-70.4142854-94.7-43.23254-42.3
Percentage of IncreaseDecreaseInInventories100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value831395246570689690504549555735437494619894331478553714381497528695221357386329163313336385180368351330181383268340165179257391156230120303
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 Revenues49.614.712.734.544.532.725.934.234.930.921.130.137.039.116.228.933.931.019.529.133.031.712.021.039.023.813.330.332.222.715.335.034.725.916.936.928.40.00.00.00.00.00.00.00.00.0

Net Income Loss

us-gaap:NetIncomeLoss us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

us-gaap:NetIncomeLoss

wec:TransmissionAffiliate


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value65656466806380616058
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues3.92.43.44.05.23.04.13.83.82.5
Percentage of Revenues wec:TransmissionAffiliate35.234.535.935.539.533.840.333.332.932.9

Profit Loss

us-gaap:ProfitLoss

us-gaap:ProfitLoss


Profit
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value275510239267242452244234235420206433801951211261332071441371191769815611917211612910917012511288
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues16.419.012.416.215.621.512.514.614.817.79.921.18.214.19.912.212.712.212.213.111.813.89.215.012.60.00.00.00.00.00.00.00.0

us-gaap:ProfitLoss us-gaap:ProductOrService

us-gaap:PublicUtilities


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value192393165380
Percentage of ProfitLoss70.077.168.284.1
Percentage of Revenues11.514.610.718.0
Percentage of Revenues us-gaap:PublicUtilities0.00.00.00.0

us-gaap:ProfitLoss us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value4311232107
Percentage of ProfitLoss15.822.013.323.7
Percentage of Revenues2.64.22.15.1
Percentage of Revenues us-gaap:PublicUtilities wec:Illinois0.00.00.00.0

us-gaap:PublicUtilities, wec:OtherStates


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value2.5242.826
Percentage of ProfitLoss0.94.81.25.8
Percentage of Revenues0.10.90.21.2
Percentage of Revenues us-gaap:PublicUtilities wec:OtherStates0.00.00.00.0

us-gaap:PublicUtilities, wec:Wisconsin


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value146256130247
Percentage of ProfitLoss53.250.353.754.6
Percentage of Revenues8.89.58.411.7
Percentage of Revenues us-gaap:PublicUtilities wec:Wisconsin0.00.00.00.0

us-gaap:ProfitLoss us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Profit
Period End2021-06-302021-03-312020-06-302020-03-312015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value-12.417-21.4-18.38219712112613220714413711817698156119172115129109
Percentage of ProfitLoss-4.53.4-8.8-4.0101.5100.699.9100.099.9100.0100.099.999.9100.099.3100.0100.0100.399.999.9100.0
Percentage of Revenues-0.70.7-1.4-0.98.314.29.912.212.712.212.213.011.713.89.215.012.60.00.00.00.0
Percentage of Revenues us-gaap:CorporateAndOther-12400.017600.0-2377.8-3660.016420.065666.730325.042100.044300.069166.748100.034350.039633.358866.732700.052033.339766.70.00.00.00.0

wec:ElectricTransmissionSegment


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value27283325
Percentage of ProfitLoss9.85.513.85.5
Percentage of Revenues1.61.02.21.2
Percentage of Revenues wec:ElectricTransmissionSegment0.00.00.00.0

wec:NonUtilityEnergyInfrastructure


Profit
Period End2021-06-302021-03-312020-06-302020-03-31
Value68716565
Percentage of ProfitLoss24.714.026.814.4
Percentage of Revenues4.12.64.23.1
Percentage of Revenues wec:NonUtilityEnergyInfrastructure51.151.851.950.4

