ALK


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

Table of contents



us-gaap:CommonStockValue

us-gaap:CommonStockParOrStatedValuePerShare

us-gaap:PreferredStockParOrStatedValuePerShare

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesAuthorized

us-gaap:CommonStockSharesOutstanding
us-gaap:StatementEquityComponents

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:CostsAndExpenses
us-gaap:StatementBusinessSegments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxExpenseBenefit

us-gaap:InterestExpense
us-gaap:StatementBusinessSegments

us-gaap:InterestPaidNet

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:NonoperatingIncomeExpense
us-gaap:StatementBusinessSegments

us-gaap:OperatingExpenses
us-gaap:StatementBusinessSegments

us-gaap:OperatingIncomeLoss

us-gaap:OtherComprehensiveIncomeLossNetOfTax
us-gaap:StatementEquityComponents

us-gaap:OtherNonoperatingIncomeExpense
us-gaap:ContractWithCustomerSalesChannel
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:ProductOrService, us-gaap:ContractWithCustomerSalesChannel
us-gaap:ProductOrService
us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax
us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments

us-gaap:Revenues
us-gaap:StatementBusinessSegments

us-gaap:Assets
us-gaap:StatementBusinessSegments

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:MarketableSecuritiesCurrent

us-gaap:ReceivablesNetCurrent
us-gaap:ContractWithCustomerSalesChannel

us-gaap:InventoryNet

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:OperatingLeaseRightOfUseAsset
us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssets

us-gaap:AccountsPayableCurrent

us-gaap:AccruedLiabilitiesCurrent

us-gaap:ContractWithCustomerLiabilityCurrent
us-gaap:ProductOrService

us-gaap:DebtCurrent

us-gaap:LiabilitiesCurrent

us-gaap:LongTermDebtCurrent

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LongTermDebt
us-gaap:DebtInstrument
us-gaap:LongtermDebtType

us-gaap:LongTermDebtNoncurrent

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent
us-gaap:RetirementPlanType

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:OperatingLeaseLiability
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:TreasuryStockValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:DepreciationDepletionAndAmortization

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensation

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities
us-gaap:DebtInstrument
us-gaap:ProceedsFromIssuanceOfLongTermDebt

us-gaap:RepaymentsOfLongTermDebt

us-gaap:PaymentsOfDividends

us-gaap:PaymentsForRepurchaseOfCommonStock
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

us-gaap:DeferredTaxLiabilities

us-gaap:UnrecognizedTaxBenefits
us-gaap:AircraftType
alk:AircraftPermanentlyParked

alk:CARESActPSPWarrantsIssuedValue
alk:CARESActPSPProgram

alk:CARESActPayrollTaxRelief

alk:COVID19RelatedCreditsIssued
us-gaap:ContractWithCustomerSalesChannel
alk:ContractwithCustomerLiabilityIncreaseFromIssuanceofCredits

alk:OperatingExpensesExcludingFuel
us-gaap:StatementBusinessSegments

alk:OtherNonoperatingIncomeExpenseOther
us-gaap:StatementBusinessSegments

alk:PSPGrantRecognized
us-gaap:SubsequentEventType

alk:ProceedsFromPayrollSupportProgramGrant
alk:CARESActPSPProgram

alk:RegionalCarrierExpense

alk:SpecialItemsImpairmentChargesAndOther

alk:TotalUnsecuredTermLoanThroughPSPOfCARESAct
alk:CARESActPSPProgram

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued
us-gaap:DebtInstrument
us-gaap:StatementEquityComponents

us-gaap:AircraftMaintenanceMaterialsAndRepairs

us-gaap:AircraftRental

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AssetImpairmentCharges
us-gaap:AircraftType
us-gaap:AircraftType, us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType
us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType

us-gaap:BusinessCombinationAcquisitionRelatedCosts
us-gaap:ContractWithCustomerSalesChannel
us-gaap:ContractWithCustomerLiabilityRevenueRecognized
us-gaap:ProductOrService, us-gaap:ContractWithCustomerSalesChannel

us-gaap:CostOfServicesCatering

us-gaap:DeferredRevenueRefundPayments1
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:IncomeStatementLocation, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanServiceCost

us-gaap:FuelCosts
us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInContractWithCustomerLiability

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes

us-gaap:IncreaseDecreaseInDeferredRevenue

us-gaap:InterestCostsCapitalizedAdjustment

us-gaap:InterestCostsIncurred
us-gaap:StatementBusinessSegments

us-gaap:InterestPaidCapitalized
us-gaap:StatementBusinessSegments

us-gaap:InvestmentIncomeInterest
us-gaap:StatementBusinessSegments

us-gaap:LaborAndRelatedExpense

us-gaap:LandingFeesAndOtherRentals
us-gaap:DebtInstrument
us-gaap:LineOfCreditFacilityMaximumMonthendOutstandingAmount
us-gaap:LitigationCase
us-gaap:LossContingencyDamagesSoughtValue

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax

us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherLaborRelatedExpenses

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsForFlightEquipment

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForRestructuring

us-gaap:PaymentsToAcquireMarketableSecurities

us-gaap:PaymentsToAcquireOtherProductiveAssets

us-gaap:PaymentsToAcquireOtherPropertyPlantAndEquipment
us-gaap:SubsequentEventType
us-gaap:ProceedsFromIssuanceOfDebt

us-gaap:ProceedsFromIssuanceOfSecuredDebt
us-gaap:DebtInstrument
us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities

us-gaap:ProfessionalAndContractServicesExpense

us-gaap:RestructuringCharges

us-gaap:SellingExpense
us-gaap:StatementEquityComponents
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensation

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation
us-gaap:StatementEquityComponents
us-gaap:ShareRepurchaseProgram
us-gaap:StockRepurchasedDuringPeriodValue
alk:CARESActPSPProgram
alk:AdditionalReliefFromPSPOfCARESAct
alk:CARESActPSPProgram, us-gaap:SubsequentEventType
us-gaap:ReportingUnit

alk:AircraftMaintenanceDeposits

alk:COVID19CreditsIssuedBalance

alk:DeferredTaxAssetsLeaseholdMaintenance

alk:DeferredTaxAssetsLeasingArrangement

alk:DeferredTaxAssetsMileagePlan

alk:LAXRedevelopmentProjectTotalExpectedOutlay

alk:LeaseReturnProvisionCurrent

alk:LeaseReturnProvisionNonCurrent

alk:LeasedAircraftReturnCosts
us-gaap:FairValueByMeasurementBasis
alk:NotesPayableFairValueDisclosureBeforePurchasePriceAccountingFairValueAdjustment

alk:NumberOfMainlineAircraftParked
us-gaap:IncomeTaxAuthority
alk:OperatingLossAvailableToOffsetPriorYearIncome
alk:CARESActPSPProgram
alk:PSPInstallmentsReceived
us-gaap:ReportingUnit, us-gaap:SubsequentEventType
us-gaap:RetirementPlanType
alk:PrefundedTrustAccount
us-gaap:AwardType
alk:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedTotalIntrinsicValue
alk:CARESActPSPProgram
alk:TotalExpectedReliefFromPSPOfCARESAct
us-gaap:SubsequentEventType
alk:TotalReliefFromExtensionOfPSP
us-gaap:AircraftType
alk:UnrecordedUnconditionalPurchaseObligationOptiontoPurchaseAdditional

alk:UnsecuredTermLoanThroughPSPOfCARESAct
us-gaap:ReportingUnit, us-gaap:SubsequentEventType
us-gaap:SubsequentEventType

dei:EntityCommonStockSharesOutstanding

us-gaap:AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

us-gaap:AssetsHeldForSaleLongLivedFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:AvailableForSaleSecurities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument
us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesAmortizedCost

us-gaap:AvailableForSaleSecuritiesCurrent

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue

us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:BankOverdrafts

us-gaap:BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments
us-gaap:BalanceSheetLocation
us-gaap:CapitalizedContractCostNet

us-gaap:CashCashEquivalentsAndShortTermInvestments
us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType

us-gaap:ClassOfWarrantOrRightOutstanding
us-gaap:ClassOfWarrantOrRight
us-gaap:ContractWithCustomerSalesChannel
us-gaap:ContractWithCustomerLiability

us-gaap:CreditCardReceivables

us-gaap:DebtInstrumentCarryingAmount

us-gaap:DeferredFinanceCostsNet

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredRevenueCurrent

us-gaap:DeferredRevenueNoncurrent

us-gaap:DeferredTaxAndOtherLiabilitiesNoncurrent

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsInventory

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits

us-gaap:DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOtherFiniteLivedAssets

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment
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:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent
us-gaap:Range, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
us-gaap:Range, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease
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:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFairValueOfPlanAssets
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedPercentage
us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets
us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType
us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations
us-gaap:RetirementPlanType

us-gaap:DepositsOnFlightEquipment
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeAssets
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeAssetsCurrent
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeAssetsNoncurrent
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeLiabilities
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeLiabilitiesCurrent
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeLiabilitiesNoncurrent
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeNonmonetaryNotionalAmount
us-gaap:DerivativeInstrumentRisk, us-gaap:LongtermDebtType
us-gaap:DerivativeNotionalAmount

us-gaap:EmployeeRelatedLiabilitiesCurrent

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
us-gaap:AwardType

us-gaap:EnergyRelatedInventory

us-gaap:FlightEquipmentGross

us-gaap:IncomeTaxExaminationPenaltiesAndInterestAccrued
us-gaap:IncomeTaxAuthority
us-gaap:IncomeTaxReceivable

us-gaap:InventoryValuationReserves
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LessorOperatingLeaseLeaseNotYetCommencedAssumptionAndJudgmentValueOfUnderlyingAssetAmount
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:LiabilitiesFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

us-gaap:LiabilitiesOtherThanLongtermDebtNoncurrent

us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:LineOfCreditFacility
us-gaap:DebtInstrument, us-gaap:SubsequentEventType

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:LongTermDebtFairValue

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear

us-gaap:LongTermDebtPercentageBearingFixedInterestRate

us-gaap:LongTermDebtPercentageBearingVariableInterestRate
us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:NotesPayableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:OperatingLeasesFutureMinimumPaymentsNextRollingTwelveMonths
us-gaap:IncomeTaxAuthority
us-gaap:OperatingLossCarryforwards

us-gaap:OperatingLossCarryforwardsValuationAllowance
us-gaap:RetirementPlanType
us-gaap:OtherDeferredCompensationArrangementsLiabilityClassifiedNoncurrent
us-gaap:RetirementPlanType
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent
us-gaap:IncomeStatementLocation
us-gaap:PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months

us-gaap:PropertyPlantAndEquipmentOther
us-gaap:AircraftType, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:PropertyPlantAndEquipmentSalvageValuePercentage
us-gaap:Range, us-gaap:PropertyPlantAndEquipmentByType
us-gaap:AircraftType, us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits

us-gaap:RestrictedCashAndCashEquivalentsAtCarryingValue

us-gaap:RestrictedCashAndInvestmentsCurrent

us-gaap:RestructuringReserve
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumEmployeeSubscriptionRate

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

us-gaap:TreasuryStockShares

us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:OtherCommitments
us-gaap:UnrecordedUnconditionalPurchaseObligationDueInRemainderOfFiscalYear
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased
us-gaap:AircraftType
us-gaap:UnrecordedUnconditionalPurchaseObligationMinimumQuantityRequired

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Other Nonoperating Income Expense
Balance Sheet
Intangible Assets Net Excluding Goodwill
Assets
Inventory Net
Current Assets
Inventory Net
NonCurrent Assets
Intangible Assets Net Excluding Goodwill
PropertyPlantAndEquipmentNet
Accumulated Depreciation Depletion And Amortization Property Plant And Equipment
Liabilities
Liabilities Noncurrent
Current Liabilities
Accounts Payable Current
Noncurrent Liabilities
Other Liabilities Noncurrent
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Share Based Compensation
NetCashProvidedByUsedInInvestingActivities
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInFinancingActivities
Net Cash Provided By Used In Financing Activities
Shares
Treasury Stock Shares
NonoperatingIncomeExpense
Nonoperating Income Expense
AccountsReceivable
Allowance For Doubtful Accounts Receivable Current

