LUV


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

Table of contents



us-gaap:CommonStockValue

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities
us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:ComprehensiveIncomeNetOfTax
us-gaap:StatementEquityComponents

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeTaxExpenseBenefit
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:IncomeTaxesPaid
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:InterestExpenseDebt

us-gaap:InterestPaidNet

us-gaap:NetIncomeLoss
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:NonoperatingIncomeExpense

us-gaap:OperatingCostsAndExpenses

us-gaap:OperatingIncomeLoss

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherNonoperatingIncomeExpense
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax
us-gaap:DeferredRevenueArrangementType
us-gaap:ProductOrService
us-gaap:TypeOfArrangement

us-gaap:Revenues

us-gaap:Assets

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents
us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:ShortTermInvestments

us-gaap:AccountsReceivableNetCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:OperatingLeaseRightOfUseAsset

us-gaap:OtherAssetsNoncurrent

us-gaap:OtherAssets

us-gaap:AccountsPayableCurrent

us-gaap:AccruedLiabilitiesCurrent

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:LiabilitiesCurrent

us-gaap:OperatingLeaseLiabilityCurrent
us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:OtherAccruedLiabilitiesCurrent

us-gaap:TaxesPayableCurrent
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongTermDebt

us-gaap:DebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:OtherLiabilitiesNoncurrent

us-gaap:OperatingLeaseLiabilityNoncurrent
us-gaap:PropertySubjectToOrAvailableForOperatingLease
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:CumulativeEffectPeriodOfAdoption, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents
us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

us-gaap:CommonStockValue

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:TreasuryStockValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquireProductiveAssets

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:PaymentsOfDividends

us-gaap:PaymentsForRepurchaseOfCommonStock
luv:DebtDescription, us-gaap:Range, us-gaap:VariableRate
us-gaap:DebtInstrumentInterestRateStatedPercentage
luv:DebtDescription, us-gaap:VariableRate
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DeferredTaxLiabilities

us-gaap:ProceedsFromSaleOfShortTermInvestments

luv:AirTrafficLiabilityCurrentPeriodSales

luv:AirTrafficLiabilityRevenueamountsinbeginningbalance

luv:AirTrafficLiabilityRevenuefromCurrentPeriodSales

luv:AmountOfDeferredRevenueFromVendorPrepaymentThatWouldHaveBeenReceivableAtPeriodEnd

luv:AssetsConstructedForOthersDuringPeriod

luv:AssetsConstructedforOthersDuringPeriod

luv:CapitalizedFinancingItems

luv:CashRaisedNetOfFees

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramAwardedPoints
us-gaap:MajorCustomers
luv:ContractWithCustomerLiabilityLoyaltyProgramRevenueRecognized
us-gaap:DebtInstrument
luv:ConvertibleDebtConversionTermsMeasurementPeriodTradingPriceThresholdPercentage
us-gaap:DebtInstrument
luv:ConvertibleDebtConversionTermsPercentageOfSalesPriceExceedingConversionPrice

luv:CostsIncurredForVoluntarySeparation2020AndExtendedETO

luv:DeferredRevenueRelatedToVendorPrepayment
us-gaap:UnusualOrInfrequentItem
luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThrough2020

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughMarch312021

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughSeptember302020

luv:ExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020

luv:ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch312021
us-gaap:UnusualOrInfrequentItem

luv:FlightEquipmentAcquiredAgainstSupplierCredit
us-gaap:AircraftType
luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedDecember312020
us-gaap:AircraftType
luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedMarch312021
luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType
luv:LongTermPurchaseCommitmentsAdditionalMAX8s
us-gaap:AircraftType
luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType
luv:LongTermPurchaseCommitmentsAndOptionsTotal
us-gaap:AircraftType
luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType
luv:LongTermPurchaseOptionsQuantity
us-gaap:AircraftType

luv:OtherRevenueRecognizedFromPointsRedeemed
us-gaap:AircraftType
luv:OwnedAircraftDeliveredDuringTheThreeMonthsEndedMarch312021

luv:PSP3PayrollSupportProgramAmountOfGrantExpectedToBeAllocatedInThirdQuarter2021