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-533.3-541.3-1243.7-556.9-543.2-463.0-760.4-668.1-459.8-606.6-664.4-723.2-561.0-435.8-702.1-528.1-698.3-325.6-512.6-392.5-260.7-188.4-326.7-416.7-1522.9-156.3-227.9-216.0-173.8-139.1-201.0-208.2-191.3-145.3-238.2-178.8-182.2-130.4-242.2-282.8-223.1-144.4-223.5-134.7-104.2-171.1
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 Revenues-31.8-20.1-64.3-33.7-35.1-22.0-39.0-41.5-28.9-25.5-32.0-44.0-33.5-19.1-34.2-31.9-42.8-14.1-26.1-22.9-16.3-8.6-17.7-24.5-153.6-11.3-18.6-20.9-16.7-8.2-17.1-19.8-18.9-11.4-22.2-17.2-19.30.00.00.00.00.00.00.00.00.0

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value53947012555815414961017656496358926575475439650519460329423381306312501408207149223207176129189190173133229163171
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value-287.61631008-14.4-149.2-244.127194-94.1-186.1333216-78.1-445.137531135-380.859-112.4-270.1-522.6251-132.81285-170.138-42.0-156.6-244.427-163.1-163.6-195.979-205.0-91.0-206.175108-259.9-35.180-94.6-17.4-140.7
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 Revenues-17.26.152.2-0.9-9.6-11.613.95.9-5.9-7.816.013.2-4.7-19.518.31.98.3-16.53.0-6.6-16.9-23.813.6-7.8129.7-12.33.1-4.1-15.0-14.42.4-15.5-16.2-15.47.4-19.7-9.60.00.00.00.00.00.00.00.00.0

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:ProceedsFromIssuanceOfLongTermDebt


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-302015-12-312015-09-302014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312011-01-312010-12-312010-09-302010-06-302010-03-31
Value41860015637001100.05759700.035011400.06000.02250.02002005002000.00.02500.00.01.02500.02510.00.00.00.03000.04204200.00.00.0530
Percentage of ProceedsFromIssuanceOfLongTermDebt100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.00.0100.00.0100.00.0100.0100.0100.0100.00.00.0100.00.00.0100.0100.00.0100.00.00.00.00.0100.00.0100.0100.00.00.00.0100.0

Repayments Of Long Term Debt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt


Repayments
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
Value3261412846440414254884.0132581366812127122.6125211102139502152.39.32.3103028.933533028.52.08.32.08.01.97.84515.01.8261.8261
Percentage of RepaymentsOfLongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments 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
Value21321319919919919918618618618617417417417416416416416415615615615614412095958888878886867777686969696060606046464646
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
Value4.76.6426.49.9401.931357030224.015102019202.41134598.6348.62339264.75235526966482847295883262428593731
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

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:EffectiveIncomeTaxRateContinuingOperations


Effective
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value16.412.814.90.1820.1660.0460.0610.1340.0680.1810.184
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:EmployeeStockOption


Share
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value64.1354.9848.8643.1138.9533.4733.1632.3232.0429.9929.2728.8728.8226.8426.5826.5326.3423.86
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod us-gaap:AwardType

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod

us-gaap:PerformanceShares


Share
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312015-01-312014-12-312014-09-302014-06-302014-03-312014-01-312013-12-312013-09-302013-06-302013-03-312013-01-312012-09-302012-06-302012-03-312012-01-312011-09-302011-01-312010-01-31
Value0152380.01760.011250.0140460.0148040.0000217560.0000237650.0-92.0013892.0283500.0000195360.0195360.0000233740.0233740.0000239120.0239120.000346570.0346570.00435690.0555830.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod0.0100.0100.0100.0100.0100.00.00.00.0100.00.00.00.0100.0100.00.0100.0100.00.00.00.0100.0100.00.00.00.0100.0100.00.00.00.0100.0100.00.00.0100.0100.00.0100.0100.0

us-gaap:RestrictedStock


Share
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312015-01-312014-12-312014-09-302014-06-302014-03-312014-01-312013-12-312013-09-302013-06-302013-03-312013-01-312012-12-312012-09-302012-06-30
Value069681.0406.06927.084540.073571.0000156340.000082622.0006044.0140900.0082943.0060164.060164.000071504.071504.000074290.074290.0000
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod0.045.723.161.660.249.70.00.00.071.90.00.00.034.8-0.00.043.549.70.00.00.030.830.80.00.00.030.630.60.00.00.031.131.10.00.00.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value405937693388299951464622336631782915254617991607
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Net