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:CommonStockValue ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█████████▅▅▅▅▅1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.069.069.070.070.070.070.070.270.771.237.937.837.737.437.0NANANA
us-gaap:CommonStockParOrStatedValuePerShare ▄▄1e-081e-08NANANA1e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-061e-061e-061e-061e-061e-061e-061e-061e-061e-06NANA1e-061e-06NANANA
us-gaap:PreferredStockParOrStatedValuePerShare ▄▄1e-081e-08NANANA1e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-081e-061e-061e-061e-061e-061e-061e-061e-061e-061e-06NANA1e-061e-06NANANA
us-gaap:CommonStockSharesIssued █▃▁134.579403133.792045133.567534NA132.989258131.934957131.812173131.770976131.365855131.338245130.813476130.786648130.436306130.378645129.903498129.860836129.63878129.590771129.189634129.127597128.941102128.90141128.442099128.40972128.144917130.551503131.556573133.584527136.84559668.7983368.76669169.99122170.00932770.49283270.37654370.16472670.723971.19557837.866522NANA37.39202737.01014NANANA
us-gaap:CommonStockSharesAuthorized ▄▄400.0400.0NANANA400.0400.0400.0400.0400.0400.0400.0400.0400.0400.0400.0400.0200.0200.0200.0200.0200.0200.0200.0200.0200.0200.0200.0200.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0NANA100.0100.0NANANA
us-gaap:CommonStockSharesOutstanding █▃▁125.229459124.442101124.21759NA123.639314122.585013123.000307123.277911123.338144123.504308123.19443123.360846123.203707123.350124123.060638123.387158123.520517123.729188123.328051123.266014123.079519123.913223125.175325126.701469128.024917130.444006131.481473133.468522136.73803468.78855768.74595369.650542NANA70.376543NA70.771.435.5NANANANANANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁126.825124.299NA123.647123.965124.123NA124.067124.301123.915NA123.864124.036123.63NA124.22124.332124.299NA123.833123.988125.328NA128.205130.255132.23NA136.158064138.71113269.410618NA70.69271.15971.414NA71.88372.272.659NA36.61936.73736.841NA36.8336.69736.393
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic █▁124.977124.299NA123.647123.296122.818NA123.28123.418123.291NA123.224123.268123.155NA123.467123.573123.495NA123.149123.25124.55NA127.308129.236131.12NA134.865408137.27446268.667217NA69.7870.25270.431NA70.96370.99671.192NA35.97735.98335.994NA35.89835.69835.667
us-gaap:EarningsPerShareBasic ▇▃▁▁▃▃▆▇▆▄▄▆▆▄▇▆▆▅▅▆▆▆▆▆▆▅▅▆▅▆▅█▆▅▅▆▅▅▆▆▅▆▆▇▆▄3.18-1.05-3.6000000000000005-3.49-1.74-1.891.48000000000000042.612.120.030.189999999999999951.761.570.033.0400000000000012.152.40.80.92999999999999972.082.111.471.53000000000000022.151.81.131.11999999999999971.471.21.371.13999999999999974.131.490.520.63999999999999972.30.950.571.792.150.82.061.79999999999999983.411.640.15
us-gaap:EarningsPerShareDiluted ▇▃▁▁▃▃▆▇▆▄▄▆▆▄▇▆▆▅▅▆▆▆▆▆▆▅▅▆▅▆▅█▆▅▅▆▅▅▆▆▅▆▆▇▆▄3.13-1.05-3.6000000000000005-3.49-1.73-1.871.45000000000000022.62.110.030.180000000000000161.751.560.033.042.142.380.790.91000000000000012.072.11.461.50999999999999982.141.791.121.10999999999999991.451.191.351.124.081.470.510.63000000000000032.270.930.561.752.120.782.011.753.321.60.15
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 Cost Ratio us-gaap:StatementBusinessSegments alk:AirGroupAdjustedNANANA701.0421.01636.0NA2389.02288.01876.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Cost Ratio us-gaap:StatementBusinessSegments alk:AlaskaMainlineNANANA511.0320.01376.0NA2015.01929.01570.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Cost Ratio us-gaap:StatementBusinessSegments alk:AlaskaRegionalNANANA190.0101.0258.0NA373.0357.0305.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Cost Ratio us-gaap:StatementBusinessSegments alk:HorizonNANANA95.081.0105.0NA112.0112.0117.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 Cost Ratio us-gaap:StatementBusinessSegments us-gaap:IntersegmentEliminationNANANA-95.0-81.0-103.0NA-111.0-110.0-116.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 EBT Margin us-gaap:StatementBusinessSegments alk:AirGroupAdjustedNANA808.0701.0421.01636.02228.02389.02288.01876.02064.02212.02156.01832.0-5952.02110.02102.01749.0-4407.01566.01494.01347.0NANANANANANANANANANANANANANANA1039.3-3273.51198.11110.2965.2NANANANA
 EBT Margin us-gaap:StatementBusinessSegments alk:AlaskaMainlineNANA622.0511.0320.01376.01867.02015.01929.01570.01741.01884.01859.01579.0-5147.01820.01823.01517.0-3661.01293.01246.01122.0NANANANANANANANANANANANANANANA849.7-2679.5981.4912.9785.3NANANANA
 EBT Margin us-gaap:StatementBusinessSegments alk:AlaskaRegionalNANA185.0190.0101.0258.0359.0373.0357.0305.0323.0326.0296.0252.0-802.0289.0278.0230.0-742.0271.0247.0224.0NANANANANANANANANANANANANANANA187.7-587.7214.7195.4177.5NANANANA
 EBT Margin us-gaap:StatementBusinessSegments alk:HorizonNANA105.095.081.0105.0110.0112.0112.0117.0133.0130.0138.0111.0106.0113.0109.098.099.0110.0111.0104.0105.0105.099.099.094.099.087.091.094.088.091.094.097.096.089.088.983.493.295.497.0169.6180.9171.1NA
 EBT Margin us-gaap:StatementBusinessSegments us-gaap:IntersegmentEliminationNANANA-95.0-81.0-103.0-108.0-111.0-110.0-116.0-133.0-128.0-137.0-110.0-109.0-112.0-108.0-97.0-102.0-109.0-110.0-103.0-105.0-105.0-99.0-99.0-94.0-99.0-87.0-91.0-94.0-88.0-91.0-94.0-97.0-96.0-89.0-87.0-89.7-91.2-93.5-94.6NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
 TTM Greenblatt ROC _ _█▄▁▁▃▃▆▇▇▅▅▆▆▅▆▇█▆▆▇▇▆▆▇▇▆▆▇▆▆▅█▆▅▅▆▅▅▅▆▅▅▅549.0-161.0-595.0-571.0-288.0-321.0252.0422.0364.025.046.0297.0271.029.0162.0439.0493.0166.0241.0400.0418.0290.0255.0433.0372.0238.0242.0316.0263.0141.0130.0470.0174.064.074.3269.5115.872.4114.1143.257.8133.8119.3NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:ComprehensiveIncomeNetOfTax █▄▁▂▃▃▆▇▇▅▅▇▆▅▇▇▇▆▆▇▇▆▆▇▇▆▅▆▆▆▇▇▆▅▅▆▅▅▄▅▅▅404.0-131.0-491.0-423.0-190.0-249.0137.0323.0273.019.03.0224.0198.06.0283.0270.0301.0105.093.0259.0267.0193.0191.0275.0235.0154.016.0198.0168.096.0309.0299.0109.044.0-18.1170.669.148.4-69.781.532.577.7NANANANA
us-gaap:CostsAndExpenses ▇▇▃▇▇█▁███▆▆▆978.0958.0-3895.01272.0709.01957.0-5534.01967.01924.01851.051.057.058.0NA55.061.066.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments █▄▁▁▃▃▆▇▇▅▅▇▆▅▆▇█▆▆▇▇▇▆▇▇▆▆▇▆▆▆█▆▅▅▆▅▅▅▆▅▆▅▆▅▅528.0-173.0-643.0-589.0-291.0-317.0243.0416.0351.06.036.0284.0259.06.0149.0427.0479.0152.0231.0402.0420.0292.0259.0437.0376.0240.0242.0316.0265.0152.0125.0463.0169.059.072.7265.6109.166.6100.7125.347.0120.7103.5198.294.010.2
us-gaap:IncomeTaxExpenseBenefit ▇▄▁▂▄▃▆▆▆▅▅▆▆▅▁██▆▇▇█▇▆█▇▆▆▇▇▆▆█▆▅▅▇▆▅▅▆▅▆▆▆▅▅131.0-42.0-196.0-158.0-77.0-85.062.094.089.02.013.067.066.02.0-224.0161.0183.053.0117.0146.0160.0108.068.0163.0142.091.094.0118.0100.058.047.0174.065.022.028.4102.241.625.836.747.818.246.538.775.835.44.9
us-gaap:InterestExpense █▁39.032.0NANA17.013.018.018.020.022.020.022.025.024.026.026.026.025.022.011.09.013.010.010.011.011.012.012.012.012.014.013.014.016.015.115.117.216.618.225.720.023.426.929.526.325.6
us-gaap:InterestPaidNet ▃█▃▃▃▂▃▃▃▄▃▄▃▄▃▅▃▅▃▂▁▂▁▁▁▂▁▃▂▃▂▃▂▃▂▃▂▃▂▅▃▅▅▆▄▅11.050.012.013.016.09.012.014.016.018.012.021.015.024.016.026.016.026.012.04.00.08.0-1.01.01.07.02.010.05.011.04.010.06.015.05.815.69.015.67.626.314.625.126.731.818.928.6
us-gaap:NetIncomeLoss █▄▁▁▃▃▆▇▇▅▅▇▆▅█▇▇▆▆▇▇▆▆▇▇▆▆▆▆▅▅▇▆▅▅▆▅▅▅▅▅▅▅▆▅▅397.0-131.0-447.0-431.0-214.0-232.0181.0322.0262.04.023.0217.0193.04.0373.0266.0296.099.0114.0256.0260.0184.0191.0274.0234.0149.0148.0198.0165.094.078.0289.0104.037.044.3163.467.540.864.077.528.874.264.8122.458.65.3
us-gaap:NonoperatingIncomeExpense ▄▅▁▅▆▇▆▆▅▄▆▅▅▄▅▅▅▅▆▇▇▇▇▇▇▇▇▇▇█▆▆▆▆▇▆▆▆▅▅▅▅▅▄▅▅-21.0-12.0-48.0-18.0-3.04.0-9.0-6.0-13.0-19.0-10.0-13.0-12.0-23.0-13.0-12.0-14.0-14.0-10.02.02.02.04.04.04.02.00.00.02.011.0-5.0-7.0-5.0-5.0-1.6-3.9-6.7-5.8-13.4-17.9-10.8-13.1-15.8-18.7-15.7-15.5
 us-gaap:NonoperatingIncomeExpense us-gaap:StatementBusinessSegments alk:AirGroupAdjusted▁▃▁▂▅▇▄▄▃▂▄▃▃▁▃▃▃▃▄▆▆▆▇▇▇▆▆▆▆█▅▄▅▅▅▅▄▅▃▂▄▃-21.0-12.0-22.0-18.0-3.04.0-9.0-6.0-13.0-19.0-10.0-13.0-12.0-23.0-13.0-12.0-14.0-14.0-10.02.02.02.04.04.04.02.00.00.02.011.0-5.0-7.0-5.0-5.0-1.6-3.9-6.7-5.8-13.4-17.9-10.8-13.1NANANANA
 us-gaap:NonoperatingIncomeExpense us-gaap:StatementBusinessSegments alk:AlaskaMainline▁▃▁▂▅▇▄▅▄▂▄▄▄▂▃▃▂▂▃▆▆▅▆▆▆▆▅▆▆█▅▆▅▅▅▅▄▄▃▂▃▃-16.0-7.0-18.0-12.00.011.0-4.00.0-6.0-11.0-3.0-6.0-4.0-12.0-9.0-7.0-11.0-12.0-8.05.05.01.04.05.05.05.03.04.05.015.02.04.01.0-1.01.7-0.1-3.2-2.4-10.0-13.8-6.9-8.9NANANANA
 us-gaap:NonoperatingIncomeExpense us-gaap:StatementBusinessSegments alk:Horizon▄▄▃▃▄▄▃▂▂▁▃▄▄▄▅▄▆▆▇▆▅▇▇▅▆▅█▄▅▅▅▅▅▅▅▅▅▅▅▅▄▅▅▄▄-5.0-5.0-6.0-6.0-5.0-5.0-6.0-7.0-7.0-8.0-6.0-5.0-5.0-4.0-3.0-4.0-2.0-2.0-1.0-2.0-3.0-1.0-1.0-3.0-2.0-3.00.0-4.0-3.0-3.0-3.0-3.0-3.0-3.0-3.0-3.7-3.7-3.6-3.5-3.9-4.2-3.9-3.3-4.1-4.8NA
us-gaap:OperatingExpenses █▁978.0958.0NANA709.01957.01976.01967.01924.01851.02018.01915.01885.01803.01800.01681.01609.01583.01283.01166.01076.01057.01122.01082.01065.01031.01064.01149.01112.01081.01080.01087.01082.01069.01058.01002.71097.4966.9930.21054.91052.4831.4839.2851.1866.5803.9
us-gaap:OperatingIncomeLoss █▄▁▁▃▃▆▇▇▅▅▆▆▅▆▇█▆▆▇▇▆▆▇▇▆▆▇▆▆▅█▆▅▅▆▅▅▅▆▅▅▅▆▅▅549.0-161.0-595.0-571.0-288.0-321.0252.0422.0364.025.046.0297.0271.029.0162.0439.0493.0166.0241.0400.0418.0290.0255.0433.0372.0238.0242.0316.0263.0141.0130.0470.0174.064.074.3269.5115.872.4114.1143.257.8133.8119.3216.9109.725.7
us-gaap:OtherComprehensiveIncomeLossNetOfTax 7.0NA-44.08.024.0-17.0-44.01.011.015.0-20.07.05.02.0-90.04.05.06.0-21.03.07.09.00.01.01.05.0-132.00.03.02.0231.010.05.07.0-62.47.21.67.0-134.24.03.7NANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▇▇▅▆▆▆▃▄▂▂▄▂▄▁▄▄▄▄▅▄▄▅▄▄▅▄▄▅▆█▄▃▄▅▅▅▅▅▃▅▅▅▅▅▅▅9.010.01.05.06.05.0-6.0-3.0-7.0-10.0-3.0-7.0-1.0-12.00.00.0-1.00.01.00.0-3.01.00.00.01.00.00.02.05.013.0-1.0-5.00.02.03.42.31.91.4-5.71.21.30.92.91.81.30.9
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ContractWithCustomerSalesChannel alk:CargoandOtherRevenue▇▃▂▃▁▃▅██▅▅▆▅▂▂▄▄57.044.043.045.039.046.052.060.059.050.052.055.051.041.042.047.048.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ContractWithCustomerSalesChannel alk:MileagePlanRevenue▆▃▃▂▁▆██▇▆▆▆▇▅▅▅▆272.0178.0182.0148.0129.0261.0312.0304.0290.0263.0265.0267.0275.0246.0240.0239.0252.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ContractWithCustomerSalesChannel alk:PassengerRevenue▅▂▂▂▁▅▇██▆▇▇▇▆▆▇▇1352.0659.0657.0572.0309.01481.02057.02211.02111.01716.01907.02043.01997.01684.01796.01958.01945.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:CargoServices,alk:CargoandOtherRevenue▆▂▄▄▃▁▄▇█▄▅▇▆▂▂▅▅34.027.029.031.028.024.029.036.038.030.032.036.034.026.027.032.032.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:MileagePlanServices,alk:PassengerRevenue▆▂▂▁▁▆██▇▆▆▆▇▅▅▅▅154.084.074.064.056.0152.0193.0186.0172.0153.0160.0153.0167.0139.0136.0134.0143.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:MileagePlanServicesOther,alk:MileagePlanRevenue█▄▆▃▁▆███▇▆▇▆▆▆▆▆118.094.0108.084.073.0109.0119.0118.0118.0110.0105.0114.0108.0107.0104.0105.0109.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:OtherServices,alk:CargoandOtherRevenue▇▄▃▃▁▇▇█▆▆▆▅▄▃▃▃▄23.017.014.014.011.022.023.024.021.020.020.019.017.015.015.015.016.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:PassengerAncillaryServices,alk:PassengerRevenue▄▂▂▂▁▆▇█▇▆▆▇▇▆▆▇▇84.050.049.049.031.0116.0139.0157.0147.0124.0129.0146.0137.0117.0123.0141.0134.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:PassengerTickets,alk:MileagePlanRevenue█▁154.084.0NANA56.0152.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel alk:PassengerTickets,alk:PassengerRevenue▅▂▂▂▁▅▇██▆▇▇▇▆▇▇▇1114.0525.0534.0459.0222.01213.01725.01868.01792.01439.01618.01744.01693.01428.01537.01683.01668.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel us-gaap:CargoAndFreight,alk:CargoandOtherRevenue▇▃▂▃▁▃▅██▅▅▆▅▂▂▄▄57.044.043.045.039.046.052.060.059.050.052.055.051.041.042.047.048.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel us-gaap:Passenger,alk:MileagePlanRevenueNANA74.064.056.0152.0193.0186.0172.0153.0160.0153.0167.0139.0136.0134.0143.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService,us-gaap:ContractWithCustomerSalesChannel us-gaap:Passenger,alk:PassengerRevenue▅▂▂▂▁▅▇██▆▇▇▇▆▆▇▇1352.0659.0657.0572.0309.01481.02057.02211.02111.01716.01907.02043.01997.01684.01796.01958.01945.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService alk:MileagePlanServicesOther█▁118.094.0NA84.073.0109.0NA118.0118.0110.0NA114.0108.0107.0NA105.0109.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService us-gaap:CargoAndFreight█▁57.044.0NA45.039.046.0NA60.059.050.0NA55.051.041.0NA47.048.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService us-gaap:Passenger█▁1352.0659.0NA572.0309.01481.0NA2211.02111.01716.0NA2043.01997.01684.0NA1958.01945.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments alk:CapacityPurchaseAgreements,alk:Horizon█▁111.0104.0NA95.081.0105.0NA112.0112.0116.0NA128.0137.0110.0NA112.0108.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments alk:CapacityPurchaseAgreements,us-gaap:IntersegmentEliminationNANANA-95.0-81.0-105.0NA-112.0-112.0-116.0NA-128.0-137.0-110.0NA-112.0-108.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments alk:MileagePlanServicesOther,alk:AirGroupAdjusted█▁118.094.0NA84.073.0109.0NA118.0118.0110.0NA114.0108.0107.0NA105.0109.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments alk:MileagePlanServicesOther,alk:AlaskaMainline█▁102.080.0NA65.056.098.0NA107.0105.0100.0NA104.099.098.0NA97.0101.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments alk:MileagePlanServicesOther,alk:AlaskaRegional█▁16.014.0NA19.017.011.0NA11.013.010.0NA10.09.09.0NA8.08.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:CargoAndFreight,alk:AirGroupAdjusted█▁57.044.0NA45.039.046.0NA60.059.050.0NA55.051.041.0NA47.048.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:CargoAndFreight,alk:AlaskaMainline█▁55.044.0NA45.039.044.0NA58.057.048.0NA53.049.040.0NA46.045.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:CargoAndFreight,alk:ConsolidatingAndOther2.0NANANA0.02.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:CargoAndFreight,us-gaap:IntersegmentEliminationNANANA0.00.02.0NA1.02.00.0NA0.00.00.0NA0.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Passenger,alk:AirGroupAdjusted█▁1352.0659.0NA572.0309.01481.0NA2211.02111.01716.0NA2043.01997.01684.0NA1958.01945.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Passenger,alk:AlaskaMainline█▁1072.0506.0NA401.0225.01234.0NA1850.01767.01422.0NA1727.01711.01441.0NA1677.01677.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService,us-gaap:StatementBusinessSegments us-gaap:Passenger,alk:AlaskaRegional█▁280.0153.0NA171.084.0247.0NA361.0344.0294.0NA316.0286.0243.0NA281.0268.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:StatementBusinessSegments alk:AirGroupAdjusted▇▇▇▇▆▇████████▁██▇▂▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▇▃▇▇▇1527.0797.0808.0701.0421.01636.02228.02389.02288.01876.02064.02212.02156.01832.0-5952.02110.02102.01749.0-4407.01566.01494.01347.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01039.3-3273.51198.11110.2965.2NANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:StatementBusinessSegments alk:AlaskaMainline▇▇▇▇▆▇████████▁███▂▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▇▃▇▇▇1229.0630.0622.0511.0320.01376.01867.02015.01929.01570.01741.01884.01859.01579.0-5147.01820.01823.01517.0-3661.01293.01246.01122.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0849.7-2679.5981.4912.9785.3NANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:StatementBusinessSegments alk:AlaskaRegional█▇▇▇▆▇███████▇▁▇▇▇▁▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▇▂▇▇▇296.0167.0185.0190.0101.0258.0359.0373.0357.0305.0323.0326.0296.0252.0-802.0289.0278.0230.0-742.0271.0247.0224.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0187.7-587.7214.7195.4177.5NANANANA
 us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:StatementBusinessSegments alk:Horizon▃▃▃▂▁▃▃▃▃▄▅▄▅▃▃▃▃▂▂▃▃▃▃▃▂▂▂▂▁▂▂▁▂▂▂▂▂▂▁▂▂▂▇█▇111.0104.0105.095.081.0105.0110.0112.0112.0117.0133.0130.0138.0111.0106.0113.0109.098.099.0110.0111.0104.0105.0105.099.099.094.099.087.091.094.088.091.094.097.096.089.088.983.493.295.497.0169.6180.9171.1NA
us-gaap:Revenues ▇▇▇▇▆▇████████▁██▇▂▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▆▆▇▃▇▇▇▇▇▇▇1527.0797.0808.0701.0421.01636.02228.02389.02288.01876.02064.02212.02156.01832.0-5952.02110.02102.01749.0-4407.01566.01494.01347.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01039.3-3273.51198.11110.2965.2958.51068.0976.2829.6
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:Assets ██▇█▇▇▇▇▇▆▅▅▅▅▅▅▅▅▅▄▂▂▂▂▂▂▂▂▂▂▂▂▂▁▁▁▁▁▁▁▁▁▁14656.014262.014046.014749.013998.013363.012993.012983.012951.012640.010912.010893.011055.010848.010740.010739.010720.010302.09962.08699.07035.06829.06533.06564.06480.06410.06181.06236.06314.06061.05838.05862.05852.05644.05505.05436.15423.65382.05195.05260.25233.85111.45016.6NANANA
us-gaap:LiabilitiesAndStockholdersEquity ██▇█▇▇▇▇▇▆▅▅▅▅▅▅▅▅▄▃▂▂▂▂▂▂▂▂▂▁▁▁▁▁▁14656.014262.014046.014749.013998.013363.012993.012983.012951.012640.010912.010893.011055.010848.010740.010739.010720.010302.09962.08699.07035.06829.06533.06564.06480.06410.06181.06236.06314.06061.05838.05862.05852.05644.05505.0NA5423.65382.05195.05260.25233.85111.45016.6NANANA
us-gaap:StockholdersEquity ▆▄▅▆▇▇██▇▇▇▇▆▆▇▆▅▅▅▄▄▃▃▃▃▃▃▃▃▃▂▂▁▁▁3324.02875.02988.03454.03861.04015.04331.04252.03973.03746.03751.03791.03593.03439.03721.03491.03264.03014.02931.02864.02627.02455.02411.02365.02219.02166.02127.02229.02200.02095.02029.01802.01543.01462.01421.0NA1283.01218.01173.21264.31206.51170.11105.4NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:AssetsCurrent █▇▆▇▅▃▂▂▂▂▁▂▂▂▂▂▃▂▂▅▂▂▁▁▁▁▁▁▂▂▁▂▂▁▁4771.04284.04006.04465.03244.02572.02037.02202.02218.02001.01787.02056.02216.02114.02146.02214.02425.02213.02050.03600.02003.01923.01663.01715.01654.01776.01756.01799.02020.01934.01762.01935.01986.01839.01737.0NA1698.41656.91595.51726.31675.71596.01662.0NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▅▅▆█▇▄▂▂▂▂▁▂▁▂▂▁▂▂▂█▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁1025.01076.01370.01855.01509.0811.0221.0237.0244.0215.0105.0174.0102.0177.0194.0144.0198.0183.0328.01818.081.078.073.088.045.051.0107.034.022.090.080.041.057.095.0122.027.535.448.2102.267.567.060.289.5129.2108.1117.7
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents ▅▅▆█▇▄▁▂▂▁▁▁▁▁▁▁▁1042.01092.01386.01867.01520.0822.0232.0249.0254.0225.0114.0184.0108.0183.0197.0144.0198.0NA328.0NANANA73.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:MarketableSecuritiesCurrent █▆▅▄▂▂▂▂▂▂▂▂▃▂▃▃▄▃▂▃▃▃▂▂▂▂▁▂▃▂▂▃▂▂▂▂▂▁▁▂▁▁▁2926.02473.01976.01904.01294.01314.01300.01382.01383.01221.01131.01223.01466.01351.01427.01596.01724.01527.01252.01408.01526.01486.01255.01170.01147.01261.01110.01309.01488.01330.01250.01404.01372.01170.01130.01158.11150.01093.01038.71198.31086.5982.31118.7NANANA
us-gaap:ReceivablesNetCurrent █▇▇▄▄▃▄▅▅▅▅▆▆▅▄▄▄▄▄▃▃▃▂▂▂▂▃▂▂▂▁▂▂▂▁▂▂▂▁▁▂▂▁567.0517.0480.0321.0280.0279.0323.0377.0389.0358.0366.0422.0411.0350.0341.0301.0326.0321.0302.0232.0254.0235.0212.0205.0194.0187.0259.0178.0203.0212.0152.0182.0195.0188.0130.0185.4169.4168.3136.4148.3167.8161.2120.1NANANA
us-gaap:InventoryNet ▃▄▄▄▄▇█▆▄▄▅▄▄▆▄▄▃▂▂▁▁▁▃▃▄▃▄▆▅▄▅▅▅▅▄▃▂▁▁▁▃▁▁52.057.057.057.056.068.072.063.055.058.060.057.057.062.057.057.052.050.047.044.045.045.051.052.058.052.058.064.061.058.060.060.059.061.058.052.547.845.344.344.352.645.745.1NANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent ▅▃▂█▂▂▂▃▃▃▂▄▄▄▃▂▂▃▂▂▂▁▁▁▁▂▂▂▃▂▂▂▂▃▂▂▂▂▂201.0161.0123.0328.0105.0100.0121.0143.0147.0149.0125.0180.0180.0174.0127.0116.0125.0132.0121.098.097.079.072.074.087.0102.0105.0100.0134.0124.095.0105.0114.0132.0123.0116.1121.7100.993.0NANANA106.7NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:PropertyPlantAndEquipmentGross ▇▇▇▇█████▇▇▇▇▇▆▆▆▆▅▄▄▄▄▄▃▃▃▂▂▂▂▂▁▁▁9831.09760.09742.09841.010229.010161.010388.010227.010051.09862.010023.09662.09584.09414.09275.09308.09061.08817.08595.07908.07743.07529.07416.07268.07165.06881.06616.06494.06291.06068.05961.05826.05715.05564.05472.0NA5288.05230.95066.64996.24853.04763.84626.6NANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ██▇▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▃▃▂▂▂▂▂▁▁▁▁▁3703.03616.03531.03460.03434.03307.03486.03393.03307.03233.03242.03167.03091.03011.02991.03078.03059.03008.02929.02877.02784.02699.02614.02534.02460.02384.02317.02250.02189.02138.02068.02034.01990.01925.01863.01805.31740.61727.21665.11646.11603.11561.61509.5NANANA
us-gaap:PropertyPlantAndEquipmentNet ▆▆▇▇█████▇█▇▇▇▇▇▆▆▅▄▄▄▄▃▃▃▂▂▂▂▂▁▁▁▁6128.06144.06211.06381.06795.06854.06902.06834.06744.06629.06781.06495.06493.06403.06284.06230.06002.05809.05666.05031.04959.04830.04802.04734.04705.04497.04299.04244.04102.03930.03893.03792.03725.03639.03609.0NA3547.43503.73401.53350.13249.93202.23117.1NANANA
us-gaap:Goodwill ███████████████▁▆▇▁1943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01943.01934.01940.01942.01934.0NANANA0.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill ▁▁▂▂▂▂▄▄▅▅▅▅▆▆▆▇▇▇█103.0105.0107.0107.0109.0110.0122.0123.0125.0127.0127.0128.0130.0132.0133.0135.0137.0139.0143.0NANANA0.0NANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingLeaseRightOfUseAsset ▇▇▇▇▇▇████▁1375.01423.01400.01516.01568.01584.01711.01647.01696.01715.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▇██▇▇▆▆▅▅▅▆▆▆▅▅▅▄▄▃▁▁▁▁▂▂▃▂▄▄▄▃▂▂▃▂▂▃▃▂▃▄▄▃336.0363.0379.0337.0339.0300.0278.0234.0225.0225.0274.0271.0273.0256.0234.0226.0216.0199.0169.068.073.076.068.0115.0121.0137.0126.0193.0192.0197.0179.0126.0128.0143.0120.0129.0138.5148.6127.8136.6223.3211.6167.6NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:AccountsPayableCurrent █▆▅▄▄▅▇▅██▆▅▅▄▅▄▄▄▃▂▂▁▁▁▁▁▁▂▂▂▂▁▂▄▂▂▅▆▄▃▂▁▁159.0133.0108.093.0102.0119.0146.0120.0156.0157.0132.0114.0115.0102.0120.097.095.095.092.071.078.063.063.061.056.057.062.068.071.075.064.060.071.0101.065.070.2110.8129.0103.688.071.359.260.2NANANA
us-gaap:AccruedLiabilitiesCurrent ▅▃▂▂▁▂▂▃▃▃▂▂▃▂▇▇█▇▇▅▆▆▅▅▅▅▄▅▅▅▄▅▅▄▃▃▃▃▃▃▃▃▃661.0541.0424.0406.0327.0382.0431.0476.0505.0480.0416.0452.0483.0433.0918.0886.0979.0909.0878.0735.0757.0809.0661.0698.0736.0731.0629.0680.0706.0672.0612.0676.0711.0568.0539.0537.0558.5551.5513.3491.0544.0533.4501.2NANANA
us-gaap:ContractWithCustomerLiabilityCurrent NANANA1071.01131.01110.0900.0NANANA788.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ContractWithCustomerLiabilityCurrent us-gaap:ProductOrService alk:AirTrafficLiabilityNANA1073.0NANANA900.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ContractWithCustomerLiabilityCurrent us-gaap:ProductOrService alk:MileagePlanRevenue█▄▁922.0818.0733.0NANANA750.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ContractWithCustomerLiabilityCurrent us-gaap:ProductOrService alk:PassengerRevenue█▄▁1533.01297.01073.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DebtCurrent ▁█▆869.01246.01138.0NANANA235.0265.0288.0300.0486.0345.0314.0387.0307.0334.0337.0332.0319.0275.0117.0116.0115.0117.0116.0118.0117.0115.0114.0113.0117.0111.0110.0106.0161.0167.2183.4210.1207.9213.6253.9169.8221.2NANANA
us-gaap:LiabilitiesCurrent ██▇▇▆▆▅▅▅▅▄▄▄▄▄▄▄▄▃▂▂▂▂▂▂▂▁▂▂▂▁▁▂▁▁4846.04762.04293.04207.04120.03730.03201.03346.03534.03386.02942.02888.03036.02992.02700.02765.02974.02835.02535.02123.02061.02069.01806.01854.01927.01880.01671.01767.01864.01755.01580.01650.01756.01598.01501.0NA1664.31673.21509.61518.31628.01484.41424.7NANANA
us-gaap:LongTermDebtCurrent ▁█▆869.01246.01138.0NANANA235.0265.0288.0300.0486.0345.0314.0387.0307.0334.0337.0332.0319.0275.0117.0116.0115.0117.0116.0118.0117.0115.0114.0113.0117.0111.0110.0106.0161.0167.2183.4210.1207.9213.6253.9NA221.2NANANA
us-gaap:OperatingLeaseLiabilityCurrent ▇████▇▇▇██▁263.0271.0290.0283.0273.0266.0269.0268.0273.0275.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:LiabilitiesNoncurrent NANANA4416.04468.04415.04197.03941.03906.03844.02602.02530.02428.02355.02338.02116.02013.01922.01851.01851.01838.01774.01745.01752.01705.01714.01697.01530.01505.01490.01475.01628.01739.01744.01712.0NA1519.21453.91413.21298.81244.41181.71173.5NANANA
us-gaap:LongTermDebt ▇▇▇█▅▅▃▃▄▄▄▄▅▅▅▆▆▆▆▄▁▁▁▁▁▁▁▁▂▁▂▂▂▂▂▂▂▂▂▃▃3188.03571.03495.03822.02636.02262.01499.01709.01826.01964.02103.02029.02312.02449.02569.02701.02806.02863.02964.02136.0626.0647.0686.0710.0745.0768.0803.0825.0859.0834.0871.0893.0924.0946.01032.01066.11140.51247.01306.91392.41408.8NA1534.2NANANA
us-gaap:LongTermDebtNoncurrent ▁▂█2319.02325.02357.0NANANA1264.01444.01538.01664.01617.01684.01998.02062.02262.02367.02469.02531.02645.01861.0509.0531.0571.0593.0629.0650.0686.0710.0745.0721.0754.0782.0814.0840.0871.0898.9957.11036.91099.01178.81154.91275.21313.0NANANA
us-gaap:LongTermDebtAndCapitalLeaseObligations NANANA2672.01549.01203.01264.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DeferredIncomeTaxLiabilitiesNet █▁▅439.0365.0407.0NANANA715.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ███▇▇▇▇▅▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▃▃▃▃▁▁▁▁▅▅▆▆▅▅▅▅▄▄▄▄660.0663.0665.0601.0581.0577.0571.0467.0522.0513.0503.0470.0464.0458.0453.0323.0336.0334.0331.0272.0271.0270.0270.0249.0247.0247.0246.0124.0123.0122.0123.0461.0470.0479.0489.0447.9452.9458.4463.4336.3361.2364.1367.1NANANA
us-gaap:OtherLiabilitiesNoncurrent ▆▇█▇▅▃▃▃▂▃▆▆▆▆▇▆▆▇▆▅▅▅▅▅▅▅▅▄▄▄▄▅▅▅▅▃▃▂▂▂▂▁▁422.0482.0524.0476.0373.0253.0232.0213.0197.0210.0418.0428.0417.0423.0451.0429.0427.0438.0417.0355.0366.0359.0362.0341.0339.0332.0327.0312.0315.0309.0308.0318.0318.0332.0334.0213.0204.8184.1176.7170.3148.6108.6123.0NANANA
us-gaap:OperatingLeaseLiabilityNoncurrent ▇▇▇▇██████▁1222.01283.01268.01320.01376.01375.01439.01376.01424.01443.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AircraftNANA195.0NANANA216.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CPAAircraftNANA84.0NANANA79.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CorporaterealestateNANA7.0NANANA6.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AircraftNANA135.0NANANA190.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CPAAircraftNANA84.0NANANA79.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CorporaterealestateNANA7.0NANANA5.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AircraftNANA83.0NANANA133.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CPAAircraftNANA84.0NANANA79.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CorporaterealestateNANA6.0NANANA5.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AircraftNANA76.0NANANA81.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CPAAircraftNANA84.0NANANA79.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CorporaterealestateNANA4.0NANANA5.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AircraftNANA257.0NANANA331.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:AirportFacilitiesNANA9.0NANANA11.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CPAAircraftNANA261.0NANANA329.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease alk:CorporaterealestateNANA78.0NANANA74.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:StockholdersEquity ▆▄▅▆▇▇██▇▇▇▇▆▆▇▆▅▅▅▄▄▃▃▃▃▃▃▃▃▃▂▂▁▁▁3324.02875.02988.03454.03861.04015.04331.04252.03973.03746.03751.03791.03593.03439.03721.03491.03264.03014.02931.02864.02627.02455.02411.02365.02219.02166.02127.02229.02200.02095.02029.01802.01543.01462.01421.0NA1283.01218.01173.21264.31206.51170.11105.4NANANA
us-gaap:CommonStockValue ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁█████████▅▅▅▅▅1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.069.069.070.070.070.070.070.270.771.237.937.837.737.437.0NANANA
us-gaap:AdditionalPaidInCapitalCommonStock ▅▄▄▄▄▃▃▃▃▃▃▂▂▂▂▂▂▂▁▁▁▁▁▁▁▂▃▄▅▅▅▆▆▆▆▆▆▇█████454.0409.0391.0366.0350.0314.0305.0297.0270.0261.0232.0224.0198.0190.0164.0156.0135.0126.0110.0103.091.086.073.070.056.0211.0296.0399.0551.0524.0538.0625.0629.0657.0660.0660.3674.2677.8840.0843.3838.9828.3815.5NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▆▆▆▇▇███▇▇▇▇▇▇▇▆▆▆▆▅▅▅▅▄▄▄▃▃▃▃▃▂▂▂▂▂▂▁▁▁▁▁▁4030.03633.03764.04211.04642.04856.05133.04996.04717.04498.04534.04550.04373.04219.04454.04117.03888.03629.03568.03488.03266.03039.02890.02724.02474.02266.02144.02012.01831.01684.01607.01542.01268.01164.01127.01082.3918.9851.4810.6746.6669.1640.3566.1NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▁▁▁▂▂▁▂▃▃▂▂▂▂▂▄▆▅▅▅▆▆▅▅▅▅▅▅████▃▃▂▂▄▄▃▃▆▆▆▆-487.0-494.0-494.0-450.0-458.0-482.0-465.0-421.0-422.0-433.0-448.0-428.0-435.0-440.0-380.0-289.0-294.0-299.0-305.0-284.0-287.0-294.0-303.0-303.0-304.0-305.0-310.0-178.0-178.0-181.0-183.0-414.0-424.0-429.0-436.0-373.6-380.8-382.4-390.0-256.0-260.0-263.7-267.2NANANA
 us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:BalanceSheetLocation,us-gaap:DerivativeInstrumentRisk,us-gaap:HedgingDesignation alk:AccumulatedOtherComprehensiveIncomeLossBalanceSheetLocation,us-gaap:InterestRateSwap,us-gaap:DesignatedAsHedgingInstrumentNANA-21.0NANANA-13.0NANANA-1.0NANANA-2.0NANANA5.0NANANA18.0-22.0-19.0-21.019.0-17.0-19.0-18.017.0-19.0-20.0-29.033.034.132.0NA28.8NANANANANANANA
us-gaap:TreasuryStockValue ███████▇▇▇▇▇▇▇▆▆▆▆▆▆▆▅▄▂▁▁▁▁▁▁▁▁674.0674.0674.0674.0674.0674.0643.0621.0593.0581.0568.0556.0544.0531.0518.0494.0466.0443.0443.0444.0444.0377.0250.0127.08.07.04.05.05.01.02.021.0NANA0.00.00.00.0125.3107.479.272.246.0NANANA
us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue █▁13.012.0NA7.02.09.0NA7.09.012.0NA8.09.012.0NANANANANANANANANANANANANANANANANANANANANANANANA21.1-2.2-2.7-4.6-3.1-1.9-3.7-5.0
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities █▄▁▂▅▃▅▅▆▆▄▅▆▅▄▅▇▆▄▅▅▆▅▅▅▆▄▅▅▄▄▄▅▄▄▄▅▄▄▄▅▄▃▄▅▃840.0167.0-350.0-205.0288.033.0341.0348.0565.0468.0209.0260.0420.0306.0233.0273.0614.0470.0180.0307.0374.0525.0355.0340.0375.0514.0138.0257.0393.0242.0159.0230.0380.0212.0115.7181.6272.4183.387.2240.1249.9118.847.3172.8279.154.5
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆█▅▇▇▇▇▆▇▆█▆▇▇▇▆▆▁▇▇▆▇▇▇▆█▇▆▇▇▇▆▇▇▇▇▇█▇▇▇▇▇▇▇-527.0-543.0174.0-643.03.0-127.0-83.0-178.0-344.0-186.0-298.0135.0-304.0-164.010.0-171.0-483.0-488.0-1981.0-51.0-254.0-336.0-203.0-133.0-173.0-421.077.0-36.0-418.0-164.0-18.0-168.0-361.0-151.0-131.5-102.8-237.3-173.435.3-196.7-208.1-33.83.8-59.1-192.0-47.9
us-gaap:NetCashProvidedByUsedInFinancingActivities ▁▃▁▇▄▅▁▂▂▂▂▁▂▂▂▂▂▂▄█▂▂▂▂▂▂▂▂▂▂▂▂▂▂▃▂▂▂▂▂▂▂▂▂▂▂-363.082.0-305.01195.0407.0684.0-275.0-175.0-192.0-171.019.0-319.0-191.0-156.0-193.0-156.0-116.0-127.0311.01481.0-117.0-184.0-167.0-164.0-208.0-149.0-142.0-209.0-43.0-68.0-102.0-78.0-57.0-88.0110.5-86.7-47.9-63.9-87.8-42.9-35.0-114.3-90.8-92.6-96.7-53.1
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect █▁-50.0-294.0NA347.0698.0590.0NA-5.029.0111.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:DepreciationDepletionAndAmortization ▇▇▇████████▇▇▆▇▆▆▆▄▇▆▅▅▄▄▄▄▄▃▃▂▂▃▃▃▂▂▂▂▂▂▂▁▁▁▁98.097.0100.0105.0107.0108.0106.0106.0105.0106.0108.099.097.094.097.095.090.090.082.0101.092.088.084.081.079.076.076.075.073.070.067.067.068.069.068.665.965.863.762.762.261.760.358.557.858.056.2
us-gaap:NetCashProvidedByUsedInOperatingActivities █▄▁▂▅▃▅▅▆▆▄▅▆▅▄▅▇▆▄▅▅▆▅▅▅▆▄▅▅▄▄▄▅▄▄▄▅▄▄▄▅▄▃▄▅▃840.0167.0-350.0-205.0288.033.0341.0348.0565.0468.0209.0260.0420.0306.0233.0273.0614.0470.0180.0307.0374.0525.0355.0340.0375.0514.0138.0257.0393.0242.0159.0230.0380.0212.0115.7181.6272.4183.387.2240.1249.9118.847.3172.8279.154.5
us-gaap:NetIncomeLoss █▄▁▁▃▃▆▇▇▅▅▇▆▅█▇▇▆▆▇▇▆▆▇▇▆▆▆▆▅▅▇▆▅▅▆▅▅▅▅▅▅▅▆▅▅397.0-131.0-447.0-431.0-214.0-232.0181.0322.0262.04.023.0217.0193.04.0373.0266.0296.099.0114.0256.0260.0184.0191.0274.0234.0149.0148.0198.0165.094.078.0289.0104.037.044.3163.467.540.864.077.528.874.264.8122.458.65.3
us-gaap:ShareBasedCompensation ▇▇▇▆▄▆▆▅▆▇▇█▆▆▇█▇▇▆▆▅▆▅▆▆▆▁▆█▅▆▆▅▇▅▅▅▆▆▅▅▆12.012.010.07.0-2.09.09.04.05.011.013.017.09.08.012.018.012.013.07.06.04.09.03.08.05.09.0-21.06.017.04.06.09.03.014.02.22.30.25.37.02.20.66.7NANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▆▆█▅▇▇▇▇▆▇▆█▆▇▇▇▆▆▁▇▇▆▇▇▇▆█▇▆▇▇▇▆▇▇▇▇▇█▇▇▇▇▇▇▇-527.0-543.0174.0-643.03.0-127.0-83.0-178.0-344.0-186.0-298.0135.0-304.0-164.010.0-171.0-483.0-488.0-1981.0-51.0-254.0-336.0-203.0-133.0-173.0-421.077.0-36.0-418.0-164.0-18.0-168.0-361.0-151.0-131.5-102.8-237.3-173.435.3-196.7-208.1-33.83.8-59.1-192.0-47.9
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▂▁▁▂▂▃▄▄▅▃█▃▄▅▄▇▆▅▄▄▅▃▄▃▆▆▃▅▅▃▄▃▄▃▄▂▄▃▃▂▃▄▁▂▂▁75.027.02.036.049.0119.0169.0194.0218.0115.0406.0131.0188.0235.0185.0329.0296.0216.0169.0169.0221.0119.0163.0109.0280.0279.0135.0209.0257.093.0171.0137.0155.0103.0178.384.9156.798.192.953.492.0149.129.142.185.925.9
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▁▃▁▇▄▅▁▂▂▂▂▁▂▂▂▂▂▂▄█▂▂▂▂▂▂▂▂▂▂▂▂▂▂▃▂▂▂▂▂▂▂▂▂▂▂-363.082.0-305.01195.0407.0684.0-275.0-175.0-192.0-171.019.0-319.0-191.0-156.0-193.0-156.0-116.0-127.0311.01481.0-117.0-184.0-167.0-164.0-208.0-149.0-142.0-209.0-43.0-68.0-102.0-78.0-57.0-88.0110.5-86.7-47.9-63.9-87.8-42.9-35.0-114.3-90.8-92.6-96.7-53.1
 us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:DebtInstrument alk:PSPNotesPayableThrough2031NA136.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:DebtInstrument alk:Variableratenotespayableduethrough2029Member▁█0.054.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:RepaymentsOfLongTermDebt █▂▅▂▂▂▅▄▃▆▄▄▃▂▂▂▁▂▃▁▁▁▁▁▁▁▁▁▁▁▁▁▁▂▁▂▂▁▂▂▁▂▂▂▂▁566.0115.0327.0113.065.060.0306.0220.0139.0393.0263.0286.0138.0120.0132.0106.058.0101.0156.036.021.036.023.035.023.035.022.033.027.037.022.030.021.088.035.174.5106.359.185.2122.936.289.289.7100.491.139.8
us-gaap:PaymentsOfDividends NANA0.00.00.045.044.043.043.043.040.039.040.039.037.037.037.037.034.034.034.034.024.026.026.026.017.017.017.017.014.014.00.00.00.0NANANANANANANANANANANA
us-gaap:PaymentsForRepurchaseOfCommonStock NANA0.00.00.031.022.028.012.013.013.012.013.012.025.028.022.00.00.00.066.0127.0124.0119.0160.0102.0106.0159.053.030.076.032.032.019.08.325.417.58.817.928.37.026.313.94.915.810.5
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31