luv:PassengerRevenueRecognizedFromPointsRedeemed

luv:PaymentsOfTerminatedInterestRateDerivativeInstruments

luv:PayrollSupportAndVoluntaryEmployeeProgramsNet
us-gaap:CounterpartyName, us-gaap:StatementScenario, us-gaap:SubsequentEventType
us-gaap:Restatement, us-gaap:ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmount

luv:Percentageofactualconsumptionhedged
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
luv:ProceedsFromGrants
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
luv:ProceedsFromGrantsNotesPayableAndWarrants

luv:ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits
us-gaap:UnusualOrInfrequentItem

luv:ProceedsFromPayrollSupportProgramGrantAllocatedToFundSalariesWagesAndBenefits

luv:ProceedsFromPayrollSupportProgramLoansAndWarrants
us-gaap:DebtInstrument
luv:RepaymentOfShortTermDebt

luv:RevenueAmountsDeferredAssociatedWithPointsAwarded

luv:SaleLeasebackCashProceedsInvesting

luv:SupplierProceeds
us-gaap:AircraftType
luv:TotalAircraftDeliveredDuringTheThreeMonthsEndedMarch312021
us-gaap:AircraftType
luv:TotalOperatingLeasedAircraftToBeDeliveredIn2020And2021FromThirdParties

luv:UnusedFundsConvertedToLoyaltyPoints

luv:VoluntarySeparationProgram2020AccrualForEmployeesWhoAcceptedAfterJune302020

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffRelievedFromAccrualForEmployeesWhoAcceptedThroughMarch312021

luv:VoluntarySeparationProgram2020ReductionForEmployeesWhoAcceptedAfterJune302020

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued
us-gaap:StatementEquityComponents

us-gaap:AircraftMaintenanceMaterialsAndRepairs
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal
us-gaap:DebtInstrument
us-gaap:DebtInstrumentRedemptionPricePercentage

us-gaap:DepreciationAndAmortization
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:DerivativeCostOfHedge
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeGainLossOnDerivativeNet
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate
luv:CommodityContractType, luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci
us-gaap:DerivativeInstrumentRisk
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings
us-gaap:DerivativeInstrumentRisk
luv:CommodityContractType, luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
us-gaap:DerivativeInstrumentRisk
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
us-gaap:DerivativeInstrumentRisk
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci
us-gaap:DerivativeInstrumentRisk

us-gaap:FuelCosts
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation
us-gaap:GainLossOnDerivativeInstrumentsNetPretax
us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments

us-gaap:IncreaseDecreaseCashCollateralFromCounterparties

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInContractWithCustomerLiability

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncrementalCommonSharesAttributableToConversionOfDebtSecurities

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestCostsCapitalizedAdjustment

us-gaap:InterestCostsIncurred

us-gaap:InvestmentIncomeInterest

us-gaap:LaborAndRelatedExpense

us-gaap:LandingFeesAndOtherRentals
luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType
us-gaap:LongTermPurchaseCommitmentMinimumQuantityRequired
us-gaap:AircraftType
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent
us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents
us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax
us-gaap:DerivativeInstrumentRisk
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax
us-gaap:DerivativeInstrumentRisk
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:DerivativeInstrumentRisk
us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax
us-gaap:DerivativeInstrumentRisk
us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossTaxPortionAttributableToParent1
us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship
us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax
us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:OtherCostAndExpenseOperating
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsToAcquireShortTermInvestments
luv:TypeOfPriorPeriodAdjustment
us-gaap:PriorPeriodReclassificationAdjustment

us-gaap:ProceedsFromConvertibleDebt

us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromIssuanceOfDebt
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
us-gaap:ProceedsFromIssuanceOfWarrants

us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromNotesPayable
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

us-gaap:ProceedsFromPaymentsForOtherFinancingActivities
us-gaap:CreditFacility
us-gaap:ProceedsFromRepaymentsOfLinesOfCredit

us-gaap:ProceedsFromStockPlans
luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax
us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome
us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax
us-gaap:StatementEquityComponents

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent
us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:RepaymentsOfSeniorDebt