us-gaap:DeferredTaxAssetsNet

us-gaap:DeferredTaxAssetsNet


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value899884962137611291052702854844872645589
Percentage of DeferredTaxAssetsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Unrecognized Tax Benefits

us-gaap:UnrecognizedTaxBenefits

us-gaap:UnrecognizedTaxBenefits


Unrecognized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-31
Value11172017149.57.28.41111293537
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Assets Valuation Allowance

us-gaap:DeferredTaxAssetsValuationAllowance

us-gaap:DeferredTaxAssetsValuationAllowance


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312010-12-312009-12-31
Value2.32.3111515170.01615
Percentage of DeferredTaxAssetsValuationAllowance100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:AdjustmentForAmortization

us-gaap:AdjustmentForAmortization


Adjustment
Period End2021-06-30
Value1900000.0
Percentage of AdjustmentForAmortization100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value9.21311121415
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries us-gaap:ProductOrService

us-gaap:PublicUtilities


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value9.21311121415
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableRecoveries us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value4.73.03.94.43.84.9
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries51.122.633.135.226.631.0

us-gaap:PublicUtilities, wec:OtherStates


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.30.40.30.30.40.4
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries3.33.02.52.42.82.5

us-gaap:PublicUtilities, wec:Wisconsin


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value4.29.97.67.81010
Percentage of AllowanceForDoubtfulAccountsReceivableRecoveries45.774.464.462.470.666.5

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value212117253652
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs us-gaap:ProductOrService

us-gaap:PublicUtilities


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value212117253652
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value4.02.83.510.01731
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs19.012.819.839.448.960.1

us-gaap:PublicUtilities, wec:OtherStates


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value0.60.50.50.90.71.3
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs2.82.32.83.51.92.5

us-gaap:PublicUtilities, wec:Wisconsin


Allowance
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value161813141819
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs78.284.977.457.149.237.5

us-gaap:BusinessCombinationConsiderationTransferred1 dei:LegalEntity, us-gaap:BusinessAcquisition

us-gaap:BusinessCombinationConsiderationTransferred1

wec:WECInfrastructureLLC, wec:BloomingGroveWindEnergyCenter


Business
Period End2020-12-31
Value364
Percentage of BusinessCombinationConsiderationTransferred1100.0

wec:WECInfrastructureLLC, wec:TatankaRidgeWind


Business
Period End2020-12-31
Value239
Percentage of BusinessCombinationConsiderationTransferred165.8

us-gaap:CapitalExpendituresIncurredButNotYetPaid

us-gaap:CapitalExpendituresIncurredButNotYetPaid


Capital
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
Value3097-24.74034102-2.8256274-6.0-5.52.574-3.5173911657-0.92390-2.01751.91.6-3.1
Percentage of CapitalExpendituresIncurredButNotYetPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAcquiredFromAcquisition us-gaap:BusinessAcquisition

us-gaap:CashAcquiredFromAcquisition

wec:BloomingGroveWindEnergyCenter


Cash
Period End2020-12-31
Value24
Percentage of CashAcquiredFromAcquisition100.0

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:CommonStockDividendsPerShareDeclared


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-012015-07-062015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value0.67750.67750.63250.63250.63250.63250.590.590.590.590.55250.55250.55250.55250.520.520.520.520.4950.4950.4950.4950.450.457500.45750.86290.42250.390.390.390.390.38750.38250.340.340.30.30.30.260.260.260.20.20.2
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockDividendsPerShareDeclared us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