Common Stock Value

us-gaap:CommonStockValue

us-gaap:CommonStockValue


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.0696970707070707071373737373735
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 Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.11.21.21.21.21.31.31.31.30.70.70.70.70.70.7

Common Stock Par Or Stated Value Per Share

us-gaap:CommonStockParOrStatedValuePerShare

us-gaap:CommonStockParOrStatedValuePerShare


Common
Period End2021-06-302021-03-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-03-312010-12-312009-12-31
Value0.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.011.01.01.01.01.01.01.01.01.01.01.01.01.0
Percentage of CommonStockParOrStatedValuePerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Preferred Stock Par Or Stated Value Per Share

us-gaap:PreferredStockParOrStatedValuePerShare

us-gaap:PreferredStockParOrStatedValuePerShare


Preferred
Period End2021-06-302021-03-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-03-312010-12-312009-12-31
Value0.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.010.011.01.01.01.01.01.01.01.01.01.01.01.01.0
Percentage of PreferredStockParOrStatedValuePerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


Common
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-03-312010-12-312009-12-31
Value13413313313213113113113113113013013013012912912912912912912812812812812813013113313668686970707070707137373735
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

us-gaap:CommonStockSharesAuthorized

us-gaap:CommonStockSharesAuthorized


Common
Period End2021-06-302021-03-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-03-312010-12-312009-12-31
Value400400400400400400400400400400400400400400200200200200200200200200200200200200100100100100100100100100100100100100100
Percentage of CommonStockSharesAuthorized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Outstanding

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


Common
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-312012-06-302012-03-312011-12-31
Value12512412412312212312312312312312312312312312312312312312312312312512612813013113313668686970707135
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockSharesOutstanding us-gaap:StatementEquityComponents

us-gaap:CommonStock


Common
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value0.0001252290.0001244421240.0001236610.000123638999999999990.0001225851230.0001232780.0001233380.0001235041230.0001233610.0001232040.0001233512312312513168703535363535353638
Percentage of CommonStockSharesOutstanding0.00.0100.00.00.00.0100.00.00.00.0100.00.00.00.0100.0100.0100.0100.0100.0100.099.90.00.00.00.00.00.00.0

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
Value12612412312312412412412312312412312412412412312312512813013213613869707171717272363636363636
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
Value12412412312312212312312312312312312312312312312312412712913113413768697070707071353535353535
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 End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.18-1.05-3.6-3.49-1.74-1.891.482.612.120.030.191.761.570.033.042.152.40.80.932.082.111.471.532.151.81.131.121.471.21.371.144.131.490.520.642.30.950.571.792.150.82.061.83.411.640.15
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3.13-1.05-3.6-3.49-1.73-1.871.452.62.110.030.181.751.560.033.042.142.380.790.912.072.11.461.512.141.791.121.111.451.191.351.124.081.470.510.632.270.930.561.752.120.782.011.753.321.60.15
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value404-131.0-491.0-423.0-190.0-249.0137323273193.02241986.028327030110593259267193191275235154161981689630929910944-18.11706948-69.7813277
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues26.5-16.4-60.8-60.3-45.1-15.26.113.511.91.00.110.19.20.3-4.812.814.36.0-2.116.517.914.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.04.72.16.82.98.1

Costs And Expenses

us-gaap:CostsAndExpenses

us-gaap:CostsAndExpenses


Costs
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302017-06-30
Value978958-3895.012727091957-5534.0196719241851515758556166
Percentage of CostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues64.0120.2-482.1181.5168.4119.6-248.482.384.198.72.52.62.7-0.92.93.1

us-gaap:CostsAndExpenses us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value122910071785196219131829
Percentage of CostsAndExpenses96.6142.091.299.799.498.8
Percentage of Revenues175.3239.2109.182.183.697.5
Percentage of Revenues alk:AirGroupAdjusted175.3239.2109.182.183.697.5

alk:AlaskaMainline


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value9627911472163715891510
Percentage of CostsAndExpenses75.6111.675.283.282.681.6
Percentage of Revenues137.2187.990.068.569.480.5
Percentage of Revenues alk:AlaskaMainline188.3247.2107.081.282.496.2

alk:AlaskaRegional


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value286230331350345340
Percentage of CostsAndExpenses22.532.416.917.817.918.4
Percentage of Revenues40.854.620.214.715.118.1
Percentage of Revenues alk:AlaskaRegional150.5227.7128.393.896.6111.5

alk:Horizon


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value786892949597
Percentage of CostsAndExpenses6.19.64.74.84.95.2
Percentage of Revenues11.116.25.63.94.25.2
Percentage of Revenues alk:Horizon82.184.087.683.984.882.9

alk:SpecialRevenueandCharges


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value43-298.01725.01122
Percentage of CostsAndExpenses3.4-42.08.80.30.61.2
Percentage of Revenues6.1-70.810.50.20.51.2
Percentage of Revenues alk:SpecialRevenueandCharges0.00.00.00.00.00.0

us-gaap:IntersegmentElimination


Costs
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-97.0-82.0-110.0-119.0-116.0-118.0
Percentage of CostsAndExpenses-7.6-11.6-5.6-6.0-6.0-6.4
Percentage of Revenues-13.8-19.5-6.7-5.0-5.1-6.3
Percentage of Revenues us-gaap:IntersegmentElimination102.1101.2106.8107.2105.5101.7

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

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value528-173.0-643.0-589.0-291.0-317.02434163516.0362842596.0149427479152231402420292259437376240242316265152125463169597226510966100125471201031989410
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues34.6-21.7-79.6-84.0-69.1-19.410.917.415.30.31.712.812.00.3-2.520.222.88.7-5.225.728.121.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.06.4-3.110.54.212.510.818.69.61.2

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-48.0-577.0-471.0-546.0-589.0-145.024342136228128311276241654465052023084274242902924423702402063202521441242511707182244178465721114448
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-9.1333.573.392.7202.445.7100.0101.2103.1466.7355.6109.5106.6400.0110.7104.4105.4132.9133.3106.2101.099.3112.7101.198.4100.085.1101.395.194.799.254.2100.6120.3113.192.0163.870.157.2168.9307.940.4
Percentage of Revenues-3.1-72.4-58.3-77.9-139.9-8.910.917.615.81.56.214.112.81.3-2.821.124.011.5-7.027.328.421.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.04.5-1.817.713.05.1
Percentage of Revenues alk:AirGroupAdjusted0.00.00.0-77.9-139.9-8.90.017.615.81.50.014.112.81.30.021.124.011.50.027.328.421.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.04.50.017.713.05.1

alk:AlaskaMainline


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-24.0-444.0-370.0-463.0-471.0-85.023237833449138314288691854224902152883833922782623863312281832822311381022151506366210155334017112240
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-4.5256.657.578.6161.926.895.590.995.2816.7383.3110.6111.21150.0124.298.8102.3141.4124.795.393.395.2101.288.388.095.075.689.287.290.881.646.488.8106.891.579.3142.550.040.5136.6260.433.4
Percentage of Revenues-1.6-55.7-45.8-66.0-111.9-5.210.415.814.62.66.714.213.43.8-3.120.023.312.3-6.524.526.220.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.2-1.214.311.04.2
Percentage of Revenues alk:AlaskaMainline0.00.00.0-90.6-147.2-6.20.018.817.33.10.016.715.54.40.023.226.914.20.029.631.524.80.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.90.017.413.45.1

alk:AlaskaRegional


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-56.0-150.0-123.0-96.0-129.0-73.02.02312-35.0-18.0-13.0-20.0-49.0-25.02026-6.0213524132345297.02029214.01930154.01025196.61234156.5
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-10.686.719.116.344.323.00.85.53.4-583.3-50.0-4.6-7.7-816.7-16.84.75.4-3.99.18.75.74.58.910.37.72.98.39.27.92.615.26.58.96.815.09.517.79.912.127.833.85.4
Percentage of Revenues-3.7-18.8-15.2-13.7-30.6-4.50.11.00.5-1.9-0.9-0.6-0.9-2.70.40.91.2-0.3-0.52.21.61.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.6-0.42.91.40.7
Percentage of Revenues alk:AlaskaRegional0.00.00.0-50.5-127.7-28.30.06.23.4-11.50.0-4.0-6.8-19.40.06.99.4-2.60.012.99.75.80.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.50.016.28.13.7

alk:ConsolidatingAndOther


Income
Period End2021-06-302021-03-312020-06-302020-03-31
Value176.03.05.0
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments3.2-3.5-1.0-1.6
Percentage of Revenues1.10.80.70.3
Percentage of Revenues alk:ConsolidatingAndOther0.00.00.00.0

alk:Horizon


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
Value151114118.08.05.01110.0127.07.010.03.03.05.0-9.0-7.00.09.07.0-2.04.010.08.06.03.0110.03.04.06.06.04.04.88.04.27.0444.4-19.42.91811-1.2
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments2.8-6.4-2.2-1.9-2.7-2.52.12.62.8200.019.42.53.950.02.01.2-1.9-4.60.02.21.7-0.71.52.32.12.51.23.50.02.03.21.33.66.86.63.03.810.543.73.5-41.32.417.95.9-1.3
Percentage of Revenues1.01.41.71.61.90.50.20.50.40.60.30.30.50.2-0.10.2-0.4-0.4-0.00.60.5-0.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.7-1.30.4-1.70.31.91.1-0.1
Percentage of Revenues alk:Horizon0.00.00.011.69.97.60.09.88.910.30.05.47.22.70.04.4-8.3-7.10.08.26.3-1.90.09.58.16.10.011.10.03.30.06.86.64.30.08.34.77.90.04.7-20.33.00.06.5-0.7

alk:SpecialCharges


Income
Period End2021-06-302021-03-312020-06-302020-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value576404298-172.0-1.0-12.0-9.521-69.61943-86.3-97.771
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments109.1-233.5-102.454.3-0.6-20.3-13.18.0-63.829.942.8-68.9-207.959.6
Percentage of Revenues37.750.770.8-10.50.00.00.00.00.01.9-1.3-7.2-8.87.4
Percentage of Revenues alk:SpecialCharges0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:SpecialRevenueandCharges


Income
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-30
Value-43.0298-172.0-5.0-11.0-22.0-27.0-17.0-18.0-19.0-26.0-50.0-25.0-4.02.0-5.06.00.0-4.0138.0212-1.0-12.021
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments7.3-102.454.3-1.2-3.1-366.7-9.5-6.6-300.0-4.4-5.4-32.9-6.2-1.00.7-1.11.60.0-1.34.95.345.8-0.6-20.37.9
Percentage of Revenues-6.170.8-10.5-0.2-0.5-1.2-1.2-0.8-1.0-0.9-1.2-2.9-1.6-0.30.10.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues alk:SpecialRevenueandCharges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination


Income
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value2.03.05.04.09.06.02.01.03.0-2.01.02.0-1.0-2.00.0-1.00.01.01.03.01.02.0-1.00.0-2.00.0-1.0-1.00.0-1.00.00.00.5-0.3-0.2-0.5-0.7-1.0-0.9
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-0.3-1.0-1.61.62.21.733.32.81.1-0.816.71.3-0.2-0.40.0-0.40.00.20.31.20.20.5-0.40.0-0.60.0-0.7-0.80.0-0.60.00.00.2-0.3-0.3-0.5-0.6-2.1-0.7
Percentage of Revenues0.30.70.30.20.40.30.10.00.1-0.10.1-0.0-0.0-0.10.00.00.00.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.00.0-0.1-0.1-0.1
Percentage of Revenues us-gaap:IntersegmentElimination-2.1-3.7-4.90.0-8.1-5.5-1.70.0-2.31.5-0.90.00.91.9-0.00.0-0.0-0.9-1.00.0-1.0-2.01.00.02.0-0.01.10.0-0.01.1-0.00.0-0.50.30.20.00.81.11.0

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
Value131-42.0-196.0-158.0-77.0-85.06294892.01367662.0-224.01611835311714616010868163142919411810058471746522281024125364718463875354.9
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 Revenues8.6-5.3-24.3-22.5-18.3-5.22.83.93.90.10.63.03.10.13.87.68.73.0-2.79.310.78.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.02.5-1.14.01.64.84.07.13.60.6

Interest Expense

us-gaap:InterestExpense

us-gaap:InterestExpense


Interest
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value3932171318182022202225242626262522119.01310.010.011111212121214131416151517161825202326292625
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.64.04.00.80.80.80.91.21.01.01.21.3-0.41.21.21.4-0.50.70.61.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.6-0.62.11.82.42.82.82.73.1

us-gaap:InterestExpense us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Interest
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value3932171318182022202225242626262522119.01310.010.0111112121212141314161515171618252023
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues2.64.04.00.80.80.80.91.21.01.01.21.3-0.41.21.21.4-0.50.70.61.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.6-0.62.11.82.4
Percentage of Revenues alk:AirGroupAdjusted0.00.04.00.80.00.80.91.20.01.01.21.30.01.21.21.40.00.70.61.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.60.02.11.82.4

alk:AlaskaMainline


Interest
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value34271812181819211820222224232322197.04.0127.07.07.07.07.08.09.08.08.09.09.0111011121214211619
Percentage of InterestExpense87.284.4105.992.3100.0100.095.095.590.090.988.091.792.388.588.588.086.463.644.492.370.070.063.663.658.366.775.066.757.169.264.368.868.974.873.875.979.184.881.584.2
Percentage of Revenues2.23.44.30.70.80.80.81.10.90.91.01.2-0.41.11.11.3-0.40.40.30.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.2-0.41.81.52.0
Percentage of Revenues alk:AlaskaMainline0.00.05.60.90.00.91.01.30.01.11.21.40.01.31.31.50.00.50.31.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.50.02.21.82.5

alk:Horizon


Interest
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value5.05.05.05.06.07.07.08.06.06.05.05.04.04.03.02.02.02.04.01.02.03.01.04.02.04.02.04.04.04.04.03.03.94.04.14.04.14.04.44.7
Percentage of InterestExpense12.815.629.438.533.338.935.036.430.027.320.020.815.415.411.58.09.118.244.47.720.030.09.136.416.733.316.733.328.630.828.618.825.826.523.824.122.515.622.020.1
Percentage of Revenues0.30.61.20.30.30.30.30.40.30.30.20.3-0.10.20.10.1-0.00.10.30.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.4-0.10.30.40.5
Percentage of Revenues alk:Horizon0.00.06.24.80.06.26.26.80.04.63.64.50.03.52.82.00.01.83.61.00.02.91.04.00.04.02.34.40.04.54.43.20.04.24.64.50.04.34.64.8

Interest Paid Net

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11501213169.0121416181221152416261626124.00.08.0-1.01.01.07.02.010.05.0114.010.06.0155.8159.0157.626142526311828
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.76.31.51.93.80.60.50.60.71.00.60.90.71.3-0.31.20.81.5-0.30.30.00.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.5-0.22.21.32.62.83.01.93.4

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value397-131.0-447.0-431.0-214.0-232.01813222624.0232171934.0373266296991142562601841912742341491481981659478289104374416367406477287464122585.3
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues26.0-16.4-55.3-61.5-50.8-14.28.113.511.50.21.19.89.00.2-6.312.614.15.7-2.616.317.413.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.9-2.06.52.67.76.811.56.00.6