Common
Period End2021-09-302021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-012018-09-302018-04-192018-03-312017-10-192017-07-202017-04-202017-01-312016-10-20
Value0.67750.67750.67750.63250.63250.63250.63250.590.590.590.590.55250.55250.55250.55250.520.520.520.520.495
Percentage of CommonStockDividendsPerShareDeclared0.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.00.00.00.00.00.0

us-gaap:ContractWithCustomerLiabilityRevenueRecognized wec:TypesofNonUtilityOperatingRevenues, wec:TypesofOperatingRevenues

us-gaap:ContractWithCustomerLiabilityRevenueRecognized

wec:WePowerrevenues, us-gaap:RevenueFromContractWithCustomer


Contract
Period End2021-03-312020-09-302020-03-312019-09-30
Value5.85.85.56.4
Percentage of ContractWithCustomerLiabilityRevenueRecognized100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxesAndTaxCredits

us-gaap:DeferredIncomeTaxesAndTaxCredits


Deferred
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
Value34129569.05192104-37.378172622.71417-172.7169124150541329221419898151066970761119276100421021087367214786571105-8.32.25.1
Percentage of DeferredIncomeTaxesAndTaxCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value6.55.75.65.65.85.41.92.02.00.7-0.2-0.3-0.2-0.3-0.8-0.7-0.1-1.5-2.1-2.2
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-28.2-27.4-26.8-26.1-25.5-24.2-20.7-18.9-18.7-19.0-23.4-23.6-23.9-23.1-21.6-21.5-21.1-21.9-21.8-20.4
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses-433.8-480.7-478.6-466.1-439.7-448.1-1089.5-945.0-935.0-2714.311700.07866.711950.07700.02700.03071.421100.01460.01038.1927.3

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-3900000.0-4000000.0-3700000.0-3800000.0-3800000.0-3700000.0-3800000.0-3900000.0-3800000.0-3900000.0-3900000.0-3800000.0-3900000.0-3800000.0-3900000.0-2800000.0-2800000.0-2800000.0-2400000.0-2300000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value400000.0400000.0400000.0400000.0400000.0400000.0600000.0500000.0500000.0600000.0700000.0700000.0600000.0700000.0700000.0700000.0800000.0700000.0800000.0900000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit-10.3-10.0-10.8-10.5-10.5-10.8-15.8-12.8-13.2-15.4-17.9-18.4-15.4-18.4-17.9-25.0-28.6-25.0-33.3-39.1

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1616151515151313131314141414141313131313
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value5050474747474848484848494849484848494849
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets301.8308.5313.2316.0315.9317.2351.1352.6354.4355.5328.2330.2329.7332.9334.2358.8356.6362.0373.3371.2

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.63.64.64.74.64.76.46.56.36.57.57.57.47.57.68.48.48.59.39.2
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2121252526262930303028282828303030313133
Percentage of DefinedBenefitPlanInterestCost602.8608.3543.5544.7567.4555.3457.8466.2479.4470.8384.0380.0387.8377.3396.1360.7359.5367.1337.6360.9

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-19.8-18.3-16.0-15.9-16.6-15.4-9.0-9.0-9.3-7.4-5.1-5.0-5.5-4.7-3.9-1.3-2.3-0.22.42.4
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1513202226161620141315151614151719151917
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-79.3-71.6-125.6-140.9-156.6-105.2-185.6-231.1-150.5-183.8-300.0-318.0-300.0-317.0-405.1-1361.5-839.1-7950.0804.2712.5

us-gaap:DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1 us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1900000.0-100000.0-2400000.0-5200000.0-10000000.0-300000.0-1900000.0-7800000.0-1000000.0-800000.0100000.0-400000.0-300000.0-400000.0-800000.0-2900000.0-5300000.00-1700000.0-700000.0
Percentage of DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.64.23.83.83.54.14.04.13.84.46.05.95.66.26.26.05.66.36.56.5
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1313121211131211111111111112111110111210
Percentage of DefinedBenefitPlanServiceCost377.8331.0336.8328.9334.3319.5307.5282.9310.5256.8190.0201.7210.7193.5183.9185.0185.7185.7192.3167.7