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value397-131.0-431.0-214.0-232.03222624.02171934.064772874
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues26.0-16.4-61.5-50.8-14.213.511.50.29.89.00.2-2.06.52.67.7
Percentage of Revenues us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-21.0-12.0-48.0-18.0-3.04.0-9.0-6.0-13.0-19.0-10.0-13.0-12.0-23.0-13.0-12.0-14.0-14.0-10.02.02.02.04.04.04.02.00.00.02.011-5.0-7.0-5.0-5.0-1.6-3.9-6.7-5.8-13.4-17.9-10.8-13.1-15.8-18.7-15.7-15.5
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-1.4-1.5-5.9-2.6-0.70.2-0.4-0.3-0.6-1.0-0.5-0.6-0.6-1.30.2-0.6-0.7-0.80.20.10.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.60.4-1.5-1.0-1.4-1.6-1.8-1.6-1.9

us-gaap:NonoperatingIncomeExpense us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-21.0-12.0-22.0-18.0-3.04.0-9.0-6.0-13.0-19.0-10.0-13.0-12.0-23.0-13.0-12.0-14.0-14.0-10.02.02.02.04.04.04.02.00.00.02.011-5.0-7.0-5.0-5.0-1.6-3.9-6.7-5.8-13.4-17.9-10.8-13.1
Percentage of NonoperatingIncomeExpense100.0100.045.8100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-1.4-1.5-2.7-2.6-0.70.2-0.4-0.3-0.6-1.0-0.5-0.6-0.6-1.30.2-0.6-0.7-0.80.20.10.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.60.4-1.5-1.0-1.4
Percentage of Revenues alk:AirGroupAdjusted0.00.00.0-2.6-0.70.20.0-0.3-0.6-1.00.0-0.6-0.6-1.30.0-0.6-0.7-0.80.00.10.10.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.60.0-1.5-1.0-1.4

alk:AlaskaMainline


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-16.0-7.0-18.0-12.00.011-4.00.0-6.0-11.0-3.0-6.0-4.0-12.0-9.0-7.0-11.0-12.0-8.05.05.01.04.05.05.05.03.04.05.0152.04.01.0-1.01.7-0.1-3.2-2.4-10.0-13.8-6.9-8.9
Percentage of NonoperatingIncomeExpense76.258.337.566.7-0.0275.044.4-0.046.257.930.046.233.352.269.258.378.685.780.0250.0250.050.0100.0125.0125.0250.00.00.0250.0136.4-40.0-57.1-20.020.0-106.22.647.841.474.677.163.967.9
Percentage of Revenues-1.0-0.9-2.2-1.70.00.7-0.20.0-0.3-0.6-0.1-0.3-0.2-0.70.2-0.3-0.5-0.70.20.30.30.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.20.3-1.2-0.6-0.9
Percentage of Revenues alk:AlaskaMainline0.00.00.0-2.30.00.80.00.0-0.3-0.70.0-0.3-0.2-0.80.0-0.4-0.6-0.80.00.40.40.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.30.0-1.4-0.8-1.1

alk:Horizon


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-5.0-5.0-6.0-6.0-5.0-5.0-6.0-7.0-7.0-8.0-6.0-5.0-5.0-4.0-3.0-4.0-2.0-2.0-1.0-2.0-3.0-1.0-1.0-3.0-2.0-3.00.0-4.0-3.0-3.0-3.0-3.0-3.0-3.0-3.0-3.7-3.7-3.6-3.5-3.9-4.2-3.9-3.3-4.1-4.8
Percentage of NonoperatingIncomeExpense23.841.712.533.3166.7-125.066.7116.753.842.160.038.541.717.423.133.314.314.310.0-100.0-150.0-50.0-25.0-75.0-50.0-150.00.00.0-150.0-27.360.042.960.060.0187.594.955.262.126.121.838.929.820.921.930.6
Percentage of Revenues-0.3-0.6-0.7-0.9-1.2-0.3-0.3-0.3-0.3-0.4-0.3-0.2-0.2-0.20.1-0.2-0.1-0.10.0-0.1-0.2-0.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-0.30.1-0.3-0.4-0.4-0.3-0.4-0.5
Percentage of Revenues alk:Horizon0.00.00.0-6.3-6.2-4.80.0-6.2-6.2-6.80.0-3.8-3.6-3.60.0-3.5-1.8-2.00.0-1.8-2.7-1.00.0-2.9-2.0-3.00.0-4.0-3.4-3.30.0-3.4-3.3-3.20.0-3.9-4.2-4.00.0-4.2-4.4-4.00.0-2.3-2.8

Operating Expenses

us-gaap:OperatingExpenses

us-gaap:OperatingExpenses


Operating
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value9789587091957197619671924185120181915188518031800168116091583128311661076105711221082106510311064114911121081108010871082106910581002109796693010541052831839851866803
Percentage of OperatingExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues64.0120.2168.4119.688.782.384.198.797.886.687.498.4-30.279.776.590.5-29.174.572.078.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.093.0-28.488.094.886.187.679.788.896.9

us-gaap:OperatingExpenses us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Operating
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value15541362100717851976196219131829192618881868178517841662158315331206114110721059108910771071103111001145112510891081110710811057104810231027986973968954903
Percentage of OperatingExpenses158.9142.2142.091.2100.099.799.498.895.498.699.199.099.198.998.496.894.097.999.6100.297.199.5100.6100.0103.499.7101.2100.7100.1101.899.998.999.1102.193.7102.1104.691.890.7108.6
Percentage of Revenues101.8170.9239.2109.188.782.183.697.593.385.486.697.4-30.078.875.387.7-27.472.971.878.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.094.9-29.780.886.093.6
Percentage of Revenues alk:AirGroupAdjusted0.00.0239.2109.10.082.183.697.50.085.486.697.40.078.875.387.70.072.971.878.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.094.90.080.886.093.6

alk:AlaskaMainline


Operating
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value123710677911472163116371589151016001564156714981514140513301290983915859845884872877842905943926894896925896870862843848814800796783736
Percentage of OperatingExpenses126.5111.4111.675.282.583.282.681.679.381.783.183.184.183.682.781.576.678.579.879.978.880.682.381.785.182.183.382.783.085.182.881.481.584.177.484.286.075.574.588.5
Percentage of Revenues81.0133.9187.990.073.268.569.480.577.570.772.781.8-25.466.663.373.8-22.358.457.562.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.078.3-24.566.570.676.3
Percentage of Revenues alk:AlaskaMainline0.00.0247.2107.00.081.282.496.20.083.084.394.90.077.273.085.00.070.868.975.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.095.80.081.285.893.7

alk:AlaskaRegional


Operating
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value352317230331357350345340341337314294278264245236224236223211211216204196200214200199191190193193192190184181179179179171
Percentage of OperatingExpenses36.033.132.416.918.117.817.918.416.917.616.716.315.415.715.214.917.520.220.720.018.820.019.219.018.818.618.018.417.717.517.818.118.219.016.818.719.217.117.120.6
Percentage of Revenues23.139.854.620.216.014.715.118.116.515.214.616.0-4.712.511.713.5-5.115.114.915.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.017.4-5.515.016.217.7
Percentage of Revenues alk:AlaskaRegional0.00.0227.7128.30.093.896.6111.50.0103.4106.1116.70.091.388.1102.60.087.190.394.20.00.00.00.00.00.00.00.00.00.00.00.00.00.00.096.50.083.891.996.3

alk:ConsolidatingAndOther


Operating
Period End2021-06-302021-03-312020-06-302020-03-31
Value-126.0-110.0-82.0-110.0
Percentage of OperatingExpenses-12.9-11.5-11.6-5.6
Percentage of Revenues-8.3-13.8-19.5-6.7
Percentage of Revenues alk:ConsolidatingAndOther0.00.00.00.0

alk:Horizon


Operating
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value918868929994959712011812310410310511610310299101105101939091928586868880848990868378448411090147165167
Percentage of OperatingExpenses9.39.29.64.75.04.84.95.25.96.26.55.85.76.27.26.58.08.59.49.99.08.68.58.88.67.47.78.08.17.47.88.38.58.67.68.14.88.010.510.817.619.419.3
Percentage of Revenues6.011.016.25.64.43.94.25.25.85.35.75.7-1.75.05.55.9-2.36.36.87.80.00.00.00.00.00.00.00.00.00.00.00.00.00.00.07.5-1.47.110.09.315.415.517.2
Percentage of Revenues alk:Horizon0.00.084.087.60.083.984.882.90.090.889.193.70.092.9106.4105.10.090.091.0101.00.088.690.991.90.085.998.994.50.090.992.394.70.089.893.488.10.091.1115.993.00.091.397.9

alk:SpecialCharges


Operating
Period End2021-06-302021-03-312020-06-302020-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-576.0-404.0-298.01721.0129.5-21.269-19.9-43.18697-71.9
Percentage of OperatingExpenses-58.9-42.2-42.08.80.11.10.9-2.16.3-2.1-4.68.29.3-8.6
Percentage of Revenues-37.7-50.7-70.810.50.00.00.00.00.0-1.91.37.28.8-7.4
Percentage of Revenues alk:SpecialCharges0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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
Value549-161.0-595.0-571.0-288.0-321.02524223642546297271291624394931662414004182902554333722382423162631411304701746474269115721141435713311921610925
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 Revenues36.0-20.2-73.6-81.5-68.4-19.611.317.715.91.32.213.412.61.6-2.720.823.59.5-5.525.528.021.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.07.0-3.512.05.213.912.420.311.23.1

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-06-302020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value7.0-44.08.024-17.0-44.01.01115-20.07.05.02.0-90.04.05.06.0-21.03.07.09.00.01.01.05.0-132.00.03.02.023110.05.07.0-62.47.21.67.0-134.24.03.7
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.5-5.41.15.7-1.0-2.00.00.50.8-1.00.30.20.11.50.20.20.30.50.20.50.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.74.10.30.3

us-gaap:OtherComprehensiveIncomeLossNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Other
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value7.08.024-17.01.011157.05.02.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.51.15.7-1.00.00.50.80.30.20.1
Percentage of Revenues us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.0

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
Value9.010.01.05.06.05.0-6.0-3.0-7.0-10.0-3.0-7.0-1.0-12.00.00.0-1.00.01.00.0-3.01.00.00.01.00.00.02.05.013-1.0-5.00.02.03.42.31.91.4-5.71.21.30.92.91.81.30.9
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.00.0100.00.0100.0100.00.00.0100.00.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues0.61.30.10.71.40.3-0.3-0.1-0.3-0.5-0.1-0.3-0.0-0.7-0.00.0-0.00.0-0.00.0-0.20.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.20.10.10.10.30.20.10.1

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ContractWithCustomerSalesChannel

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

alk:CargoandOtherRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value5744434539465260595052555141424748
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues3.75.55.36.49.32.82.32.52.62.72.52.52.42.2-0.72.22.3
Percentage of Revenues alk:CargoandOtherRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value272178182148129261312304290263265267275246240239252
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax477.2404.5423.3328.9330.8567.4600.0506.7491.5526.0509.6485.5539.2600.0571.4508.5525.0
Percentage of Revenues17.822.322.521.130.616.014.012.712.714.012.812.112.813.4-4.011.312.0
Percentage of Revenues alk:MileagePlanRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:PassengerRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1352659657572309148120572211211117161907204319971684179619581945
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2371.91497.71527.91271.1792.33219.63955.83685.03578.03432.03667.33714.53915.74107.34276.24166.04052.1
Percentage of Revenues88.582.781.381.673.490.592.392.592.391.592.492.492.691.9-30.292.892.5
Percentage of Revenues alk:PassengerRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService, us-gaap:ContractWithCustomerSalesChannel

alk:CargoServices, alk:CargoandOtherRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value3427293128242936383032363426273232
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax59.661.467.468.971.852.255.860.064.460.061.565.566.763.464.368.166.7
Percentage of Revenues2.23.43.64.46.71.51.31.51.71.61.61.61.61.4-0.51.51.5
Percentage of Revenues alk:CargoServices alk:CargoandOtherRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanServices, alk:PassengerRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value15484746456152193186172153160153167139136134143
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax270.2190.9172.1142.2143.6330.4371.2310.0291.5306.0307.7278.2327.5339.0323.8285.1297.9
Percentage of Revenues10.110.59.29.113.39.38.77.87.58.27.86.97.77.6-2.36.46.8
Percentage of Revenues alk:MileagePlanServices alk:PassengerRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanServicesOther, alk:MileagePlanRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value118941088473109119118118110105114108107104105109
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax207.0213.6251.2186.7187.2237.0228.8196.7200.0220.0201.9207.3211.8261.0247.6223.4227.1
Percentage of Revenues7.711.813.412.017.36.75.34.95.25.95.15.25.05.8-1.75.05.2
Percentage of Revenues alk:MileagePlanServicesOther alk:MileagePlanRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:OtherServices, alk:CargoandOtherRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value2317141411222324212020191715151516
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax40.438.632.631.128.247.844.240.035.640.038.534.533.336.635.731.933.3
Percentage of Revenues1.52.11.72.02.61.31.01.00.91.11.00.90.80.8-0.30.70.8
Percentage of Revenues alk:OtherServices alk:CargoandOtherRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:PassengerAncillaryServices, alk:PassengerRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value8450494931116139157147124129146137117123141134
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax147.4113.6114.0108.979.5252.2267.3261.7249.2248.0248.1265.5268.6285.4292.9300.0279.2
Percentage of Revenues5.56.36.17.07.47.16.26.66.46.66.26.66.46.4-2.16.76.4
Percentage of Revenues alk:PassengerAncillaryServices alk:PassengerRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:PassengerTickets, alk:MileagePlanRevenue


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value1548456152
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax270.2190.9143.6330.4
Percentage of Revenues10.110.513.39.3
Percentage of Revenues alk:PassengerTickets alk:MileagePlanRevenue0.00.00.00.0

alk:PassengerTickets, alk:PassengerRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1114525534459222121317251868179214391618174416931428153716831668
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1954.41193.21241.91020.0569.22637.03317.33113.33037.32878.03111.53170.93319.63482.93659.53580.93475.0
Percentage of Revenues73.065.966.165.552.774.177.478.278.376.778.478.878.577.9-25.879.879.4
Percentage of Revenues alk:PassengerTickets alk:PassengerRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CargoAndFreight, alk:CargoandOtherRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value5744434539465260595052555141424748
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues3.75.55.36.49.32.82.32.52.62.72.52.52.42.2-0.72.22.3
Percentage of Revenues us-gaap:CargoAndFreight alk:CargoandOtherRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger, alk:MileagePlanRevenue


Revenue
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value746456152193186172153160153167139136134143
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax172.1142.2143.6330.4371.2310.0291.5306.0307.7278.2327.5339.0323.8285.1297.9
Percentage of Revenues9.29.113.39.38.77.87.58.27.86.97.77.6-2.36.46.8
Percentage of Revenues us-gaap:Passenger alk:MileagePlanRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger, alk:PassengerRevenue


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1352659657572309148120572211211117161907204319971684179619581945
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax2371.91497.71527.91271.1792.33219.63955.83685.03578.03432.03667.33714.53915.74107.34276.24166.04052.1
Percentage of Revenues88.582.781.381.673.490.592.392.592.391.592.492.492.691.9-30.292.892.5
Percentage of Revenues us-gaap:Passenger alk:PassengerRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Revenue From Contract With Customer Including Assessed Tax

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax

alk:MileagePlanServicesOther


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value118948473109118118110114108107105109
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues7.711.812.017.36.74.95.25.95.25.05.85.05.2
Percentage of Revenues alk:MileagePlanServicesOther0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CargoAndFreight


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value57444539466059505551414748
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax48.346.853.653.442.250.850.045.548.247.238.344.844.0
Percentage of Revenues3.75.56.49.32.82.52.62.72.52.42.22.22.3
Percentage of Revenues us-gaap:CargoAndFreight0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1352659572309148122112111171620431997168419581945
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1145.8701.1681.0423.31358.71873.71789.01560.01792.11849.11573.81864.81784.4
Percentage of Revenues88.582.781.673.490.592.592.391.592.492.691.992.892.5
Percentage of Revenues us-gaap:Passenger0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

alk:CapacityPurchaseAgreements, alk:ConsolidatingAndOther


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-111.0-104.0-81.0-105.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-94.1-110.6-111.0-96.3
Percentage of Revenues-7.3-13.0-19.2-6.4
Percentage of Revenues alk:CapacityPurchaseAgreements alk:ConsolidatingAndOther0.00.00.00.0

alk:CapacityPurchaseAgreements, alk:Horizon


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1111049581105112112116128137110112108
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax94.1110.6113.1111.096.394.994.9105.5112.3126.9102.8106.799.1
Percentage of Revenues7.313.013.619.26.44.74.96.25.86.46.05.35.1
Percentage of Revenues alk:CapacityPurchaseAgreements alk:Horizon0.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:CapacityPurchaseAgreements, us-gaap:IntersegmentElimination


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value-95.0-81.0-105.0-112.0-112.0-116.0-128.0-137.0-110.0-112.0-108.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-113.1-111.0-96.3-94.9-94.9-105.5-112.3-126.9-102.8-106.7-99.1
Percentage of Revenues-13.6-19.2-6.4-4.7-4.9-6.2-5.8-6.4-6.0-5.3-5.1
Percentage of Revenues alk:CapacityPurchaseAgreements us-gaap:IntersegmentElimination0.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanServicesOther, alk:AirGroupAdjusted


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value118948473109118118110114108107105109
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues7.711.812.017.36.74.95.25.95.25.05.85.05.2
Percentage of Revenues alk:MileagePlanServicesOther alk:AirGroupAdjusted0.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanServicesOther, alk:AlaskaMainline


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value10280655698107105100104999897101
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax86.485.177.476.789.990.789.090.991.291.791.692.492.7
Percentage of Revenues6.710.09.313.36.04.54.65.34.74.65.34.64.8
Percentage of Revenues alk:MileagePlanServicesOther alk:AlaskaMainline0.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:MileagePlanServicesOther, alk:AlaskaRegional


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1614191711111310.010.09.09.08.08.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax13.614.922.623.310.19.311.09.18.88.38.47.67.3
Percentage of Revenues1.01.82.74.00.70.50.60.50.50.40.50.40.4
Percentage of Revenues alk:MileagePlanServicesOther alk:AlaskaRegional0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CargoAndFreight, alk:AirGroupAdjusted


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value57444539466059505551414748
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax48.346.853.653.442.250.850.045.548.247.238.344.844.0
Percentage of Revenues3.75.56.49.32.82.52.62.72.52.42.22.22.3
Percentage of Revenues us-gaap:CargoAndFreight alk:AirGroupAdjusted0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CargoAndFreight, alk:AlaskaMainline


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value55444539445857485349404645
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax46.646.853.653.440.449.248.343.646.545.437.443.841.3
Percentage of Revenues3.65.56.49.32.72.42.52.62.42.32.22.22.1
Percentage of Revenues us-gaap:CargoAndFreight alk:AlaskaMainline0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CargoAndFreight, alk:ConsolidatingAndOther


Revenue
Period End2021-06-302020-06-302020-03-31
Value2.00.02.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1.70.01.8
Percentage of Revenues0.10.00.1
Percentage of Revenues us-gaap:CargoAndFreight alk:ConsolidatingAndOther0.00.00.0

us-gaap:CargoAndFreight, us-gaap:IntersegmentElimination


Revenue
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value0.00.02.01.02.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax0.00.01.80.81.70.00.00.00.00.00.0
Percentage of Revenues0.00.00.10.00.10.00.00.00.00.00.0
Percentage of Revenues us-gaap:CargoAndFreight us-gaap:IntersegmentElimination0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger, alk:AirGroupAdjusted


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1352659572309148122112111171620431997168419581945
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1145.8701.1681.0423.31358.71873.71789.01560.01792.11849.11573.81864.81784.4
Percentage of Revenues88.582.781.673.490.592.592.391.592.492.691.992.892.5
Percentage of Revenues us-gaap:Passenger alk:AirGroupAdjusted0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger, alk:AlaskaMainline


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value1072506401225123418501767142217271711144116771677
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax908.5538.3477.4308.21132.11567.81497.51292.71514.91584.31346.71597.11538.5
Percentage of Revenues70.263.557.253.475.477.477.275.878.179.478.779.579.8
Percentage of Revenues us-gaap:Passenger alk:AlaskaMainline0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Passenger, alk:AlaskaRegional


Revenue
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value28015317184247361344294316286243281268
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax237.3162.8203.6115.1226.6305.9291.5267.3277.2264.8227.1267.6245.9
Percentage of Revenues18.319.224.420.015.115.115.015.714.313.313.313.312.7
Percentage of Revenues us-gaap:Passenger alk:AlaskaRegional0.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value1527797808701421163622282389228818762064221221561832-5952.0211021021749-4407.01566149413470.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01039-3273.511981110965
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1294.1847.90.0834.5576.71500.90.02024.61939.01705.50.01940.41996.31712.10.02009.51928.40.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0
Percentage of Revenues alk:AirGroupAdjusted0.00.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0

alk:AlaskaMainline


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value1229630622511320137618672015192915701741188418591579-5147.0182018231517-3661.01293124611220.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0849-2679.5981912785
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1041.5670.20.0608.3438.41262.40.01707.61634.71427.30.01652.61721.31475.70.01733.31672.50.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues80.579.077.072.976.084.183.884.384.383.784.485.286.286.286.586.386.786.783.182.683.483.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.081.881.981.982.281.4
Percentage of Revenues alk:AlaskaMainline0.00.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0

alk:AlaskaRegional


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value296167185190101258359373357305323326296252-802.0289278230-742.02712472240.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0187-587.7214195177
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax250.8177.70.0226.2138.4236.70.0316.1302.5277.30.0286.0274.1235.50.0275.2255.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues19.421.022.927.124.015.816.115.615.616.315.614.713.713.813.513.713.213.216.817.316.516.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.018.118.017.917.618.4
Percentage of Revenues alk:AlaskaRegional0.00.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.00.0100.0100.0100.0

alk:ConsolidatingAndOther


Revenue
Period End2021-06-302021-03-312020-06-302020-03-31
Value-109.0-104.0-81.0-103.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-92.4-110.6-111.0-94.5
Percentage of Revenues-7.1-13.0-19.2-6.3
Percentage of Revenues alk:ConsolidatingAndOther0.00.00.00.0

alk:Horizon


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value11110410595811051101121121171331301381111061131099899110111104105105999994998791948891949796898883939597169180171
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax94.1110.60.0113.1111.096.30.094.994.9106.40.0114.0127.8103.70.0107.6100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Revenues7.313.013.013.619.26.44.94.74.96.26.45.96.46.1-1.85.45.25.6-2.27.07.47.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.08.6-2.57.88.610.017.716.917.5
Percentage of Revenues alk:Horizon0.00.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1527797808701421163622282389228818762064221221561832-5952.0211021021749-4407.01566149413470.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01039-3273.5119811109659581068976829
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Revenues us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value808701421163622282389228818762064221221561832-5952.0211021021749-4407.01566149413470.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01039-3273.511981110965
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0
Percentage of Revenues alk:AirGroupAdjusted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value622511320137618672015192915701741188418591579-5147.0182018231517-3661.01293124611220.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0849-2679.5981912785
Percentage of Revenues77.072.976.084.183.884.384.383.784.485.286.286.286.586.386.786.783.182.683.483.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.081.881.981.982.281.4
Percentage of Revenues77.072.976.084.183.884.384.383.784.485.286.286.286.586.386.786.783.182.683.483.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.081.881.981.982.281.4
Percentage of Revenues alk:AlaskaMainline100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

alk:AlaskaRegional


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value185190101258359373357305323326296252-802.0289278230-742.02712472240.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0187-587.7214195177
Percentage of Revenues22.927.124.015.816.115.615.616.315.614.713.713.813.513.713.213.216.817.316.516.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.018.118.017.917.618.4
Percentage of Revenues22.927.124.015.816.115.615.616.315.614.713.713.813.513.713.213.216.817.316.516.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.018.118.017.917.618.4
Percentage of Revenues alk:AlaskaRegional100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

alk:Horizon


Revenuesus-gaap:
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value10595811051101121121171331301381111061131099899110111104105105999994998791948891949796898883939597169180171
Percentage of Revenues13.013.619.26.44.94.74.96.26.45.96.46.1-1.85.45.25.6-2.27.07.47.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.08.6-2.57.88.610.017.716.917.5
Percentage of Revenues13.013.619.26.44.94.74.96.26.45.96.46.1-1.85.45.25.6-2.27.07.47.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.08.6-2.57.88.610.017.716.917.5
Percentage of Revenues alk:Horizon100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IntersegmentElimination


Revenuesus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-95.0-81.0-103.0-108.0-111.0-110.0-116.0-133.0-128.0-137.0-110.0-109.0-112.0-108.0-97.0-102.0-109.0-110.0-103.0-105.0-105.0-99.0-99.0-94.0-99.0-87.0-91.0-94.0-88.0-91.0-94.0-97.0-96.0-89.0-87.0-89.7-91.2-93.5-94.6-71.5-69.0-67.4
Percentage of Revenues-13.6-19.2-6.3-4.8-4.6-4.8-6.2-6.4-5.8-6.4-6.01.8-5.3-5.1-5.52.3-7.0-7.4-7.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-8.42.7-7.6-8.4-9.8-7.5-6.5-6.9
Percentage of Revenues-13.6-19.2-6.3-4.8-4.6-4.8-6.2-6.4-5.8-6.4-6.01.8-5.3-5.1-5.52.3-7.0-7.4-7.60.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-8.42.7-7.6-8.4-9.8-7.5-6.5-6.9
Percentage of Revenues us-gaap:IntersegmentElimination100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Assets

us-gaap:Assets

us-gaap:Assets


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14656142621404614749139981336312993129831295112640109121089311055108481074010739107201030299628699703568296533656464806410618162366314606158385862585256445505543654235382519552605233511150164996
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:StatementBusinessSegments

alk:AlaskaAirlines


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value199201995119754205862026119677192071912919050186981685314725153341508816663163821627215735152601094991018630812979227567715367726655647361245832573155825346517750824994489448034610
Percentage of Assets135.9139.9140.6139.6144.7147.2147.8147.3147.1147.9154.4135.2138.7139.1155.1152.5151.8152.7153.2125.9129.4126.4124.4120.7116.8111.6109.6106.7102.5101.099.997.895.494.794.093.592.190.992.591.9
Percentage of Assets135.9139.9140.6139.6144.7147.2147.8147.3147.1147.9154.4135.2138.7139.1155.1152.5151.8152.7153.2125.9129.4126.4124.4120.7116.8111.6109.6106.7102.5101.099.997.895.494.794.093.592.190.992.591.9
Percentage of Assets alk:AlaskaAirlines100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Assetsus-gaap:
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value1975419207168531665015260
Percentage of Assets140.6147.8154.4155.0153.2
Percentage of Assets140.6147.8154.4155.0153.2
Percentage of Assets alk:AlaskaMainline100.0100.0100.0100.0100.0

alk:ConsolidatingAndOther


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312019-12-31
Value-6515.0-6889.0-6878.0-7480.0
Percentage of Assets-44.5-48.3-49.0-57.6
Percentage of Assets-44.5-48.3-49.0-57.6
Percentage of Assets alk:ConsolidatingAndOther100.0100.0100.0100.0

alk:Horizon


Assetsus-gaap:
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value1251120011701231119911831266123112221209122910371039945929914834719690716729717718763781821818836857849840850868825823850864851846794816747
Percentage of Assets8.58.48.38.38.68.99.79.59.49.611.39.59.48.78.68.57.87.06.98.210.410.511.011.612.112.813.213.413.614.014.414.514.814.615.015.715.915.816.315.115.614.9
Percentage of Assets8.58.48.38.38.68.99.79.59.49.611.39.59.48.78.68.57.87.06.98.210.410.511.011.612.112.813.213.413.614.014.414.514.814.615.015.715.915.816.315.115.614.9
Percentage of Assets alk:Horizon100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:MaterialReconcilingItems


Assetsus-gaap:
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value-7068.0-7462.0-7497.0-7480.0-7377.0-7321.0-7267.0-7170.0-4869.0-5318.0-5185.0-6839.0-6557.0-6386.0-6152.0-5988.0547952004929473441613877363835523324312429132762240320701832
Percentage of Assets-47.9-53.3-56.1-57.6-56.8-56.5-57.5-65.7-44.7-48.1-47.8-63.7-61.1-59.6-59.7-60.163.073.972.272.563.459.856.857.553.349.548.147.341.035.433.3
Percentage of Assets-47.9-53.3-56.1-57.6-56.8-56.5-57.5-65.7-44.7-48.1-47.8-63.7-61.1-59.6-59.7-60.163.073.972.272.563.459.856.857.553.349.548.147.341.035.433.3
Percentage of Assets us-gaap:MaterialReconcilingItems100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1465614262140461474913998133631299312983129511264010912108931105510848107401073910720103029962869970356829653365646480641061816236631460615838586258525644550554235382519552605233511150164996
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value3324287529883454386140154331425239733746375137913593343937213491326430142931286426272455241123652219216621272229220020952029180215431462142112831218117312641206117011058726611025
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets22.720.221.323.427.630.033.332.830.729.634.434.832.531.734.632.530.429.329.432.937.335.936.936.034.233.834.435.734.834.634.830.726.425.925.823.722.622.624.023.122.922.017.50.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-487.0-494.0-494.0-450.0-458.0-482.0-465.0-421.0-422.0-433.0-448.0-428.0-435.0-440.0-380.0-305.0-303.0-310.0-183.0-436.0-390.0-256.0-260.0-263.7-267.2-240.0-328.3-133.3
Percentage of StockholdersEquity-14.7-17.2-16.5-13.0-11.9-12.0-10.7-9.9-10.6-11.6-11.9-11.3-12.1-12.8-10.2-10.4-12.6-14.6-9.0-30.7-33.2-20.2-21.5-22.5-24.2-27.5-49.6-13.0
Percentage of Assets-3.3-3.5-3.5-3.1-3.3-3.6-3.6-3.2-3.3-3.4-4.1-3.9-3.9-4.1-3.5-3.1-4.6-5.0-3.1-7.9-7.5-4.9-5.0-5.2-5.3-4.80.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value45440939136635031430529727026123222419819016411073296538660840843838828815767915899
Percentage of StockholdersEquity13.714.213.110.69.17.87.07.06.87.06.25.95.55.54.43.83.013.926.546.471.666.769.570.873.887.9138.287.7
Percentage of Assets3.12.92.82.52.52.32.32.32.12.12.12.11.81.81.51.11.14.89.212.016.216.016.016.216.315.40.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.069703737373737354342
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.44.93.23.03.13.23.34.16.54.2
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.21.30.70.70.70.70.70.70.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value40303633376442114642485651334996471744984534455043734219445435682890214416071127810746669640566315193329
Percentage of StockholdersEquity121.2126.4126.0121.9120.2120.9118.5117.5118.7120.1120.9120.0121.7122.7119.7121.7119.9100.879.279.369.159.155.554.751.236.129.232.1
Percentage of Assets27.525.526.828.633.236.339.538.536.435.641.641.839.638.941.535.844.234.727.520.515.614.212.812.511.36.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-674.0-674.0-674.0-674.0-674.0-674.0-643.0-621.0-593.0-581.0-568.0-556.0-544.0-531.0-518.0-443.0-250.0-4.0-2.00.0-125.3-107.4-79.2-72.2-46.0-5.7-161.4-112.5
Percentage of StockholdersEquity-20.3-23.4-22.6-19.5-17.5-16.8-14.8-14.6-14.9-15.5-15.1-14.7-15.1-15.4-13.9-15.1-10.4-0.2-0.10.0-10.7-8.5-6.6-6.2-4.2-0.7-24.4-11.0
Percentage of Assets-4.6-4.7-4.8-4.6-4.8-5.0-4.9-4.8-4.6-4.6-5.2-5.1-4.9-4.9-4.8-4.4-3.8-0.1-0.00.0-2.4-2.0-1.5-1.4-0.9-0.10.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4771428440064465324425722037220222182001178720562216211421462214242522132050360020031923166317151654177617561799202019341762193519861839173716981656159517261675159616621634
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets32.630.028.530.323.219.215.717.017.115.816.418.920.019.520.020.622.621.520.641.428.528.225.526.125.527.728.428.832.031.930.233.033.932.631.631.330.830.732.832.031.233.132.7

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
Value1025107613701855150981122123724421510517410217719414419818332818188178738845511073422908041579512227354810267676089129108117164283204
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 Assets7.07.59.812.610.86.11.71.81.91.71.01.60.91.61.81.31.81.83.320.91.21.11.11.30.70.81.70.50.31.51.40.71.01.72.20.50.70.92.01.31.31.21.80.00.00.03.30.00.0

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-31
Value1042109213861867152082223224925422511418410818319714419832873
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.17.79.912.710.96.21.81.92.01.81.01.71.01.71.81.31.83.31.1

Marketable Securities Current

us-gaap:MarketableSecuritiesCurrent

us-gaap:MarketableSecuritiesCurrent


Marketable
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2926247319761904129413141300138213831221113112231466135114271596172415271252140815261486125511701147126111101309148813301250140413721170113011581150109310381198108698211181027
Percentage of MarketableSecuritiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets20.017.314.112.99.29.810.010.610.79.710.411.213.312.513.314.916.114.812.616.221.721.819.217.817.719.718.021.023.621.921.424.023.420.720.521.321.220.320.022.820.819.222.320.6

Receivables Net Current

us-gaap:ReceivablesNetCurrent

us-gaap:ReceivablesNetCurrent


Receivables
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value567517480321280279323377389358366422411350341301326321302232254235212205194187259178203212152182195188130185169168136148167161120111
Percentage of ReceivablesNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.93.63.42.22.02.12.52.93.02.83.43.93.73.23.22.83.03.13.02.73.63.43.23.13.02.94.22.93.23.52.63.13.33.32.43.43.13.12.62.83.23.22.42.2

us-gaap:ReceivablesNetCurrent us-gaap:ContractWithCustomerSalesChannel

alk:MileagePlanRevenue


Receivables
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value615248454288105103122115119106103101
Percentage of ReceivablesNetCurrent10.810.110.014.015.031.532.527.331.432.132.525.125.129.6
Percentage of Assets0.40.40.30.30.30.70.80.80.90.91.11.00.90.9
Percentage of Assets alk:MileagePlanRevenue0.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Inventory Net

us-gaap:InventoryNet

us-gaap:InventoryNet


Inventory
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value5257575756687263555860575762575752504744454551525852586461586060596158524745444452454545
Percentage of InventoryNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.40.40.40.40.40.50.60.50.40.50.50.50.50.60.50.50.50.50.50.50.60.70.80.80.90.80.91.01.01.01.01.01.01.11.11.00.90.80.90.81.00.90.90.9

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent


Prepaid
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value2011611233281051001211431471491251801801741271161251321219897797274871021051001341249510511413212311612110093106
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.10.92.20.80.70.91.11.11.21.11.71.61.61.21.11.21.31.21.11.41.21.11.11.31.61.71.62.12.01.61.81.92.32.22.12.21.91.82.1

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value9831976097429841102291016110388102271005198621002396629584941492759308906188178595790877437529741672687165688166166494629160685961582657155564547252885230506649964853476346264506
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets67.168.469.466.773.176.080.078.877.678.091.988.786.786.886.486.784.585.686.390.9110.1110.3113.5110.7110.6107.3107.0104.199.6100.1102.199.497.798.699.497.597.297.595.092.793.292.290.2

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
Value37033616353134603434330734863393330732333242316730913011299130783059300829292877278426992614253424602384231722502189213820682034199019251863180517401727166516461603156115091339
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 Assets25.325.425.123.524.524.726.826.125.525.629.729.128.027.827.828.728.529.229.433.139.639.540.038.638.037.237.536.134.735.335.434.734.034.133.833.232.132.132.131.330.630.630.126.8

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value6128614462116381679568546902683467446629678164956493640362846230600258095666503149594830480247344705449742994244410239303893379237253639360935473503340133503249320231173167
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets41.843.144.243.348.551.353.152.652.152.462.159.658.759.058.558.056.056.456.957.870.570.773.572.172.670.269.668.165.064.866.764.763.764.565.665.465.165.563.762.162.662.163.4

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value19431943194319431943194319431943194319431943194319431943194319341940194219340.0
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets13.313.613.813.213.914.515.015.015.015.417.817.817.617.918.118.018.118.919.40.0

Intangible Assets Net Excluding Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value1031051071071091101221231251271271281301321331351371391430.0
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets0.70.70.80.70.80.80.90.91.01.01.21.21.21.21.21.31.31.31.40.0

Operating Lease Right Of Use Asset

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OperatingLeaseRightOfUseAsset


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value13751423140015161568158417111647169617150.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets9.410.010.010.311.211.913.212.713.113.60.0

us-gaap:OperatingLeaseRightOfUseAsset us-gaap:PropertySubjectToOrAvailableForOperatingLease

alk:Aircraft


Operating
Period End2020-12-312019-12-31
Value7501049
Percentage of OperatingLeaseRightOfUseAsset53.661.3
Percentage of Assets5.38.1
Percentage of Assets alk:Aircraft0.00.0

alk:AirportFacilities


Operating
Period End2020-12-312019-12-31
Value1618
Percentage of OperatingLeaseRightOfUseAsset1.11.1
Percentage of Assets0.10.1
Percentage of Assets alk:AirportFacilities0.00.0

alk:CPAAircraft


Operating
Period End2020-12-312019-12-31
Value579596
Percentage of OperatingLeaseRightOfUseAsset41.434.8
Percentage of Assets4.14.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Operating
Period End2020-12-312019-12-31
Value5548
Percentage of OperatingLeaseRightOfUseAsset3.92.8
Percentage of Assets0.40.4
Percentage of Assets alk:Corporaterealestate0.00.0

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
Value33636337933733930027823422522527427127325623422621619916968737668115121137126193192197179126128143120129138148127136223211167143
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 Assets2.32.52.72.32.42.22.11.81.71.82.52.52.52.42.22.12.01.91.70.81.01.11.01.81.92.12.03.13.03.33.12.12.22.52.22.42.62.82.52.64.34.13.32.9

Other Assets

us-gaap:OtherAssets

us-gaap:OtherAssets


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-31
Value375738343829390339593937405439473989401023442342234623312310229522932280224665
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets25.626.927.326.528.329.531.230.430.831.721.521.521.221.521.521.421.422.122.51.0

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
Value1591331089310211914612015615713211411510212097959592717863636156576268717564607110165701101291038871596063
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 Assets1.10.90.80.60.70.91.10.91.21.21.21.01.00.91.10.90.90.90.90.81.10.91.00.90.90.91.01.11.11.21.11.01.21.81.21.32.02.42.01.71.41.21.21.3

Accrued Liabilities Current

us-gaap:AccruedLiabilitiesCurrent

us-gaap:AccruedLiabilitiesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value661541424406327382431476505480416452483433918886979909878735757809661698736731629680706672612676711568539537558551513491544533501474
Percentage of AccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.53.83.02.82.32.93.33.73.93.83.84.14.44.08.58.39.18.88.88.410.811.810.110.611.411.410.210.911.211.110.511.512.110.19.89.910.310.29.99.310.410.410.09.5

Contract With Customer Liability Current

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:ContractWithCustomerLiabilityCurrent


Contract
Period End2020-09-302020-06-302020-03-312019-12-312018-12-31
Value107111311110900788
Percentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0
Percentage of Assets7.38.18.36.97.2

us-gaap:ContractWithCustomerLiabilityCurrent us-gaap:ProductOrService

alk:AirTrafficLiability


Contract
Period End2020-12-312019-12-31
Value1073900
Percentage of ContractWithCustomerLiabilityCurrent0.0100.0
Percentage of Assets7.66.9
Percentage of Assets alk:AirTrafficLiability0.00.0

alk:MileagePlanRevenue


Contract
Period End2021-06-302021-03-312020-12-312019-12-31
Value922818733750
Percentage of ContractWithCustomerLiabilityCurrent0.00.00.083.3
Percentage of Assets6.35.75.25.8
Percentage of Assets alk:MileagePlanRevenue0.00.00.00.0

alk:PassengerRevenue


Contract
Period End2021-06-302021-03-312020-12-31
Value153312971073
Percentage of ContractWithCustomerLiabilityCurrent0.00.00.0
Percentage of Assets10.59.17.6
Percentage of Assets alk:PassengerRevenue0.00.00.0

Debt Current

us-gaap:DebtCurrent

us-gaap:DebtCurrent


Debt
Period End2021-06-302021-03-312020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value86912461138235265288300486345314387307334337332319275117116115117116118117115114113117111110106161167183210207213253169221156
Percentage of DebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.98.78.11.82.02.22.44.53.22.83.62.93.13.13.23.23.21.71.71.81.81.81.81.91.81.81.92.01.91.91.92.93.13.43.94.04.14.93.34.43.1

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4846476242934207412037303201334635343386294228883036299227002765297428352535212320612069180618541927188016711767186417551580165017561598150116641673150915181628148414241269
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets33.133.430.628.529.427.924.625.827.326.827.026.527.527.625.125.727.727.525.424.429.330.327.628.229.729.327.028.329.529.027.128.130.028.327.330.731.129.128.931.129.028.425.4

Long Term Debt Current

us-gaap:LongTermDebtCurrent

us-gaap:LongTermDebtCurrent


Long
Period End2021-06-302021-03-312020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value86912461138235265288300486345314387307334337332319275117116115117116118117115114113117111110106161167183210207213253221
Percentage of LongTermDebtCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.98.78.11.82.02.22.44.53.22.83.62.93.13.13.23.23.21.71.71.81.81.81.81.91.81.81.92.01.91.91.92.93.13.43.94.04.14.94.4

Operating Lease Liability Current

us-gaap:OperatingLeaseLiabilityCurrent

us-gaap:OperatingLeaseLiabilityCurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value2632712902832732662692682732750.0
Percentage of OperatingLeaseLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets1.81.92.11.92.02.02.12.12.12.20.0

Liabilities Noncurrent

us-gaap:LiabilitiesNoncurrent

us-gaap:LiabilitiesNoncurrent


Liabilities
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4416446844154197394139063844260225302428235523382116201319221851185118381774174517521705171416971530150514901475162817391744171215191453141312981244118111731155
Percentage of LiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets29.931.933.032.330.430.230.423.823.222.021.721.819.718.818.718.621.326.126.026.726.726.326.727.524.523.824.625.327.829.730.931.128.027.027.224.723.823.123.423.1

Long Term Debt

us-gaap:LongTermDebt

us-gaap:LongTermDebt


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value3188357134953822263622621499170918261964210320292312244925692701280628632964213662664768671074576880382585983487189392494610321066114012471306139214081534
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets21.825.024.925.918.816.911.513.214.115.519.318.620.922.623.925.226.227.829.824.68.99.510.510.811.512.013.013.213.613.814.915.215.816.818.719.621.023.225.226.526.930.6

us-gaap:LongTermDebt us-gaap:DebtInstrument

alk:FixedRateNotesPayableDueThrough2024


Long
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value19847564295911794744915205405675876146336606787037217467648448649339711002106311481233
Percentage of LongTermDebt5.731.730.537.339.875.775.975.876.176.176.476.576.776.881.380.780.780.780.881.881.181.877.976.776.381.580.4
Percentage of Assets1.43.75.98.911.86.77.28.08.28.89.29.910.210.511.212.012.312.713.515.315.917.218.019.320.221.924.6
Percentage of Assets alk:FixedRateNotesPayableDueThrough20240.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

alk:Fixedratenotespayableduethrough2029


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value180186198427446457475569642
Percentage of LongTermDebt5.65.25.711.216.920.231.733.330.5
Percentage of Assets1.21.31.42.93.23.43.74.45.9
Percentage of Assets alk:Fixedratenotespayableduethrough20290.00.00.00.00.00.00.00.00.0

alk:July2020EETC


Long
Period End2021-06-302021-03-312020-12-312020-09-30
Value1116111611741174
Percentage of LongTermDebt35.031.333.630.7
Percentage of Assets7.67.88.48.0
Percentage of Assets alk:July2020EETC0.00.00.00.0

alk:PSPNotesPayableThrough2031


Long
Period End2021-06-302021-03-312020-12-31
Value600426290
Percentage of LongTermDebt18.811.98.3
Percentage of Assets4.13.02.1
Percentage of Assets alk:PSPNotesPayableThrough20310.00.00.0

alk:VariableRateNotesPayableDueThrough2029


Long
Period End2020-12-31
Value1866
Percentage of LongTermDebt53.4
Percentage of Assets13.3
Percentage of Assets alk:VariableRateNotesPayableDueThrough20290.0

alk:Variableratenotespayableduethrough2029Member


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value131518761866196619251816103211501473
Percentage of LongTermDebt41.252.553.451.473.080.368.867.370.0
Percentage of Assets9.013.213.313.313.813.67.98.913.5
Percentage of Assets alk:Variableratenotespayableduethrough2029Member0.00.00.00.00.00.00.00.00.0

us-gaap:LongTermDebt us-gaap:LongtermDebtType

alk:VariableRatedebtwithinterestrateswap


Long
Period End2020-09-302020-06-302020-03-312019-09-30
Value642666694745
Percentage of LongTermDebt16.825.330.743.6
Percentage of Assets4.44.85.25.7
Percentage of Assets alk:VariableRatedebtwithinterestrateswap0.00.00.00.0

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent

us-gaap:LongTermDebtNoncurrent


Long
Period End2021-06-302021-03-312020-12-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value231923252357126414441538166416171684199820622262236724692531264518615095315715936296506867107457217547828148408718989571036109911781154127513131699
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.816.316.89.711.111.913.214.815.518.119.021.122.023.024.626.621.47.27.88.79.09.710.111.111.411.811.912.913.313.914.915.816.517.619.321.222.422.124.926.234.0

Long Term Debt And Capital Lease Obligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations


Long
Period End2020-09-302020-06-302020-03-312019-12-31
Value2672154912031264
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0
Percentage of Assets18.111.19.09.7

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312019-12-31
Value439365407715
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0
Percentage of Assets3.02.62.95.5

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
Value660663665601581577571467522513503470464458453323336334331272271270270249247247246124123122123461470479489447452458463336361364367421
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 Assets4.54.64.74.14.24.34.43.64.04.14.64.34.24.24.23.03.13.23.33.13.94.04.13.83.83.94.02.01.92.02.17.98.08.58.98.28.48.58.96.46.97.17.38.4

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent us-gaap:RetirementPlanType

us-gaap:PensionPlansDefinedBenefit


Pension
Period End2020-12-312019-12-312018-12-312017-12-31
Value502412392335
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent75.572.277.974.0
Percentage of Assets3.63.23.63.1
Percentage of Assets us-gaap:PensionPlansDefinedBenefit0.00.00.00.0

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
Value422482524476373253232213197210418428417423451429427438417355366359362341339332327312315309308318318332334213204184176170148108123148
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 Assets2.93.43.73.22.71.91.81.61.51.73.83.93.83.94.24.04.04.34.24.15.25.35.55.25.25.25.35.05.05.15.35.45.45.96.13.93.83.43.43.22.82.12.53.0

Operating Lease Liability Noncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value12221283126813201376137514391376142414430.0
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets8.39.09.08.99.810.311.110.611.011.40.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value195216
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0100.0
Percentage of Assets1.41.7
Percentage of Assets alk:Aircraft0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value8479
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo43.136.6
Percentage of Assets0.60.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value7.06.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo3.62.8
Percentage of Assets0.00.0
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value135190
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0100.0
Percentage of Assets1.01.5
Percentage of Assets alk:Aircraft0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value8479
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree62.241.6
Percentage of Assets0.60.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value7.05.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree5.22.6
Percentage of Assets0.00.0
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value83133
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0100.0
Percentage of Assets0.61.0
Percentage of Assets alk:Aircraft0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value8479
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour101.259.4
Percentage of Assets0.60.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value6.05.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour7.23.8
Percentage of Assets0.00.0
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value7681
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0100.0
Percentage of Assets0.50.6
Percentage of Assets alk:Aircraft0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value8479
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive110.597.5
Percentage of Assets0.60.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value4.05.0
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive5.36.2
Percentage of Assets0.00.0
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value257331
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0100.0
Percentage of Assets1.82.5
Percentage of Assets alk:Aircraft0.00.0

alk:AirportFacilities


Lessee
Period End2020-12-312019-12-31
Value9.011
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive3.53.3
Percentage of Assets0.10.1
Percentage of Assets alk:AirportFacilities0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value261329
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive101.699.4
Percentage of Assets1.92.5
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value7874
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive30.422.4
Percentage of Assets0.60.6
Percentage of Assets alk:Corporaterealestate0.00.0

Operating Lease Liability

us-gaap:OperatingLeaseLiability us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:OperatingLeaseLiability

alk:Aircraft


Operating
Period End2020-12-312019-12-31
Value8761045
Percentage of OperatingLeaseLiability100.0100.0
Percentage of Assets6.28.0
Percentage of Assets alk:Aircraft0.00.0

alk:AirportFacilities


Operating
Period End2020-12-312019-12-31
Value1618
Percentage of OperatingLeaseLiability1.81.7
Percentage of Assets0.10.1
Percentage of Assets alk:AirportFacilities0.00.0

alk:CPAAircraft


Operating
Period End2020-12-312019-12-31
Value610596
Percentage of OperatingLeaseLiability69.657.0
Percentage of Assets4.34.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Operating
Period End2020-12-312019-12-31
Value5649
Percentage of OperatingLeaseLiability6.44.7
Percentage of Assets0.40.4
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value9901196
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0100.0
Percentage of Assets7.09.2
Percentage of Assets alk:Aircraft0.00.0

alk:AirportFacilities


Lessee
Period End2020-12-312019-12-31
Value1922
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue1.91.8
Percentage of Assets0.10.2
Percentage of Assets alk:AirportFacilities0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value681724
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue68.860.5
Percentage of Assets4.85.6
Percentage of Assets alk:CPAAircraft0.00.0

alk:Corporaterealestate


Lessee
Period End2020-12-312019-12-31
Value110103
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue11.18.6
Percentage of Assets0.80.8
Percentage of Assets alk:Corporaterealestate0.00.0

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

alk:Aircraft


Lessee
Period End2020-12-312019-12-31
Value114151
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0100.0
Percentage of Assets0.81.2
Percentage of Assets alk:Aircraft0.00.0

alk:AirportFacilities


Lessee
Period End2020-12-312019-12-31
Value3.04.0
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount2.62.6
Percentage of Assets0.00.0
Percentage of Assets alk:AirportFacilities0.00.0

alk:CPAAircraft


Lessee
Period End2020-12-312019-12-31
Value71128
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount62.384.8
Percentage of Assets0.51.0
Percentage of Assets alk:CPAAircraft0.00.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value3324287529883454386140154331425239733746375137913593343937213491326430142931286426272455241123652219216621272229220020952029180215431462142112831218117312641206117011058726611025
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets22.720.221.323.427.630.033.332.830.729.634.434.832.531.734.632.530.429.329.432.937.335.936.936.034.233.834.435.734.834.634.830.726.425.925.823.722.622.624.023.122.922.017.50.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-487.0-494.0-494.0-450.0-458.0-482.0-465.0-421.0-422.0-433.0-448.0-428.0-435.0-440.0-380.0-305.0-303.0-310.0-183.0-436.0-390.0-256.0-260.0-263.7-267.2-240.0-328.3-133.3
Percentage of StockholdersEquity-14.7-17.2-16.5-13.0-11.9-12.0-10.7-9.9-10.6-11.6-11.9-11.3-12.1-12.8-10.2-10.4-12.6-14.6-9.0-30.7-33.2-20.2-21.5-22.5-24.2-27.5-49.6-13.0
Percentage of Assets-3.3-3.5-3.5-3.1-3.3-3.6-3.6-3.2-3.3-3.4-4.1-3.9-3.9-4.1-3.5-3.1-4.6-5.0-3.1-7.9-7.5-4.9-5.0-5.2-5.3-4.80.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value45440939136635031430529727026123222419819016411073296538660840843838828815767915899
Percentage of StockholdersEquity13.714.213.110.69.17.87.07.06.87.06.25.95.55.54.43.83.013.926.546.471.666.769.570.873.887.9138.287.7
Percentage of Assets3.12.92.82.52.52.32.32.32.12.12.12.11.81.81.51.11.14.89.212.016.216.016.016.216.315.40.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.069703737373737354342
Percentage of StockholdersEquity0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.44.93.23.03.13.23.34.16.54.2
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.21.30.70.70.70.70.70.70.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value40303633376442114642485651334996471744984534455043734219445435682890214416071127810746669640566315193329
Percentage of StockholdersEquity121.2126.4126.0121.9120.2120.9118.5117.5118.7120.1120.9120.0121.7122.7119.7121.7119.9100.879.279.369.159.155.554.751.236.129.232.1
Percentage of Assets27.525.526.828.633.236.339.538.536.435.641.641.839.638.941.535.844.234.727.520.515.614.212.812.511.36.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value-674.0-674.0-674.0-674.0-674.0-674.0-643.0-621.0-593.0-581.0-568.0-556.0-544.0-531.0-518.0-443.0-250.0-4.0-2.00.0-125.3-107.4-79.2-72.2-46.0-5.7-161.4-112.5
Percentage of StockholdersEquity-20.3-23.4-22.6-19.5-17.5-16.8-14.8-14.6-14.9-15.5-15.1-14.7-15.1-15.4-13.9-15.1-10.4-0.2-0.10.0-10.7-8.5-6.6-6.2-4.2-0.7-24.4-11.0
Percentage of Assets-4.6-4.7-4.8-4.6-4.8-5.0-4.9-4.8-4.6-4.6-5.2-5.1-4.9-4.9-4.8-4.4-3.8-0.1-0.00.0-2.4-2.0-1.5-1.4-0.9-0.10.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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
Value1.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.01.0696970707070707071373737373735
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 Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.01.11.21.21.21.21.31.31.31.30.70.70.70.70.70.7

Additional Paid In Capital Common Stock

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AdditionalPaidInCapitalCommonStock


Additional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value4544093913663503143052972702612322241981901641561351261101039186737056211296399551524538625629657660660674677840843838828815767
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.12.92.82.52.52.32.32.32.12.12.12.11.81.81.51.51.31.21.11.21.31.31.11.10.93.34.86.48.78.69.210.710.711.612.012.112.412.616.216.016.016.216.315.4

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


Retained
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value403036333764421146424856513349964717449845344550437342194454411738883629356834883266303928902724247422662144201218311684160715421268116411271082918851810746669640566315
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets27.525.526.828.633.236.339.538.536.435.641.641.839.638.941.538.336.335.235.840.146.444.544.241.538.235.434.732.329.027.827.526.321.720.620.519.916.915.815.614.212.812.511.36.3

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value-487.0-494.0-494.0-450.0-458.0-482.0-465.0-421.0-422.0-433.0-448.0-428.0-435.0-440.0-380.0-289.0-294.0-299.0-305.0-284.0-287.0-294.0-303.0-303.0-304.0-305.0-310.0-178.0-178.0-181.0-183.0-414.0-424.0-429.0-436.0-373.6-380.8-382.4-390.0-256.0-260.0-263.7-267.2-240.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-3.3-3.5-3.5-3.1-3.3-3.6-3.6-3.2-3.3-3.4-4.1-3.9-3.9-4.1-3.5-2.7-2.7-2.9-3.1-3.3-4.1-4.3-4.6-4.6-4.7-4.8-5.0-2.9-2.8-3.0-3.1-7.1-7.2-7.6-7.9-6.9-7.0-7.1-7.5-4.9-5.0-5.2-5.3-4.8

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

alk:AccumulatedOtherComprehensiveIncomeLossBalanceSheetLocation, us-gaap:InterestRateSwap, us-gaap:DesignatedAsHedgingInstrument


Accumulated
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-31
Value-21.0-13.0-1.0-2.05.018-22.0-19.0-21.019-17.0-19.0-18.017-19.0-20.0-29.033343228
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax4.32.80.20.5-1.6-5.97.36.26.9-6.19.610.79.9-9.34.64.76.8-7.6-9.1-8.4-7.4
Percentage of Assets-0.1-0.1-0.0-0.00.10.3-0.3-0.3-0.30.3-0.3-0.3-0.30.3-0.3-0.3-0.50.60.60.60.6
Percentage of Assets alk:AccumulatedOtherComprehensiveIncomeLossBalanceSheetLocation us-gaap:InterestRateSwap us-gaap:DesignatedAsHedgingInstrument0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value6746746746746746746436215935815685565445315184944664434434444443772501278.07.04.05.05.01.02.0210.00.00.00.01251077972465.7
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.64.74.84.64.85.04.94.84.64.65.25.14.94.94.84.64.34.34.45.16.35.53.81.90.10.10.10.10.10.00.00.40.00.00.00.02.42.01.51.40.90.1

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

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value13127.02.09.07.09.0128.09.01221-2.2-2.7-4.6-3.1-1.9-3.7-5.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value13127.02.09.07.09.0128.09.01221-2.2-2.7-4.6
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value840167-350.0-205.028833341348565468209260420306233273614470180307374525355340375514138257393242159230380212115181272183872402491184717227954
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 Revenues55.021.0-43.3-29.268.42.015.314.624.724.910.111.819.516.7-3.912.929.226.9-4.119.625.039.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.017.6-2.720.022.512.34.916.228.66.6

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-527.0-543.0174-643.03.0-127.0-83.0-178.0-344.0-186.0-298.0135-304.0-164.010.0-171.0-483.0-488.0-1981.0-51.0-254.0-336.0-203.0-133.0-173.0-421.077-36.0-418.0-164.0-18.0-168.0-361.0-151.0-131.5-102.8-237.3-173.435-196.7-208.1-33.83.8-59.1-192.0-47.9
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-34.5-68.121.5-91.70.7-7.8-3.7-7.5-15.0-9.9-14.46.1-14.1-9.0-0.2-8.1-23.0-27.945.0-3.3-17.0-24.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-16.7-1.1-16.4-18.7-3.50.4-5.5-19.7-5.8

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-363.082-305.01195407684-275.0-175.0-192.0-171.019-319.0-191.0-156.0-193.0-156.0-116.0-127.03111481-117.0-184.0-167.0-164.0-208.0-149.0-142.0-209.0-43.0-68.0-102.0-78.0-57.0-88.0110-86.7-47.9-63.9-87.8-42.9-35.0-114.3-90.8-92.6-96.7-53.1
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-23.810.3-37.7170.596.741.8-12.3-7.3-8.4-9.10.9-14.4-8.9-8.53.2-7.4-5.5-7.3-7.194.6-7.8-13.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-6.12.7-3.6-3.2-11.8-9.5-8.7-9.9-6.4

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

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value-50.0-294.0347698590-5.029111
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues-3.3-36.949.5165.836.1-0.21.35.9

Depreciation Depletion And Amortization

us-gaap:DepreciationDepletionAndAmortization

us-gaap:DepreciationDepletionAndAmortization


Depreciation
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value989710010510710810610610510610899979497959090821019288848179767675737067676869686565636262616058575856
Percentage of DepreciationDepletionAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value840167-350.0-205.028833341348565468209260420306233273614470180307374525355340375514138257393242159230380212115181272183872402491184717227954
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 Revenues55.021.0-43.3-29.268.42.015.314.624.724.910.111.819.516.7-3.912.929.226.9-4.119.625.039.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.017.6-2.720.022.512.34.916.228.66.6

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value397-131.0-447.0-431.0-214.0-232.01813222624.0232171934.0373266296991142562601841912742341491481981659478289104374416367406477287464122585.3
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues26.0-16.4-55.3-61.5-50.8-14.28.113.511.50.21.19.89.00.2-6.312.614.15.7-2.616.317.413.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.03.9-2.06.52.67.76.811.56.00.6

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


Net
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value397-131.0-431.0-214.0-232.03222624.02171934.064772874
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Revenues26.0-16.4-61.5-50.8-14.213.511.50.29.89.00.2-2.06.52.67.7
Percentage of Revenues us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Share Based Compensation

us-gaap:ShareBasedCompensation

us-gaap:ShareBasedCompensation


Share
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value121210.07.0-2.09.09.04.05.01113179.08.0121812137.06.04.09.03.08.05.09.0-21.06.0174.06.09.03.0142.22.30.25.37.02.20.66.7
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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-527.0-543.0174-643.03.0-127.0-83.0-178.0-344.0-186.0-298.0135-304.0-164.010.0-171.0-483.0-488.0-1981.0-51.0-254.0-336.0-203.0-133.0-173.0-421.077-36.0-418.0-164.0-18.0-168.0-361.0-151.0-131.5-102.8-237.3-173.435-196.7-208.1-33.83.8-59.1-192.0-47.9
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-34.5-68.121.5-91.70.7-7.8-3.7-7.5-15.0-9.9-14.46.1-14.1-9.0-0.2-8.1-23.0-27.945.0-3.3-17.0-24.90.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-16.7-1.1-16.4-18.7-3.50.4-5.5-19.7-5.8

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value75272.0364911916919421811540613118823518532929621616916922111916310928027913520925793171137155103178841569892539214929428525
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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-363.082-305.01195407684-275.0-175.0-192.0-171.019-319.0-191.0-156.0-193.0-156.0-116.0-127.03111481-117.0-184.0-167.0-164.0-208.0-149.0-142.0-209.0-43.0-68.0-102.0-78.0-57.0-88.0110-86.7-47.9-63.9-87.8-42.9-35.0-114.3-90.8-92.6-96.7-53.1
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-23.810.3-37.7170.596.741.8-12.3-7.3-8.4-9.10.9-14.4-8.9-8.53.2-7.4-5.5-7.3-7.194.6-7.8-13.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0-6.12.7-3.6-3.2-11.8-9.5-8.7-9.9-6.4

Proceeds From Issuance Of Long Term Debt

us-gaap:ProceedsFromIssuanceOfLongTermDebt us-gaap:DebtInstrument

us-gaap:ProceedsFromIssuanceOfLongTermDebt

alk:PSPNotesPayableThrough2031


Proceeds
Period End2021-03-31
Value136
Percentage of ProceedsFromIssuanceOfLongTermDebt100.0

alk:Variableratenotespayableduethrough2029Member


Proceeds
Period End2021-06-302021-03-31
Value0.054
Percentage of ProceedsFromIssuanceOfLongTermDebt0.039.7

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
Value566115327113656030622013939326328613812013210658101156362136233523352233273722302188357410659851223689891009139
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

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value0.00.00.04544434343403940393737373734343434242626261717171714140.00.00.0
Percentage of PaymentsOfDividends0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.00.00.03122281213131213122528220.00.00.0661271241191601021061595330763232198.325178.817287.026134.91510
Percentage of PaymentsForRepurchaseOfCommonStock0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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 End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value60.5460.9857.7852.3440.0231.5821.5728.5120.99
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value4077155124544636821064940861812685
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value3540404333223.02.01.00.61.51.323
Percentage of UnrecognizedTaxBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:AircraftPermanentlyParked us-gaap:AircraftType

alk:AircraftPermanentlyParked

alk:Airbus


Aircraft
Period End2020-09-302020-06-302020-03-31
Value8.012.012.0
Percentage of AircraftPermanentlyParked100.0100.0100.0

alk:CARESActPSPWarrantsIssuedValue

alk:CARESActPSPWarrantsIssuedValue


C
Period End2021-06-30
Value1.0
Percentage of CARESActPSPWarrantsIssuedValue100.0

alk:CARESActPSPWarrantsIssuedValue alk:CARESActPSPProgram

alk:CARESPSP1


C
Period End2021-06-30
Value0.0
Percentage of CARESActPSPWarrantsIssuedValue0.0

alk:CARESPSP2


C
Period End2021-06-302021-03-31
Value0.08.0
Percentage of CARESActPSPWarrantsIssuedValue0.00.0

alk:CARESPSP3


C
Period End2021-06-30
Value1.0
Percentage of CARESActPSPWarrantsIssuedValue100.0

alk:CARESActPayrollTaxRelief

alk:CARESActPayrollTaxRelief


C
Period End2021-06-302021-03-312020-12-31
Value138.012
Percentage of CARESActPayrollTaxRelief100.0100.0100.0

alk:COVID19RelatedCreditsIssued

alk:COVID19RelatedCreditsIssued


C
Period End2020-12-31
Value150
Percentage of COVID19RelatedCreditsIssued100.0

alk:ContractwithCustomerLiabilityIncreaseFromIssuanceofCredits us-gaap:ContractWithCustomerSalesChannel

alk:ContractwithCustomerLiabilityIncreaseFromIssuanceofCredits

alk:MileagePlanRevenue


Contractwith
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value188136170173106207239241229222227229218184219204
Percentage of ContractwithCustomerLiabilityIncreaseFromIssuanceofCredits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:OperatingExpensesExcludingFuel

alk:OperatingExpensesExcludingFuel


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value7047551248114765015731506148114221431147914021410139414041313126512441045941875890909837804796758755752723728724710688686666665648644634654636
Percentage of OperatingExpensesExcludingFuel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:OperatingExpensesExcludingFuel us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value12341137109411019421410150114761414140514391380137113631374128912411204964919861890877837804796788755752723728724710688686666665648644632628626
Percentage of OperatingExpensesExcludingFuel175.3150.687.796.0144.989.699.799.799.498.297.398.497.297.897.998.298.196.892.297.798.4100.096.5100.0100.0100.0104.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.795.998.4

alk:AlaskaMainline


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value984893853872746115912331226116711521185112611351131115610771026998776727679701702667645639634605602576589588569547547531532519515504498497
Percentage of OperatingExpensesExcludingFuel139.8118.368.376.0114.873.781.982.882.180.580.180.380.581.182.382.081.180.274.377.377.678.877.279.780.280.383.680.180.179.780.981.280.179.579.879.880.080.279.979.476.178.1

alk:AlaskaRegional


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value286265266248210269280275268274269267249239226219206200189202192186181181169164159162151151145144149147145144139136135136138132
Percentage of OperatingExpensesExcludingFuel40.635.121.321.632.317.118.618.618.819.118.219.017.717.116.116.716.316.118.121.521.920.919.921.621.020.621.021.520.120.919.919.921.021.421.221.820.921.121.021.521.120.9

alk:ConsolidatingAndOther


Operating
Period End2021-06-302021-03-312020-06-302020-03-31
Value-127.0-109.0-82.0-110.0
Percentage of OperatingExpensesExcludingFuel-18.0-14.4-12.6-7.0

alk:Horizon


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value918885786892999495971201181231041031051161031029910110510193909192858686888084899086837883828390
Percentage of OperatingExpensesExcludingFuel12.911.76.86.810.55.86.66.36.76.88.18.48.77.57.38.09.28.39.810.511.511.811.111.111.211.412.111.311.411.912.111.011.812.913.212.912.512.112.913.112.814.2

alk:SpecialCharges


Operating
Period End2021-06-302021-03-312020-06-302020-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-530.0-382.0-292.01630.00.00.00.00.00.00.02.02610
Percentage of OperatingExpensesExcludingFuel-75.3-50.6-44.910.40.00.00.00.00.00.00.00.34.11.6

alk:SpecialRevenueandCharges


Operating
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-30
Value46-292.01635.08.02622393124244022140.00.00.00.00.00.00.00.00.00.00.0
Percentage of OperatingExpensesExcludingFuel4.0-44.910.40.30.61.81.62.82.21.81.93.22.31.60.00.00.00.00.00.00.00.00.00.00.0

us-gaap:IntersegmentElimination


Operating
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-97.0-82.0-110.0-111.0-119.0-116.0-118.0-135.0-131.0-136.0-111.0-111.0-112.0-107.0-97.0-103.0-109.0-111.0-102.0-107.0-104.0-100.0-98.0-97.0-97.0-87.0-90.0-94.0-88.0-92.0-95.0-97.0-96.7-88.7-86.6-89.5-90.7-92.2-94.0
Percentage of OperatingExpensesExcludingFuel-8.5-12.6-7.0-7.4-8.0-8.2-8.2-9.1-9.3-9.6-8.0-7.9-8.5-8.5-7.8-9.9-11.6-12.7-11.5-11.8-12.4-12.4-12.3-12.8-12.8-11.6-12.4-12.9-12.2-13.0-13.8-14.1-14.5-13.3-13.4-13.9-14.3-14.1-14.8

alk:OtherNonoperatingIncomeExpenseOther

alk:OtherNonoperatingIncomeExpenseOther


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value9.010.05.06.05.0-3.0-7.0-10.0-7.0-1.0-12.04.05.03.04.05.06.04.09.09.09.09.08.06.07.09.0185.01.05.07.09.06.75.45.91.33.32.92.7
Percentage of OtherNonoperatingIncomeExpenseOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:OtherNonoperatingIncomeExpenseOther us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value9.010.05.06.05.0-3.0-7.0-10.0-7.0-1.0-12.04.05.03.04.05.06.04.09.09.09.09.08.06.07.09.0185.01.05.07.09.06.75.45.91.33.32.92.7
Percentage of OtherNonoperatingIncomeExpenseOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value9.010.04.06.06.0-3.0-7.0-10.0-5.01.0-5.03.05.03.03.04.05.03.07.07.07.07.07.05.07.09.0186.08.06.06.07.16.55.15.30.93.42.32.1
Percentage of OtherNonoperatingIncomeExpenseOther100.0100.080.0100.0120.0100.0100.0100.071.4-100.041.775.0100.0100.075.080.083.375.077.877.877.877.887.583.3100.0100.0100.0120.0800.0120.085.778.997.094.489.869.2103.079.377.8

us-gaap:IntersegmentElimination


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value1.00.0-1.00.00.00.00.00.00.00.00.0-1.01.00.01.01.02.01.02.03.00.00.00.00.00.01.00.0-1.01.01.0-0.1-0.10.20.1-0.20.4-0.2
Percentage of OtherNonoperatingIncomeExpenseOther20.00.0-20.0-0.0-0.0-0.0-0.0-0.0-0.00.00.0-33.325.00.016.725.022.211.122.233.30.00.00.00.00.020.00.0-20.014.311.1-1.5-1.93.47.7-6.113.8-7.4

alk:PSPGrantRecognized

alk:PSPGrantRecognized


P
Period End2021-06-302021-03-312020-09-302020-06-302019-06-30
Value503411-398.0-362.00.0
Percentage of PSPGrantRecognized100.0100.0100.0100.00.0

alk:PSPGrantRecognized us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


P
Period End2020-12-31
Value10.0
Percentage of PSPGrantRecognized0.0

alk:ProceedsFromPayrollSupportProgramGrant

alk:ProceedsFromPayrollSupportProgramGrant


Proceeds
Period End2021-06-302020-12-312020-09-30
Value0.00.030
Percentage of ProceedsFromPayrollSupportProgramGrant0.00.0100.0

alk:ProceedsFromPayrollSupportProgramGrant alk:CARESActPSPProgram

alk:CARESPSP1


Proceeds
Period End2021-06-30
Value0.0
Percentage of ProceedsFromPayrollSupportProgramGrant0.0

alk:CARESPSP2


Proceeds
Period End2021-06-302021-03-31
Value0.0403
Percentage of ProceedsFromPayrollSupportProgramGrant0.00.0

alk:CARESPSP3


Proceeds
Period End2021-06-30
Value0.0
Percentage of ProceedsFromPayrollSupportProgramGrant0.0

alk:RegionalCarrierExpense

alk:RegionalCarrierExpense


Regional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value3730362926374142424140383937373027272325242320201715
Percentage of RegionalCarrierExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:SpecialItemsImpairmentChargesAndOther

alk:SpecialItemsImpairmentChargesAndOther


Special
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value-4.018277121691600.00.0
Percentage of SpecialItemsImpairmentChargesAndOther100.0100.0100.0100.0100.0100.00.00.0

alk:TotalUnsecuredTermLoanThroughPSPOfCARESAct

alk:TotalUnsecuredTermLoanThroughPSPOfCARESAct


Total
Period End2021-06-30
Value1.0
Percentage of TotalUnsecuredTermLoanThroughPSPOfCARESAct100.0

alk:TotalUnsecuredTermLoanThroughPSPOfCARESAct alk:CARESActPSPProgram

alk:CARESPSP1


Total
Period End2021-06-30
Value0.0
Percentage of TotalUnsecuredTermLoanThroughPSPOfCARESAct0.0

alk:CARESPSP2


Total
Period End2021-06-302021-03-31
Value1.0136
Percentage of TotalUnsecuredTermLoanThroughPSPOfCARESAct100.00.0

alk:CARESPSP3


Total
Period End2021-06-30
Value0.0
Percentage of TotalUnsecuredTermLoanThroughPSPOfCARESAct0.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-30
Value8.08.09.07.0
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued us-gaap:DebtInstrument

alk:CARESActPSPTermLoan


Adjustments
Period End2020-12-31
Value0.0
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued0.0

alk:USTreasuryCARESActLoan


Adjustments
Period End2021-03-312020-12-31
Value6.00.0
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued75.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-30
Value8.08.09.07.0
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued100.0100.0100.0100.0

us-gaap:AircraftMaintenanceMaterialsAndRepairs

us-gaap:AircraftMaintenanceMaterialsAndRepairs


Aircraft
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value10281778445115961061151201151071061071208896877364656871675263635857516054676661555450534949535055
Percentage of AircraftMaintenanceMaterialsAndRepairs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AircraftRental

us-gaap:AircraftRental


Aircraft
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value6262707474818482828382827774707069653425262927262626262729283029303029292928282829303233
Percentage of AircraftRental100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs

us-gaap:AllowanceForDoubtfulAccountsReceivableWriteOffs


Allowance
Period End2020-12-312020-09-302020-06-302020-03-31
Value0005000000.0
Percentage of AllowanceForDoubtfulAccountsReceivableWriteOffs0.00.00.0100.0