us-gaap:DerivativeGainLossOnDerivativeNet

us-gaap:DerivativeGainLossOnDerivativeNet


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value15-5.40.8-10.9-16.6-23.3-6.9-5.6-0.11.8338.01.9-1.0-2.21.63.12.2-1.83.3-19.4-31.6-24.6-11.0-5.0-5.1-1.01.25.5141.54.26.7-5.50.7-2.3-11.8
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentRisk

wec:CommodityContractFinancialTransmissionRights


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value102.10.99999999999999961.10.61.43.47.63.02.31.27.13.93.74.64.22.23.01.67.11.63.00.73.10.82.1
Percentage of DerivativeGainLossOnDerivativeNet68.0-38.9125.0-10.1-3.6-6.0-49.3-135.7-3000.0127.83.688.8205.3-370.0-209.1262.571.0136.4-88.9215.2-8.2-9.5-2.8-28.2-16.0-41.2

wec:CommodityContractNaturalGas


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value4.8-7.5-0.2-12.0-17.2-24.7-10.3-13.2-3.1-0.5310.4-2.3-5.2-6.9-2.11.3-0.3-2.7-3.4-20.0-33.5-24.3-13.2-5.9-7.1
Percentage of DerivativeGainLossOnDerivativeNet32.0138.9-25.0110.1103.6106.0149.3235.73100.0-27.895.55.0-121.1520.0313.6-131.241.9-13.6150.0-103.0103.1106.098.8120.0118.0139.2

us-gaap:DerivativeNonmonetaryNotionalAmountEnergyMeasure us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeNonmonetaryNotionalAmountEnergyMeasure

wec:CommodityContractFinancialTransmissionRights


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value7.48.47.18.37.27.27.37.88.08.17.67.96.88.28.29.49.49.28.89.97.47.66.68.65.96.2
Percentage of DerivativeNonmonetaryNotionalAmountEnergyMeasure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

wec:CommodityContractNaturalGas


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value47594936445846374356483639483824253437303250382410.013
Percentage of DerivativeNonmonetaryNotionalAmountEnergyMeasure647.3711.9694.4436.1620.8811.1632.9484.6547.5692.6638.2464.6586.8586.6474.4264.9268.1370.7429.5308.1441.9659.2586.4281.4169.5214.5

us-gaap:DividendsCommonStockCash

us-gaap:DividendsCommonStockCash


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-31
Value213213199199199186186186174174174164
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStockCash us-gaap:StatementEquityComponents

us-gaap:Parent


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value213213199199199186186186174174174174164
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0

us-gaap:RetainedEarnings


Dividends
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value213213199199199186186186174174174174164
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0

us-gaap:EarlyRepaymentOfSeniorDebt us-gaap:ConsolidatedEntities, us-gaap:DebtInstrument, us-gaap:SubsequentEventType

us-gaap:EarlyRepaymentOfSeniorDebt

srt:ParentCompany, wec:WECSeniorNotes31DueMarch82022, us-gaap:SubsequentEvent


Early
Period End2020-10-09
Value350
Percentage of EarlyRepaymentOfSeniorDebt100.0

srt:ParentCompany, wec:WECSeniorNotes3375DueJune152021, us-gaap:SubsequentEvent


Early
Period End2020-10-09
Value600
Percentage of EarlyRepaymentOfSeniorDebt171.4

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate


Effective
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312018-01-012017-12-312017-09-302017-06-302017-03-31
Value21.021.0021.00.210.2100.210.210.2100.210.210.210.210000.35
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.00.00.00.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate


Effective
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-2.4-2.5-2.6-0.03-0.0240.033-0.049-0.03-0.0270.017-0.0130.005-0.032
Percentage of EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments

us-gaap:EffectiveIncomeTaxRateReconciliationOtherAdjustments


Effective
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.60.4-0.70.015-0.0020.014-0.028-0.018-0.0090.015-0.05-0.0170.007
Percentage of EffectiveIncomeTaxRateReconciliationOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount


Effective
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
Value-5400000.0-600000.0-1400000.0-4900000.0-300000.0-3900000.0-4400000.0-7200000.0-3000000.0-900000.0-1000000.0-900000.0
Percentage of EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent

us-gaap:EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent


Effective
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-0.2-0.005-0.009-0.016-0.017-0.015-0.004-0.003-0.002
Percentage of EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes

us-gaap:EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes


Effective
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value6.36.36.30.0620.0630.0820.0620.0640.0640.0630.062
Percentage of EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsOther

us-gaap:EffectiveIncomeTaxRateReconciliationTaxCreditsOther


Effective
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
Value4.15.80.23.60.0320.03400.0280.0250.02800.0180.0070.008
Percentage of EffectiveIncomeTaxRateReconciliationTaxCreditsOther100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0

us-gaap:EquityMethodInvestmentDividendsOrDistributions

us-gaap:EquityMethodInvestmentDividendsOrDistributions


Equity
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302017-12-312017-09-302017-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3932403029342750853534101414141313131313121212121212
Percentage of EquityMethodInvestmentDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EquityMethodInvestmentDividendsOrDistributions us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:TransmissionAffiliate


Equity
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value32333439324030302934-0.327508535340.06325311532311010141414
Percentage of EquityMethodInvestmentDividendsOrDistributions0.00.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.0100.00.0100.0100.0

wec:TransmissionAffiliates


Equity
Period End2021-06-302021-03-312020-06-302020-03-31
Value32333240
Percentage of EquityMethodInvestmentDividendsOrDistributions0.00.0100.0100.0

us-gaap:EquitySecuritiesFvNiUnrealizedGain

us-gaap:EquitySecuritiesFvNiUnrealizedGain


Equity
Period End2021-06-302021-03-312020-09-302020-06-302019-09-302019-06-30
Value5.84.05.7110.72.8
Percentage of EquitySecuritiesFvNiUnrealizedGain100.0100.0100.0100.0100.0100.0

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302015-12-312015-09-302015-06-302014-12-312014-09-30
Value6.00.10.10.07.50.00.0120.00.0180.00.0130.00.0150.00.03.90.00.0
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases100.0100.0100.00.0100.00.00.0100.00.00.0100.00.00.0100.00.00.0100.00.00.0100.00.00.0

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements

us-gaap:FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-30
Value1.51.61.70000000000000082.51.92.23.14.25.54.34.15.23.22.92.94.53.73.44.14.22.82.22.52.13.63.73.14.0
Percentage of FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value414242405239153836364133283231394141383830382540141613181717171717161617161515151515141515
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:ScheduleOfEquityMethodInvestmentEquityMethodInvesteeName

wec:ATCHoldcoLLC


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.60.90.40.50.40.2-4.70.4-0.5
Percentage of IncomeLossFromEquityMethodInvestments1.52.10.91.20.80.5-29.61.0-1.4

wec:TransmissionAffiliate


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value4041423952392038373641342933433941413838303825401416131817171717171616171615161515
Percentage of IncomeLossFromEquityMethodInvestments98.597.999.198.899.299.5129.699.0101.4101.1100.7102.7103.8101.8137.3100.0100.0100.0100.0100.0100.0100.0100.0100.0100.7100.0100.8100.0100.0100.0100.6100.0100.699.4100.6100.0100.6100.0103.9100.6100.7

wec:TransmissionAffiliates


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value41425239
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestments us-gaap:StatementBusinessSegments

wec:ElectricTransmissionSegment


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value414242405239153836364133283231394141383830
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions

us-gaap:IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value8.59.28.80.220-0.8-14.98.47.51.9149.42.2-7.1-13.74.07.86.71013-0.723-6.88.63.55.7151615151514151515
Percentage of IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationChangeInEnactedTaxRate

us-gaap:IncomeTaxReconciliationChangeInEnactedTaxRate


Income
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-7900000.0-14600000.0-8300000.0-8900000.0-13000000.032700000.0-12000000.0-7500000.0-13200000.017200000.0-3200000.01500000.0-15500000.0
Percentage of IncomeTaxReconciliationChangeInEnactedTaxRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