us-gaap:AssetImpairmentCharges

us-gaap:AssetImpairmentCharges


Asset
Period End2020-12-312020-09-302020-06-302020-03-31
Value2812169145
Percentage of AssetImpairmentCharges100.0100.0100.0100.0

us-gaap:AssetImpairmentCharges us-gaap:AircraftType

alk:Airbus


Asset
Period End2020-12-312020-09-302020-06-302020-03-31
Value281217083
Percentage of AssetImpairmentCharges100.0100.0101.457.2

alk:Q400


Asset
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.00.0-1.062
Percentage of AssetImpairmentCharges0.00.0-1.442.8

us-gaap:AssetImpairmentCharges us-gaap:AircraftType, us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType

alk:Airbus, alk:Aircraft


Asset
Period End2020-09-302020-06-302020-03-31
Value1210.011
Percentage of AssetImpairmentCharges100.00.07.6

alk:Airbus, alk:LeaseReturnCosts


Asset
Period End2020-09-302020-06-302020-03-31
Value0.0708.0
Percentage of AssetImpairmentCharges0.0101.45.5

alk:Airbus, alk:OperatingLeaseAsset


Asset
Period End2020-09-302020-06-302020-03-31
Value0.00.062
Percentage of AssetImpairmentCharges0.00.042.8

alk:Airbus, us-gaap:Inventories


Asset
Period End2020-09-302020-06-302020-03-31
Value0.00.02.0
Percentage of AssetImpairmentCharges0.00.01.4

alk:Q400, alk:Aircraft


Asset
Period End2020-09-302020-06-302020-03-31
Value0.00.058
Percentage of AssetImpairmentCharges0.00.040.0

alk:Q400, us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations


Asset
Period End2020-09-302020-06-302020-03-31
Value0.0-1.04.0
Percentage of AssetImpairmentCharges0.0-1.42.8

us-gaap:AssetImpairmentCharges us-gaap:ImpairedLongLivedAssetsHeldAndUsedByType

alk:Aircraft


Asset
Period End2020-09-302020-06-302020-03-31
Value1210.069
Percentage of AssetImpairmentCharges100.00.047.6

alk:LeaseReturnCosts


Asset
Period End2020-09-302020-06-302020-03-31
Value0.0708.0
Percentage of AssetImpairmentCharges0.0101.45.5

alk:OperatingLeaseAsset


Asset
Period End2020-09-302020-06-302020-03-31
Value0.00.062
Percentage of AssetImpairmentCharges0.00.042.8

us-gaap:DisposalGroupHeldforsaleNotDiscontinuedOperations


Asset
Period End2020-09-302020-06-302020-03-31
Value0.0-1.04.0
Percentage of AssetImpairmentCharges0.0-1.42.8

us-gaap:Inventories


Asset
Period End2020-09-302020-06-302020-03-31
Value0.00.02.0
Percentage of AssetImpairmentCharges0.00.01.4

us-gaap:BusinessCombinationAcquisitionRelatedCosts

us-gaap:BusinessCombinationAcquisitionRelatedCosts


Business
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value1.01.01.03.05.05.08.0262022396.0302424408122140.0320.00.0
Percentage of BusinessCombinationAcquisitionRelatedCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.00.0

us-gaap:ContractWithCustomerLiabilityRevenueRecognized us-gaap:ContractWithCustomerSalesChannel

us-gaap:ContractWithCustomerLiabilityRevenueRecognized

alk:PassengerRevenue


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value36136180.0-5.0489-5.019894744327794348.02389
Percentage of ContractWithCustomerLiabilityRevenueRecognized100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerLiabilityRevenueRecognized us-gaap:ProductOrService, us-gaap:ContractWithCustomerSalesChannel

alk:MileagePlanServicesOther, alk:MileagePlanRevenue


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-13.0-4.0-2.00.01.0-22.0-27.0-33.0-23.0-28.0-24.0-22.0-25.0-19.0-19.0-10.0
Percentage of ContractWithCustomerLiabilityRevenueRecognized-36.1-2.9-11.10.0-20.0-4.5540.0-173.7-25.8-5.9-55.8-81.5-31.6-4.4-237.5-43.5

alk:PassengerServices, alk:MileagePlanRevenue


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-154.0-84.0-74.0-64.0-56.0-152.0-193.0-186.0-172.0-153.0-160.0-153.0-167.0-139.0-136.0-134.0
Percentage of ContractWithCustomerLiabilityRevenueRecognized-427.8-61.8-411.10.01120.0-31.13860.0-978.9-193.3-32.3-372.1-566.7-211.4-32.0-1700.0-582.6

us-gaap:CostOfServicesCatering

us-gaap:CostOfServicesCatering


Cost
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value352320147.0495557534953535550505050
Percentage of CostOfServicesCatering100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredRevenueRefundPayments1

us-gaap:DeferredRevenueRefundPayments1


Deferred
Period End2020-12-31
Value125
Percentage of DeferredRevenueRefundPayments1100.0

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfGainsLosses

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value9.09.0-9.0-9.0-8.0-9.0-10.0-9.0-9.0-9.0-8.0-9.0-8.0-8.0-6.0-7.0-6.0
Percentage of DefinedBenefitPlanAmortizationOfGainsLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAmortizationOfPriorServiceCostCredit

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312020-09-302019-12-312019-09-302018-12-312018-09-302017-12-312017-09-30
Value0-1000000.00-1000000.00-1000000.00-1000000.0
Percentage of DefinedBenefitPlanAmortizationOfPriorServiceCostCredit0.0100.00.0100.00.0100.00.0100.0

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedReturnOnPlanAssets

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value-30.0-31.0272827282424232427272627262726
Percentage of DefinedBenefitPlanExpectedReturnOnPlanAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanInterestCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanInterestCost

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value1414181919192223222220201920191918
Percentage of DefinedBenefitPlanInterestCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost us-gaap:IncomeStatementLocation, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanNetPeriodicBenefitCost

alk:LaborAndRelatedExpense, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value13131113131110.01112121210.010.0
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NonoperatingIncomeExpense, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value-7.0-8.0-1.00.00.07.08.07.01.01.01.0-2.0-2.0
Percentage of DefinedBenefitPlanNetPeriodicBenefitCost-53.8-61.5-9.10.00.063.680.063.68.38.38.3-20.0-20.0

us-gaap:DefinedBenefitPlanServiceCost us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanServiceCost

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value13139.011131310.01110.011121212129.010.010.0
Percentage of DefinedBenefitPlanServiceCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FuelCosts

us-gaap:FuelCosts


Fuel
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value27420315512559384470486502420539513475409396368344339238225201167213245261235306394360358352363372381371336431318285420397194217220255207
Percentage of FuelCosts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FuelCosts us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Fuel
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value32022516312865375475486499424487508497422410373342329242222211169212240267235312390373366353383371369362357362338328335326276
Percentage of FuelCosts116.8110.8105.2102.4110.297.7101.1100.099.4101.090.499.0104.6103.2103.5101.499.497.1101.798.7105.0101.299.598.0102.3100.0102.099.0103.6102.2100.3105.599.796.997.4106.383.9106.2115.179.982.2142.2

alk:AlaskaMainline


Fuel
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value2531741219045313398411422358415438432367358328304292207188180144182205232203271338324318307337327323314312316294285292285238
Percentage of FuelCosts92.385.778.172.076.381.584.784.684.185.277.085.490.989.790.489.188.486.187.083.689.686.285.483.788.986.488.685.890.088.887.292.887.984.884.792.773.392.399.969.671.7122.6

alk:AlaskaRegional


Fuel
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value665242382062777577667270655552453936353431253035353241524948464644464745454443434138
Percentage of FuelCosts24.125.627.130.433.916.116.415.415.315.713.413.613.713.413.112.211.310.614.715.115.415.014.114.313.413.613.413.213.613.413.112.711.812.112.713.610.513.915.210.310.419.6

alk:ConsolidatingAndOther


Fuel
Period End2021-06-302021-03-31
Value1.0-1.0
Percentage of FuelCosts0.4-0.5

alk:SpecialCharges


Fuel
Period End2021-06-302021-03-312020-06-302020-03-312013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-46.0-22.0-6.09.01.0129.5-21.269-19.9-43.18470-82.0
Percentage of FuelCosts-16.8-10.8-10.22.30.33.12.6-6.316.1-6.2-15.120.117.8-42.2

alk:SpecialRevenueandCharges


Fuel
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-30
Value-3.0-6.09.00.03.0-4.05.0-22.0-13.0-5.02.010.03.0-10.0-2.05.0-6.00.04.0-13.0-8.0-20.01.012-21.0
Percentage of FuelCosts-2.4-10.22.30.00.6-1.01.0-4.6-3.2-1.40.62.91.3-5.0-1.22.0-2.30.01.0-3.6-2.2-5.50.33.1-6.2

us-gaap:IncreaseDecreaseInContractWithCustomerLiability

us-gaap:IncreaseDecreaseInContractWithCustomerLiability


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2362242.0-60.021210-132.0-141.057328
Percentage of IncreaseDecreaseInContractWithCustomerLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-6.039801225444-22.0-125.0-60.0-2.0-24.0-55.0-65.0-2.0198-85.0-84.0-48.0-47.0-6.0-49.08.0-73.0-27.0386.0-87.0-13.0-5.0-9.0-25.0-105.02.0-18.07.3-43.8-31.7-25.8-42.9-44.1-14.6-43.2
Percentage of IncreaseDecreaseInDeferredIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredRevenue

us-gaap:IncreaseDecreaseInDeferredRevenue


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value214895109513319223441435426261731141.0231212361515198.019148.0-1.0231-159.014-2.0199.47.8-4.0167.3-1.1-15.7
Percentage of IncreaseDecreaseInDeferredRevenue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsCapitalizedAdjustment

us-gaap:InterestCostsCapitalizedAdjustment


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value3.03.03.04.01.03.04.04.03.04.04.05.04.05.04.05.04.04.04.06.07.08.09.09.08.08.06.05.04.05.06.06.05.05.0
Percentage of InterestCostsCapitalizedAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsIncurred

us-gaap:InterestCostsIncurred


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value3932341713182022
Percentage of InterestCostsIncurred100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestCostsIncurred us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value341713182022
Percentage of InterestCostsIncurred100.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value281812181921
Percentage of InterestCostsIncurred82.4105.992.3100.095.095.5

alk:Horizon


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value6.05.05.07.07.08.0
Percentage of InterestCostsIncurred17.629.438.538.935.036.4

us-gaap:IntersegmentElimination


Interest
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-31
Value0.0-6.0-4.0-7.0-6.0-7.0
Percentage of InterestCostsIncurred0.0-35.3-30.8-38.9-30.0-31.8

us-gaap:InterestPaidCapitalized

us-gaap:InterestPaidCapitalized


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value3.03.04.01.03.04.03.04.05.04.05.05.04.04.0
Percentage of InterestPaidCapitalized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestPaidCapitalized us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value3.03.04.01.03.04.03.04.05.04.05.05.04.04.0
Percentage of InterestPaidCapitalized100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Interest
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value3.03.04.01.03.04.03.04.04.04.04.05.03.04.0
Percentage of InterestPaidCapitalized100.0100.0100.0100.0100.0100.0100.0100.080.0100.080.0100.075.0100.0

us-gaap:InvestmentIncomeInterest

us-gaap:InvestmentIncomeInterest


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value6.07.08.07.07.09.01111119.09.01110.08.09.09.09.07.07.07.07.06.05.05.06.05.06.05.05.05.04.05.04.04.04.54.55.14.93.54.56.37.66.77.67.77.5
Percentage of InvestmentIncomeInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentIncomeInterest us-gaap:StatementBusinessSegments

alk:AirGroupAdjusted


Investment
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6.07.07.07.09.01111119.09.01110.08.09.09.09.07.07.07.07.06.05.05.06.05.06.05.05.05.04.05.04.04.04.54.55.14.93.54.56.37.6
Percentage of InvestmentIncomeInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:AlaskaMainline


Investment
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value6.07.08.01114161717161415131112119.07.07.07.06.06.04.05.05.05.05.05.05.05.04.05.04.04.05.04.74.44.93.54.67.18.7
Percentage of InvestmentIncomeInterest100.0100.0114.3157.1155.6145.5154.5154.5177.8155.6136.4130.0137.5133.3122.2100.0100.0100.0100.085.7100.080.0100.083.3100.083.3100.0100.0100.0100.0100.0100.0100.0111.1104.486.3100.0100.0102.2112.7114.5

us-gaap:IntersegmentElimination


Investment
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-1.0-4.0-5.0-5.0-6.0-6.0-7.0-5.0-4.0-3.0-3.0-3.0-2.00.00.00.00.00.00.01.00.01.00.01.00.00.00.00.00.00.00.0-0.5-0.20.70.0-0.3-0.1-0.8-1.1
Percentage of InvestmentIncomeInterest-14.3-57.1-55.6-45.5-54.5-54.5-77.8-55.6-36.4-30.0-37.5-33.3-22.20.00.00.00.00.00.020.00.016.70.016.70.00.00.00.00.00.00.0-11.1-4.413.70.0-8.6-2.2-12.7-14.5

us-gaap:LaborAndRelatedExpense

us-gaap:LaborAndRelatedExpense


Labor
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value510493474495472612638608567557561549544536532475469448374340332336331312305306304279281272280285258264267255258256253245242249241240
Percentage of LaborAndRelatedExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LandingFeesAndOtherRentals

us-gaap:LandingFeesAndOtherRentals


Landing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value144129941098313114314311313212813511012612212499115888963807980667172746469557175605861606258625957595957
Percentage of LandingFeesAndOtherRentals100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LineOfCreditFacilityMaximumMonthendOutstandingAmount us-gaap:DebtInstrument

us-gaap:LineOfCreditFacilityMaximumMonthendOutstandingAmount

alk:CreditFacilities12


Line
Period End2021-03-31
Value363
Percentage of LineOfCreditFacilityMaximumMonthendOutstandingAmount100.0

alk:USTreasuryCARESActLoan


Line
Period End2021-03-31
Value135
Percentage of LineOfCreditFacilityMaximumMonthendOutstandingAmount37.2

us-gaap:LossContingencyDamagesSoughtValue us-gaap:LitigationCase

us-gaap:LossContingencyDamagesSoughtValue

alk:VirginAmericaFlightAttendants


Loss
Period End2021-06-302021-03-312020-12-31
Value0.0780.0
Percentage of LossContingencyDamagesSoughtValue0.0100.00.0

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value1.012-2.00.019-3.0-1.0-1.010.0126.01.0-3.0-8.0-5.00.01.02.0-10.0-2.04.08.0-4.00.0-3.04.0-1.0-3.02.02.0-1.03.0-8.0-1.0-2.52.4-0.62.0-1.2-1.81.8
Percentage of OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax

us-gaap:OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value1000000.03000000.0006000000.0-1000000.0-1000000.003000000.04000000.02000000.0-1000000.00-3000000.0-3000000.001000000.01000000.0-6000000.002000000.04000000.0-3000000.00-2000000.03000000.00-2000000.01000000.01000000.001000000.0-4000000.0-1000000.0-1100000.01400000.0-300000.01000000.00-1200000.01200000.0
Percentage of OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax100.0100.00.00.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value1000000.06000000.04000000.02000000.0-1000000.0-19000000.04000000.0-4000000.0-5000000.0-3000000.0-6000000.01000000.02000000.05000000.03000000.01000000.00010000000.01000000.00-2000000.01000000.0-1000000.01000000.0-1000000.0-2000000.02000000.0-1000000.0-1000000.02000000.01000000.05000000.02000000.01600000.0-1400000.0-3900000.0-1000000.02100000.0-11400000.0-2100000.0
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value02000000.01000000.01000000.0-1000000.0-5000000.01000000.00-2000000.0-1000000.0-2000000.01000000.002000000.01000000.01000000.0-1000000.01000000.06000000.01000000.00-2000000.03000000.0-2000000.01000000.0-1000000.000001000000.0-1000000.04000000.02000000.0-300000.0-700000.0-2500000.04000000.0-2700000.0-6900000.0-1200000.0
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax0.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value9.08.0-7.0-8.0-7.0-8.0-8.0-8.055-7.0-7.0-7.0139-5.0-5.0-6.058-5.0-5.0-5.01.0-3.0-5.0-3.0217-2.0-3.0-2.0-326.0-11.0-11.0-10.097-9.9-9.8-10.0215-27.5-6.4
Percentage of OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax

us-gaap:OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value7.06.0-12.0-6.0-6.0-5.0-11.0-6.0-6.0-6.020-5.0-6.0-5.088-3.0-4.0-4.021-4.0-3.0-3.0-3.0-2.0-3.0-2.0129-1.0-2.0-1.0-230.0-6.0-8.0-6.061-6.2-6.1-6.0135-17.2-4.0
Percentage of OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value-2.0-4.03.02.06.03.02.05.00.0-2.0-3.0-2.0-1.0-2.0-1.01.0-1.00.00.00.01.00.0-1.00.00.00.00.01.01.00.00.00.0-1.01.02.02.0-2.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.0100.00.0100.00.00.00.00.0100.0100.00.00.00.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax


Other
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-30
Value-1000000.0-1000000.00-1000000.0-1000000.0-1000000.00-1000000.00-2000000.00-1000000.0-1000000.0-2000000.0-2000000.00-2000000.0-1000000.0-2000000.0-1000000.0-1000000.0-2000000.0-1000000.0-2000000.0-1000000.0-2000000.0-1000000.0-2000000.0-2000000.0-1000000.02000000.0-1000000.0-2000000.0-2000000.01000000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesBeforeTax100.0100.00.0100.0100.0100.00.0100.00.0100.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTax

us-gaap:OtherComprehensiveIncomeLossTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value-2.0-2.01.02.02.02.02.02.02.01.02.02.01.02.01.02.02.010.01.02.01.0-79.01.01.01.01385.03.04.0-36.13.73.73.7-80.1102.42.4
Percentage of OtherComprehensiveIncomeLossTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-31
Value1000000.08000000.02000000.0-2000000.0-25000000.0-5000000.0-7000000.0-5000000.002000000.06000000.00-3000000.01000000.01000000.0-2000000.0-5000000.0-5000000.01000000.0-4000000.00-2000000.0-3000000.0-1000000.07000000.03000000.0-4000000.0-8000000.01000000.0
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value0.0111.02.031-1.00.04.013145.0-2.0-4.0-13.0-9.01.01.03.0-16.0-2.07.012-8.00.0-5.07.0-1.0-4.04.03.0-1.04.0-11.0-1.0-0.95.60.63.7-0.9-1.83.9-2.2
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax0.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherCostAndExpenseOperating

us-gaap:OtherCostAndExpenseOperating


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value11710597897814314813713613814914114114114115014013498928194978294837967818176696567635861646154586054494847
Percentage of OtherCostAndExpenseOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherLaborRelatedExpenses

us-gaap:OtherLaborRelatedExpenses


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value34336542167.03846443543273839374027313231323230323226323029253726212126232116181917162923
Percentage of OtherLaborRelatedExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:OtherOperatingActivitiesCashFlowStatement


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-31
Value31-73.0-52.0112-51.0-211.025-25.042-24.0133-20.040-144.0120-70.081-150.03711-45.017-3.0155095295567-119.0-33.015152-106.01028.640-93.86442-0.8-119.4
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForFlightEquipment

us-gaap:PaymentsForFlightEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value273.03.03.01.0577011411953337781361351252752441601201401779111873245245841591906513412014390157691478057457513929
Percentage of PaymentsForFlightEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForProceedsFromOtherInvestingActivities

us-gaap:PaymentsForProceedsFromOtherInvestingActivities


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
Value-10.05.0311.0-2.0-8.0-4.0-12.0-20.0-5.0-11.0-26.0-2.0-8.0-37.0-28.0-10.00.00.0-2.0-2.0-1.0-54.01.02.0-2.0-14.02.09.0-7.00.04.0-8.07.0-10.20.1-0.6-0.3-19.9-0.8-18.61829-0.1-0.90.4
Percentage of PaymentsForProceedsFromOtherInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForRestructuring

us-gaap:PaymentsForRestructuring


Payments
Period End2021-06-302021-03-31
Value3247
Percentage of PaymentsForRestructuring100.0100.0

us-gaap:PaymentsToAcquireMarketableSecurities

us-gaap:PaymentsToAcquireMarketableSecurities


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
Value128112438701088477527364561534351162143291238161398453557185165252358451165308403155166323305224274440280319273297240101354246181225218294284
Percentage of PaymentsToAcquireMarketableSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireOtherProductiveAssets

us-gaap:PaymentsToAcquireOtherProductiveAssets


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value27116.06.08.035534254292920272926252520184.016151818222139324317254.06.06.0116.14.42.3167.36.24.96.6
Percentage of PaymentsToAcquireOtherProductiveAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireOtherPropertyPlantAndEquipment

us-gaap:PaymentsToAcquireOtherPropertyPlantAndEquipment


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value2113-7.027402746384533403325713429273631252813271813131218241112136.07.09.79.64.814180.6104.9-4.5
Percentage of PaymentsToAcquireOtherPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfDebt us-gaap:SubsequentEventType

us-gaap:ProceedsFromIssuanceOfDebt

us-gaap:SubsequentEvent


Proceeds
Period End2020-07-022020-04-222019-02-15
Value120050254
Percentage of ProceedsFromIssuanceOfDebt100.0100.0100.0

us-gaap:ProceedsFromIssuanceOfSecuredDebt

us-gaap:ProceedsFromIssuanceOfSecuredDebt


Proceeds
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312015-09-302014-09-302013-09-30
Value17418913164408251020.02540.00.00.00.00.00.0
Percentage of ProceedsFromIssuanceOfSecuredDebt100.0100.0100.0100.0100.0100.00.0100.00.00.00.00.00.00.0

us-gaap:ProceedsFromLinesOfCredit us-gaap:DebtInstrument

us-gaap:ProceedsFromLinesOfCredit

alk:USTreasuryCARESActLoan


Proceeds
Period End2020-12-31
Value0.0
Percentage of ProceedsFromLinesOfCredit0.0

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value298.039-8.032-5.03.0142.024-4.0180.0151.0151.0113.05.04.0134.0161.014-24.00.03.0164.0-9.0-6.08.0-32.34.7160.2120.01.6-7.15.44.60.3-13.9
Percentage of ProceedsFromPaymentsForOtherFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities

us-gaap:ProceedsFromSaleAndMaturityOfMarketableSecurities


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value829732798482527511446565388275259383173301319528256285324281217140357142417259353341171227377247226239346271242188258238145314284200185261
Percentage of ProceedsFromSaleAndMaturityOfMarketableSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProfessionalAndContractServicesExpense

us-gaap:ProfessionalAndContractServicesExpense


Professional
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-30
Value545143363072757270727970768180767781646360605.0746867666662606054545351505047484646434140
Percentage of ProfessionalAndContractServicesExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RestructuringCharges

us-gaap:RestructuringCharges


Restructuring
Period End2021-06-302021-03-312020-12-312020-09-302012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value-23.011-102.03220.00.00.00.00.02.026100.09.83.40.0
Percentage of RestructuringCharges100.0100.0100.0100.00.00.00.00.00.0100.0100.0100.00.0100.0100.00.0

us-gaap:SellingExpense

us-gaap:SellingExpense


Selling
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value413318244.05577778772817988788891978163585549515354534555534642475138364544414247453937443833
Percentage of SellingExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod us-gaap:StatementEquityComponents

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod

us-gaap:CommonStock


Share
Period End2021-06-30
Value0.009
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod100.0

us-gaap:StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans

us-gaap:CommonStock


Stock
Period End2021-06-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-03-31
Value0.7161.000.3940.0280.3910.320.312
Percentage of StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensation us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensation

us-gaap:CommonStock


Stock
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.0620.2250.0220.0540.1230.0110.0280.1340.030.0580.163
Percentage of StockIssuedDuringPeriodSharesShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan


Stock
Period End2021-06-302020-06-302019-09-302019-03-312018-09-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value2327202018170.01.50.01.3
Percentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan100.0100.0100.0100.0100.0100.00.0100.00.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302020-06-302020-03-312019-09-302019-03-312018-09-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value23270.0202018170.01.50.01.2
Percentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan100.0100.00.0100.0100.0100.0100.00.0100.00.092.3