us-gaap:IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value69122576562113585152101455259100
Percentage of IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationOtherAdjustments

us-gaap:IncomeTaxReconciliationOtherAdjustments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1.92.3-1.6-1.94.0-1.011-7.1-4.6-4.513-12.6-4.83.6
Percentage of IncomeTaxReconciliationOtherAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationStateAndLocalIncomeTaxes

us-gaap:IncomeTaxReconciliationStateAndLocalIncomeTaxes


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value203618191834132015318.2161729
Percentage of IncomeTaxReconciliationStateAndLocalIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncomeTaxReconciliationTaxCreditsOther

us-gaap:IncomeTaxReconciliationTaxCreditsOther


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value133412119.4187.76.86.2131.74.52.13.8
Percentage of IncomeTaxReconciliationTaxCreditsOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value-220.4150246-46.9-218.93.5262-92.3-392.2124288-76.6-295.660396-63.2-192.3-55.0365-55.1-178.748185
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherCurrentAssets

us-gaap:IncreaseDecreaseInOtherCurrentAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value28-20.223252.9-65.4117-90.4105-125.1122-33.92.5-81.363-42.325-41.2-14.6-21.8-130.463102-58.9
Percentage of IncreaseDecreaseInOtherCurrentAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities

us-gaap:IncreaseDecreaseInOtherCurrentLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value19-2.3-17.943-39.5-27.78053-109.754-110.142-128.51281385.1-72.59072-5.2-144.456-83.899
Percentage of IncreaseDecreaseInOtherCurrentLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities


Increase
Period End2020-12-312020-09-302020-06-302020-03-31
Value21-0.71.932
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities us-gaap:ProductOrService

us-gaap:PublicUtilities


Increase
Period End2020-12-312020-09-30
Value21-0.7
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities us-gaap:ProductOrService, us-gaap:RegulatoryAsset

us-gaap:PublicUtilities, wec:UncollectibleExpense


Increase
Period End2021-06-302021-03-312020-06-302020-03-31
Value-31.1251.932
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities0.00.0100.0100.0

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities us-gaap:ProductOrService, us-gaap:RegulatoryAsset, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:UncollectibleExpense, wec:Illinois


Increase
Period End2021-06-302021-03-312020-06-302020-03-31
Value-18.93.1-3.929
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities0.00.0-205.389.9

us-gaap:PublicUtilities, wec:UncollectibleExpense, wec:Wisconsin


Increase
Period End2021-06-302021-03-312020-06-302020-03-31
Value-12.2225.83.3
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities0.00.0305.310.1

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Increase
Period End2020-12-312020-09-30
Value8.2-3.2
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities38.7457.1

us-gaap:PublicUtilities, wec:Wisconsin


Increase
Period End2020-12-312020-09-30
Value132.5
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities61.3-357.1

us-gaap:IncreaseDecreaseInRegulatoryAssetsAndLiabilities us-gaap:RegulatoryAsset

wec:UncollectibleExpense


Increase
Period End2021-06-302021-03-312020-06-302020-03-31
Value-31.1251.932
Percentage of IncreaseDecreaseInRegulatoryAssetsAndLiabilities0.00.0100.0100.0

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet us-gaap:ConsolidatedEntities, us-gaap:DerivativeInstrumentRisk

us-gaap:InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet

srt:ParentCompany, us-gaap:InterestRateSwap


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-1300000.0-1400000.0-100000.0-1300000.0-600000.0-100000.0100000.0200000.0400000.0400000.0300000.0200000.0500000.0600000.0
Percentage of InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding us-gaap:RelatedPartyTransactionsByRelatedParty

us-gaap:LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding

wec:PowerPurchaseAgreement


Long
Period End2021-06-302021-03-312020-12-31
Value-2.311-2.2
Percentage of LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding100.0100.0100.0

us-gaap:NoncontrollingInterestIncreaseFromBusinessCombination

us-gaap:NoncontrollingInterestIncreaseFromBusinessCombination


Noncontrolling
Period End2021-03-312019-03-312018-09-30
Value6.26937
Percentage of NoncontrollingInterestIncreaseFromBusinessCombination100.0100.0100.0

us-gaap:NoncontrollingInterestIncreaseFromBusinessCombination us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Noncontrolling
Period End2021-03-312019-03-312018-12-312018-09-30
Value6.269-13.237
Percentage of NoncontrollingInterestIncreaseFromBusinessCombination100.0100.00.0100.0

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance


Noncontrolling
Period End2021-06-302021-03-312019-09-302019-06-302019-03-31
Value0.52.04.35.54.8
Percentage of NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance100.0100.0100.0100.0100.0

us-gaap:NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance us-gaap:StatementEquityComponents

us-gaap:NoncontrollingInterest


Noncontrolling
Period End2021-06-302021-03-312019-09-302019-06-302019-03-31
Value0.52.04.35.54.8
Percentage of NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax

us-gaap:OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value100000.0100000.00200000.0300000.000100000.00-1700000.01900000.0-100000.0300000.0100000.0100000.0400000.0-400000.0400000.00000
Percentage of OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax100.0100.00.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-06-30
Value1.01.00.9-0.4-3.3-0.5-2.6-1.5-0.1-0.4-0.2-0.3-0.4-0.4-0.3-0.3-0.3-0.3-0.4110.00.0
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-30
Value-1000000.0-1000000.0-900000.0-400000.0-100000.0200000.0300000.0300000.0400000.0400000.0200000.0300000.0400000.0300000.0300000.0400000.0300000.0300000.0300000.0300000.0400000.0100000.00000
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value0-800000.0-3400000.0-300000.0-2300000.0-1200000.0300000.0000
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax0.0100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-3200000.00300000.01300000.0200000.0-200000.0-900000.0400000.0-900000.0100000.00
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherCostAndExpenseOperating


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-09-30
Value463479604498473455601529503550667553537511602471479501600517522531557535337280249
Percentage of OtherCostAndExpenseOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherCostAndExpenseOperating us-gaap:ConsolidationItems

us-gaap:IntersegmentElimination


Other
Period End2021-06-302021-03-312020-06-302020-03-31
Value-3.9-1.6-1.0-4.5
Percentage of OtherCostAndExpenseOperating-0.8-0.3-0.2-1.0

us-gaap:OtherCostAndExpenseOperating us-gaap:ProductOrService

us-gaap:PublicUtilities


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value458474586493463456584524494548758652631607708581
Percentage of OtherCostAndExpenseOperating98.898.996.998.997.9100.297.199.098.299.6113.5118.0117.4118.6117.6123.2

us-gaap:OtherCostAndExpenseOperating us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:PublicUtilities, wec:Illinois


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value901091281099310412410110712815110410411214399
Percentage of OtherCostAndExpenseOperating19.622.821.321.919.722.820.619.221.223.322.718.919.421.923.821.0

us-gaap:PublicUtilities, wec:OtherStates


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value21232420202125222327262324262821
Percentage of OtherCostAndExpenseOperating4.64.84.14.14.34.84.24.24.65.04.04.24.65.24.74.6

us-gaap:PublicUtilities, wec:Wisconsin


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value346341432363349330434400363392580525502468537460
Percentage of OtherCostAndExpenseOperating74.671.271.672.973.972.672.275.672.371.386.994.993.491.589.197.6

us-gaap:OtherCostAndExpenseOperating us-gaap:StatementBusinessSegments

us-gaap:CorporateAndOther


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-30
Value-2.8-1.8141.03.5-1.6111.31.8-1.04.3-4.42.2-0.31.7-1.52.8-1.6-3.4-3.2-6.3-3.512
Percentage of OtherCostAndExpenseOperating-0.6-0.42.40.20.7-0.42.00.20.4-0.20.6-0.80.4-0.10.3-0.30.6-0.3-0.6-0.6-1.2-0.72.4

us-gaap:IntersegmentElimination


Other
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-