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation


Stock
Period End2021-06-302021-03-312020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value1.0-2.00.00.00.00.0-3.00.0-1.0-3.0-5.30.88.27.3
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.00.00.00.00.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-06-302021-03-312020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312011-12-312011-09-302011-06-302011-03-31
Value1.0-2.00.00.00.0-3.00.0-1.0-3.0-5.40.77.97.0
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.00.00.00.0100.00.0100.0100.0101.987.596.395.9

us-gaap:StockRepurchasedDuringPeriodValue us-gaap:ShareRepurchaseProgram

us-gaap:StockRepurchasedDuringPeriodValue

alk:A20151BillionRepurchaseProgram


Stock
Period End2021-03-312019-09-302019-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value0.028123130.00.0671271200.00.0
Percentage of StockRepurchasedDuringPeriodValue0.0100.0100.0100.00.00.0100.0100.0100.00.00.0

alk:AdditionalReliefFromPSPOfCARESAct alk:CARESActPSPProgram

alk:AdditionalReliefFromPSPOfCARESAct

alk:CARESPSP2


Additional
Period End2021-04-29
Value80
Percentage of AdditionalReliefFromPSPOfCARESAct100.0

alk:AdditionalReliefFromPSPOfCARESAct alk:CARESActPSPProgram, us-gaap:SubsequentEventType

alk:CARESPSP2, us-gaap:SubsequentEvent


Additional
Period End2021-04-29
Value80
Percentage of AdditionalReliefFromPSPOfCARESAct100.0

alk:AdditionalReliefFromPSPOfCARESAct us-gaap:ReportingUnit

alk:AlaskaAirlinesAndHorizonAir


Additional
Period End2020-09-26
Value29
Percentage of AdditionalReliefFromPSPOfCARESAct0.0

alk:AircraftMaintenanceDeposits

alk:AircraftMaintenanceDeposits


Aircraft
Period End2020-12-312019-12-312018-12-31
Value24214390
Percentage of AircraftMaintenanceDeposits100.0100.0100.0

alk:COVID19CreditsIssuedBalance

alk:COVID19CreditsIssuedBalance


C
Period End2021-06-302021-03-312020-12-312020-09-30
Value387484569617
Percentage of COVID19CreditsIssuedBalance100.0100.0100.0100.0

alk:DeferredTaxAssetsLeaseholdMaintenance

alk:DeferredTaxAssetsLeaseholdMaintenance


Deferred
Period End2020-12-31
Value-73000000.0
Percentage of DeferredTaxAssetsLeaseholdMaintenance100.0

alk:DeferredTaxAssetsLeasingArrangement

alk:DeferredTaxAssetsLeasingArrangement


Deferred
Period End2020-12-312019-12-312018-12-31
Value3814170.0
Percentage of DeferredTaxAssetsLeasingArrangement100.0100.00.0

alk:DeferredTaxAssetsMileagePlan

alk:DeferredTaxAssetsMileagePlan


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value385337315208310208206185265241237
Percentage of DeferredTaxAssetsMileagePlan100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:LAXRedevelopmentProjectTotalExpectedOutlay

alk:LAXRedevelopmentProjectTotalExpectedOutlay


L
Period End2020-12-31
Value230
Percentage of LAXRedevelopmentProjectTotalExpectedOutlay100.0

alk:LeaseReturnProvisionCurrent

alk:LeaseReturnProvisionCurrent


Lease
Period End2020-12-31
Value-54000000.0
Percentage of LeaseReturnProvisionCurrent100.0

alk:LeaseReturnProvisionNonCurrent

alk:LeaseReturnProvisionNonCurrent


Lease
Period End2020-12-31
Value-246000000.0
Percentage of LeaseReturnProvisionNonCurrent100.0

alk:LeasedAircraftReturnCosts

alk:LeasedAircraftReturnCosts


Leased
Period End2021-03-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value185.01.0152.02.12.9
Percentage of LeasedAircraftReturnCosts100.0100.0100.0100.0100.0100.0100.0

alk:NotesPayableFairValueDisclosureBeforePurchasePriceAccountingFairValueAdjustment us-gaap:FairValueByMeasurementBasis

alk:NotesPayableFairValueDisclosureBeforePurchasePriceAccountingFairValueAdjustment

us-gaap:CarryingReportedAmountFairValueDisclosure


Notes
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value18894444554735675805126397038388749561175
Percentage of NotesPayableFairValueDisclosureBeforePurchasePriceAccountingFairValueAdjustment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:NumberOfMainlineAircraftParked

alk:NumberOfMainlineAircraftParked


Number
Period End2020-09-302020-03-31
Value64.0146.0
Percentage of NumberOfMainlineAircraftParked100.0100.0

alk:OperatingLossAvailableToOffsetPriorYearIncome us-gaap:IncomeTaxAuthority

alk:OperatingLossAvailableToOffsetPriorYearIncome

us-gaap:StateAndLocalJurisdiction


Operating
Period End2020-12-31
Value85
Percentage of OperatingLossAvailableToOffsetPriorYearIncome100.0

alk:PSPInstallmentsReceived alk:CARESActPSPProgram

alk:PSPInstallmentsReceived

alk:CARESPSP1


P
Period End2021-06-302021-03-31
Value0.08.0
Percentage of PSPInstallmentsReceived0.0100.0

alk:CARESPSP2


P
Period End2021-03-31
Value539
Percentage of PSPInstallmentsReceived6737.5

alk:PSPInstallmentsReceived us-gaap:ReportingUnit, us-gaap:SubsequentEventType

alk:AlaskaAirlinesAndHorizonAir, us-gaap:SubsequentEvent


P
Period End2021-01-15
Value266
Percentage of PSPInstallmentsReceived0.0

alk:McGeeAirServices, us-gaap:SubsequentEvent


P
Period End2021-02-052020-08-31
Value6.015
Percentage of PSPInstallmentsReceived0.00.0

alk:PrefundedTrustAccount us-gaap:RetirementPlanType

alk:PrefundedTrustAccount

us-gaap:DefinedBenefitPostretirementHealthCoverage


Prefunded
Period End2020-12-312019-12-312018-12-312017-12-31
Value7000000.06000000.03000000.03000000.0
Percentage of PrefundedTrustAccount100.0100.0100.0100.0

alk:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedTotalIntrinsicValue us-gaap:AwardType

alk:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedTotalIntrinsicValue

us-gaap:RestrictedStock


Share
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-31
Value50373139393861473342
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedTotalIntrinsicValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

alk:TotalExpectedReliefFromPSPOfCARESAct alk:CARESActPSPProgram

alk:TotalExpectedReliefFromPSPOfCARESAct

alk:CARESPSP1


Total
Period End2021-06-30
Value0.0
Percentage of TotalExpectedReliefFromPSPOfCARESAct0.0

alk:CARESPSP2


Total
Period End2021-06-30
Value1.0
Percentage of TotalExpectedReliefFromPSPOfCARESAct0.0

alk:CARESPSP3


Total
Period End2021-06-30
Value585
Percentage of TotalExpectedReliefFromPSPOfCARESAct0.0

alk:TotalReliefFromExtensionOfPSP us-gaap:SubsequentEventType

alk:TotalReliefFromExtensionOfPSP

us-gaap:SubsequentEvent


Total
Period End2021-01-15
Value546
Percentage of TotalReliefFromExtensionOfPSP100.0

alk:UnrecordedUnconditionalPurchaseObligationOptiontoPurchaseAdditional us-gaap:AircraftType

alk:UnrecordedUnconditionalPurchaseObligationOptiontoPurchaseAdditional

alk:E175


Unrecorded
Period End2021-06-302021-03-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-09-302016-06-30
Value21.030.030.030.030.030.030.030.030.030.030.030.030.030.030.030.0
Percentage of UnrecordedUnconditionalPurchaseObligationOptiontoPurchaseAdditional100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

srt:B737Max


Unrecorded
Period End2021-06-302021-03-31
Value39.052.0
Percentage of UnrecordedUnconditionalPurchaseObligationOptiontoPurchaseAdditional185.7173.3

alk:UnsecuredTermLoanThroughPSPOfCARESAct

alk:UnsecuredTermLoanThroughPSPOfCARESAct


Unsecured
Period End2020-12-312020-09-302020-06-302019-12-31
Value2902902760.0
Percentage of UnsecuredTermLoanThroughPSPOfCARESAct100.0100.0100.00.0

alk:UnsecuredTermLoanThroughPSPOfCARESAct us-gaap:ReportingUnit, us-gaap:SubsequentEventType

alk:McGeeAirServices, us-gaap:SubsequentEvent


Unsecured
Period End2020-08-31
Value5.0
Percentage of UnsecuredTermLoanThroughPSPOfCARESAct0.0

alk:UnsecuredTermLoanThroughPSPOfCARESAct us-gaap:SubsequentEventType

us-gaap:SubsequentEvent


Unsecured
Period End2021-02-052021-01-15
Value13051
Percentage of UnsecuredTermLoanThroughPSPOfCARESAct0.00.0

dei:EntityCommonStockSharesOutstanding

dei:EntityCommonStockSharesOutstanding


Entity
Period End2021-07-302021-04-302020-10-30
Value125124123
Percentage of EntityCommonStockSharesOutstanding100.0100.0100.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-31
Value10.0112325256.09.010.0111.0-11.0-17.0-17.0-15.0-5.00.00.0-1.0-3.07.09.05.0-3.01.01.04.00.01.04.02.00.01.0-2.06.0-7.05.78.0
Percentage of AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-312010-12-31
Value-12.0-13.0-19.0-22.0-25.0-24.0-5.0-9.0-5.00.03.09.07.06.01.0-2.0-3.0-3.0-3.0-13.0-14.0-14.0-12.0-13.0-12.0-13.012-10.0-12.0-11.010.0-12.0-13.0-18.0-20.0-15.7-5.5
Percentage of AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312011-12-31
Value-485.0-492.0498453458464469422428434440420425431376287291295299278282285288291293296298169170172173403409417-423.0-380.0
Percentage of AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent


Allowance
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
Value1000000.01000000.01000000.01000000.01000000.01000000.01000000.01000000.00800000.0900000.01500000.0
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312011-09-302011-06-30
Value303308414485286309336384409367293338376328193223
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312011-09-302011-06-30
Value2715220615771426101310069781007985871852954116211301072929
Percentage of AssetsFairValueDisclosure896.0716.2380.9294.0354.2325.6291.1262.2240.8237.3290.8282.2309.0344.5553.8415.4

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312011-09-302011-06-30
Value3018251419911911129913151314139113941238114512921538145812651153
Percentage of AssetsFairValueDisclosure996.0816.2480.9394.0454.2425.6391.1362.2340.8337.3390.8382.2409.0444.5653.8515.4

us-gaap:AssetsHeldForSaleLongLivedFairValueDisclosure

us-gaap:AssetsHeldForSaleLongLivedFairValueDisclosure


Assets
Period End2020-09-30
Value219
Percentage of AssetsHeldForSaleLongLivedFairValueDisclosure100.0

us-gaap:AvailableForSaleSecurities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:AvailableForSaleSecurities

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value303308414485286309336384409367293338376330328359448416287332433412253
Percentage of AvailableForSaleSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value2623216515621419100810059649989748548388851090102110991237127611119651076109310741002
Percentage of AvailableForSaleSecurities865.7702.9377.3292.6352.4325.2286.9259.9238.1232.7286.0261.8289.9309.4335.1344.6284.8267.1336.2324.1252.4260.7396.0

us-gaap:AvailableForSaleSecurities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring, us-gaap:EquityFunds


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value5.07.07.06.05.04.06.05.00.0
Percentage of AvailableForSaleSecurities1.72.31.71.21.71.31.81.30.0

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasuryAndGovernment


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value298301407479281305330379409367293338376328
Percentage of AvailableForSaleSecurities98.397.798.398.898.398.798.298.7100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:AssetBackedSecuritiesSecuritizedLoansAndReceivables


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value330284224232197206211201189217190209231209
Percentage of AvailableForSaleSecurities108.992.254.147.868.966.762.852.346.259.164.861.861.463.7

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:CorporateDebtSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value19431515978859546537523609623514520559743726
Percentage of AvailableForSaleSecurities641.3491.9236.2177.1190.9173.8155.7158.6152.3140.1177.5165.4197.6221.3

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:ForeignGovernmentDebtSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value3119202022263125252226292843
Percentage of AvailableForSaleSecurities10.26.24.84.17.78.49.26.56.16.08.98.67.413.1

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2532932902622142131761421208792797899
Percentage of AvailableForSaleSecurities83.595.170.054.074.868.952.437.029.323.731.423.420.730.2

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:USStatesAndPoliticalSubdivisions


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value6654504629232321171410.09.010.022
Percentage of AvailableForSaleSecurities21.817.512.19.510.17.46.85.54.23.83.42.72.76.7

us-gaap:AvailableForSaleSecurities us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value29262473197619041294131413001382138312211131122314661351142715961724152712521408152614861255
Percentage of AvailableForSaleSecurities965.7802.9477.3392.6452.4425.2386.9359.9338.1332.7386.0361.8389.9409.4435.1444.6384.8367.1436.2424.1352.4360.7496.0

us-gaap:AvailableForSaleSecurities us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueMeasurementsRecurring, us-gaap:AssetBackedSecuritiesSecuritizedLoansAndReceivables


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value330284224232197206211201189217190209231209
Percentage of AvailableForSaleSecurities108.992.254.147.868.966.762.852.346.259.164.861.861.463.7

us-gaap:FairValueMeasurementsRecurring, us-gaap:CorporateDebtSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value19431515978859546537523609623514520559743726
Percentage of AvailableForSaleSecurities641.3491.9236.2177.1190.9173.8155.7158.6152.3140.1177.5165.4197.6221.3

us-gaap:FairValueMeasurementsRecurring, us-gaap:EquityFunds


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value5.07.07.06.05.04.06.05.00.0
Percentage of AvailableForSaleSecurities1.72.31.71.21.71.31.81.30.0

us-gaap:FairValueMeasurementsRecurring, us-gaap:ForeignGovernmentDebtSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value3119202022263125252226292843
Percentage of AvailableForSaleSecurities10.26.24.84.17.78.49.26.56.16.08.98.67.413.1

us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecurities


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2532932902622142131761421208792797899
Percentage of AvailableForSaleSecurities83.595.170.054.074.868.952.437.029.323.731.423.420.730.2

us-gaap:FairValueMeasurementsRecurring, us-gaap:USStatesAndPoliticalSubdivisions


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value6654504629232321171410.09.010.022
Percentage of AvailableForSaleSecurities21.817.512.19.510.17.46.85.54.23.83.42.72.76.7

us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasuryAndGovernment


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value298301407479281305330379409367293338376328
Percentage of AvailableForSaleSecurities98.397.798.398.898.398.798.298.7100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesAmortizedCost

us-gaap:AvailableForSaleSecuritiesAmortizedCost


Available
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value29002500190019001300130013001400140012001145120014891400140016001725125713981513147812601167114512541110130814821327125014031375116111191143113910811029118810731105
Percentage of AvailableForSaleSecuritiesAmortizedCost100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesCurrent

us-gaap:AvailableForSaleSecuritiesCurrent


Available
Period End2021-06-302021-03-312020-12-312020-09-302019-12-312018-12-312017-12-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value29212466197618981300113114271252140815261486125511701147126111101309148813301250140413721170113011581150109310381118
Percentage of AvailableForSaleSecuritiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value15381158775702
Percentage of AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value15391159777704
Percentage of AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value88622354
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value88612455
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value1280123111461108
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue


Available
Period End2021-06-302021-03-312020-12-312020-09-30
Value1294124611751139
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:AvailableForSaleSecuritiesDebtSecurities


Available
Period End2020-12-31
Value1976
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0

us-gaap:BankOverdrafts

us-gaap:BankOverdrafts


Bank
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value5.07.05.010.015127.011142623
Percentage of BankOverdrafts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments

us-gaap:BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments


Business
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value2000000.02000000.02000000.02000000.02000000.02000000.03000000.03000000.03000000.03000000.03000000.03000000.04000000.0
Percentage of BusinessAcquisitionsPurchasePriceAllocationSubsequentYearsRemainingAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CapitalizedContractCostNet us-gaap:BalanceSheetLocation

us-gaap:CapitalizedContractCostNet

us-gaap:PrepaidExpensesAndOtherCurrentAssets


Capitalized
Period End2020-12-312019-12-312018-12-312018-09-302018-06-302017-12-31
Value242723273124
Percentage of CapitalizedContractCostNet100.0100.0100.0100.0100.0100.0

us-gaap:CashCashEquivalentsAndShortTermInvestments

us-gaap:CashCashEquivalentsAndShortTermInvestments


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value3951354933463759280321251521161916271436123613971568152816211740192217101580322616071564132812581192131212171343151014201330144514291265125211851185114111401208
Percentage of CashCashEquivalentsAndShortTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 us-gaap:ClassOfWarrantOrRight

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1

alk:ALKCommonStockWarrant


Class
Period End2020-12-242020-04-23
Value52.2531.61
Percentage of ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1100.0100.0

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight


Class
Period End2021-06-30
Value539510.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight100.0

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight us-gaap:ClassOfWarrantOrRight

alk:PSP2Warrants


Class
Period End2021-03-31
Value255870.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight0.0

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType

alk:PSP2Warrants, us-gaap:SubsequentEvent


Class
Period End2021-04-29
Value45855.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight0.0

alk:PSP3Warrants, us-gaap:SubsequentEvent


Class
Period End2021-04-29
Value88395.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight0.0

us-gaap:ClassOfWarrantOrRightOutstanding

us-gaap:ClassOfWarrantOrRightOutstanding


Class
Period End2021-06-302021-03-31
Value1882500.01611100.0
Percentage of ClassOfWarrantOrRightOutstanding100.0100.0

us-gaap:ClassOfWarrantOrRightOutstanding us-gaap:ClassOfWarrantOrRight

alk:PSP2Warrants


Class
Period End2021-06-302021-03-31
Value305500.0255870.0
Percentage of ClassOfWarrantOrRightOutstanding16.215.9

alk:PSP3Warrants


Class
Period End2021-06-30
Value221810.0
Percentage of ClassOfWarrantOrRightOutstanding11.8

us-gaap:ContractWithCustomerLiability us-gaap:ContractWithCustomerSalesChannel

us-gaap:ContractWithCustomerLiability

alk:MileagePlanRevenue


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-31
Value234623252277218320742023199019711949191518741831177717511725166116011534
Percentage of ContractWithCustomerLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CreditCardReceivables

us-gaap:CreditCardReceivables


Credit
Period End2020-12-312019-12-31
Value83212
Percentage of CreditCardReceivables100.0100.0

us-gaap:DebtInstrumentCarryingAmount

us-gaap:DebtInstrumentCarryingAmount


Debt
Period End2021-06-302021-03-312020-12-312020-09-30
Value3211360435283857
Percentage of DebtInstrumentCarryingAmount100.0100.0100.0100.0

us-gaap:DeferredFinanceCostsNet

us-gaap:DeferredFinanceCostsNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-31
Value2333333511118.010.01112121214151516161718173.03.03.0
Percentage of DeferredFinanceCostsNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredIncomeTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value1589172311241021134711331064
Percentage of DeferredIncomeTaxLiabilities100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredRevenueCurrent

us-gaap:DeferredRevenueCurrent


Deferred
Period End2020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value663555478750794768757705693667649635
Percentage of DeferredRevenueCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredRevenueNoncurrent

us-gaap:DeferredRevenueNoncurrent


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value142415071544152015191545124011771181115811691138111011021090
Percentage of DeferredRevenueNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAndOtherLiabilitiesNoncurrent

us-gaap:DeferredTaxAndOtherLiabilitiesNoncurrent


Deferred
Period End2020-09-302020-06-302020-03-312019-12-31
Value499619665715
Percentage of DeferredTaxAndOtherLiabilitiesNoncurrent100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsGross


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value12011009614567888451431344563583526
Percentage of DeferredTaxAssetsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsInventory

us-gaap:DeferredTaxAssetsInventory


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value1715151623222018151316
Percentage of DeferredTaxAssetsInventory100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312012-12-312011-12-312010-12-31
Value2713641272890.00.0134.1
Percentage of DeferredTaxAssetsOperatingLossCarryforwards100.0100.0100.0100.0100.00.00.0100.0100.0

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsOther


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value10348435762412430212715
Percentage of DeferredTaxAssetsOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value21517917215419616716685230217179
Percentage of DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets

us-gaap:DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-31
Value15161514390.0
Percentage of DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets100.0100.0100.0100.0100.00.0

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOther


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value10658434326232221191616
Percentage of DeferredTaxLiabilitiesOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DeferredTaxLiabilitiesOtherFiniteLivedAssets

us-gaap:DeferredTaxLiabilitiesOtherFiniteLivedAssets


Deferred
Period End2020-12-312019-12-312018-12-31
Value3424160.0
Percentage of DeferredTaxLiabilitiesOtherFiniteLivedAssets100.0100.00.0

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-31
Value112612331066964128211101042919842795660
Percentage of DeferredTaxLiabilitiesPropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedBenefitObligation

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value2800240021002200
Percentage of DefinedBenefitPlanAccumulatedBenefitObligation100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value621589599588
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value-626.0-595.0-607.0-597.0
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value-5000000.0-6000000.0-8000000.0-9000000.0
Percentage of DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value51492531
Percentage of DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate us-gaap:Range, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

srt:Maximum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.580.03470.04460.03780.045
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate100.0100.0100.0100.0100.0

srt:Minimum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.430.03330.04370.03690.0429
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate94.296.098.097.695.3

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease us-gaap:Range, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease

srt:Maximum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.430.05440.0350.16510.0259
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease100.0100.0100.0100.0100.0

srt:Minimum, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value2.020.02110.02110.02110.0212
Percentage of DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease83.138.860.312.881.9

us-gaap:DefinedBenefitPlanBenefitObligation us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanBenefitObligation

us-gaap:OtherPostretirementBenefitPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value1381298285
Percentage of DefinedBenefitPlanBenefitObligation100.0100.0100.0100.0

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value29342602222523872043
Percentage of DefinedBenefitPlanBenefitObligation2126.12017.12713.42808.20.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value829
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter100.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value123
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths100.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value157
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive100.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value141
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour100.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value143
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree100.0

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-31
Value142
Percentage of DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo100.0

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets

alk:CreditBondIndexFund, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value1088100911351232
Percentage of DefinedBenefitPlanFairValueOfPlanAssets100.0100.0100.0100.0

us-gaap:CashEquivalents, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value6.0115.013
Percentage of DefinedBenefitPlanFairValueOfPlanAssets0.61.10.41.1

us-gaap:DefinedBenefitPlanEquitySecuritiesNonUs, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-31
Value384344183
Percentage of DefinedBenefitPlanFairValueOfPlanAssets35.334.116.1

us-gaap:DefinedBenefitPlanEquitySecuritiesUs, us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-31
Value914773431
Percentage of DefinedBenefitPlanFairValueOfPlanAssets84.076.638.0

us-gaap:RealEstate, us-gaap:FairValueInputsLevel3, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value9610210497
Percentage of DefinedBenefitPlanFairValueOfPlanAssets8.810.19.27.9

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:RetirementPlanType

us-gaap:FairValueInputsLevel1, us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value2386212617491973
Percentage of DefinedBenefitPlanFairValueOfPlanAssets219.3210.7154.1160.1

us-gaap:DefinedBenefitPlanFairValueOfPlanAssets us-gaap:RetirementPlanType

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-312016-12-31
Value24882239185820831846
Percentage of DefinedBenefitPlanFairValueOfPlanAssets228.7221.9163.7169.10.0

us-gaap:DefinedBenefitPlanFundedPercentage us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFundedPercentage

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value85.00.860.840.87
Percentage of DefinedBenefitPlanFundedPercentage100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanFundedStatusOfPlan us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:PensionPlansDefinedBenefit


Defined
Period End2020-12-312019-12-312018-12-312017-12-31
Value-446.0-363.0-367.0-304.0
Percentage of DefinedBenefitPlanFundedStatusOfPlan100.0100.0100.0100.0

us-gaap:DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation

us-gaap:DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation


Defined
Period End2020-12-312019-12-31
Value22071957
Percentage of DefinedBenefitPlanPensionPlanWithProjectedBenefitObligationInExcessOfPlanAssetsProjectedBenefitObligation100.0100.0

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation


Defined
Period End2020-12-312019-12-31
Value20571539
Percentage of DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation100.0100.0

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets

us-gaap:DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets


Defined
Period End2020-12-312019-12-31
Value17101545
Percentage of DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateFairValueOfPlanAssets100.0100.0

us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations us-gaap:DefinedBenefitPlanByPlanAssetCategories, us-gaap:RetirementPlanType

us-gaap:DefinedBenefitPlanWeightedAverageAssetAllocations

us-gaap:DefinedBenefitPlanEquitySecuritiesNonUs, us-gaap:PensionPlansDefinedBenefit