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability

us-gaap:SaleAndLeasebackTransactionGainLossNet

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation
us-gaap:StatementEquityComponents

us-gaap:UnrealizedGainLossOnDerivatives

dei:EntityCommonStockSharesOutstanding

luv:AccrualforPropertyandIncomeTaxes

luv:AirTrafficLiabilityLoyaltyProgram

luv:AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices

luv:AirTrafficLiabilityTotal

luv:AircraftMaintenancePayable

luv:AssetsConstructedForOthers

luv:BusinessPartnersAndOtherSuppliers

luv:BusinessPartnersAndOtherSuppliersReceivablesCurrent

luv:CapitalCommitmentsFrom2019ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020

luv:CapitalCommitmentsFrom2020ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020

luv:ConstructionObligationNoncurrent

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgram

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramCustomerFundsExpiring

luv:ContractWithCustomerLiabilityAirTrafficLiabilityServiceRevenue

luv:ContractWithCustomerLiabilityCurrentCustomerTravelFunds
us-gaap:DebtInstrument
luv:DebtInstrumentFaceAmountNetOfFees

luv:DeferredSupplierPaymentsCurrent

luv:DeferredTaxAssetsConstructionObligation

luv:DeferredTaxAssetsOperatingLeaseLiability

luv:DeferredTaxAssetsResidualTravelFunds

luv:DefinedBenefitPlanHealthCareCostTrendRateReachedIn2028

luv:DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
luv:DerivativeAssetFairValueGrossLiabilityOffset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
luv:DerivativeAssetNoncurrentCollateralObligationToReturnCashOffset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
luv:DerivativeLiabilityFairValueAmountOffsetAgainstCollateralTotal
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
luv:DerivativeLiabilityFairValueGrossAssetOffset

luv:DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI
us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

luv:EmergencyExtendedTimeOffTotalAccrued
us-gaap:UnusualOrInfrequentItem
luv:EmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020

luv:ExtendedEmergencyTimeOffAccruedLiability

luv:ExtendedEmergencyTimeOffOtherNoncurrentLiability

luv:FinanceLeaseRightofUseAssetAccumulatedDepreciation

luv:FuelPayable
us-gaap:CounterpartyName, us-gaap:Range, us-gaap:DerivativeInstrumentRisk
luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived
us-gaap:CounterpartyName, us-gaap:Range, us-gaap:DerivativeInstrumentRisk
luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold1

luv:LeaseLiability

luv:LeaseRightofUseAsset

luv:LetterOfCreditPercentOfCollateral

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalThereafter

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalinYearSix

luv:MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther
luv:AirportProject
luv:MunicipalBondsPrincipalRemaining
luv:AirportProject
luv:NetPresentValueofPrincipalRemaining
us-gaap:OtherCommitments
us-gaap:StatementEquityComponents
luv:NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets

luv:NumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12ToBeDeliveredIn2022
us-gaap:SaleLeasebackTransactionDescription
luv:OperatingLeasesFutureMinimumPaymentsDueThereafterYear6
us-gaap:SaleLeasebackTransactionDescription
luv:OperatingLeasesFutureMinimumPaymentsDueinSixYears
us-gaap:OtherCommitments
luv:Outstandingremainingguaranteedobligation

luv:PercentageOfEmployeesRepresentedByUnionsUnderCollectiveBargainingAgreementsInNegotiations
us-gaap:OtherCommitments
luv:PrincipalRemaining
us-gaap:SubsequentEventType
luv:ProceedsFromPSP3PayrollSupportProgramGrantPerAmericanRescuePlanActOf2021ReceivedinApril2021
us-gaap:SubsequentEventType
luv:ProceedsFromPSP3PayrollSupportProgramPerAmericanRescuePlanActOf2021

luv:ProceedsFromPayrollSupportProgram

luv:ProceedsFromPayrollSupportProgramExtensionDuringFirstQuarter2021

luv:ProceedsFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsActThatWillBeUsedToOffsetSalariesWagesAndBenefitsExpensesIn1Q21
us-gaap:SubsequentEventType
luv:ProceedsFromPayrollSupportProgramExtensionGrantReceivedInJanuary2021
luv:PayrollSupportProgramAgreement, us-gaap:SubsequentEventType
luv:ProceedsFromPayrollSupportProgramExtensionReceivedInApril2021

luv:ProceedsFromPayrollSupportProgramGrantReceivedInJuly2020

luv:ProceedsFromPayrollSupportProgramGrantReceivedInSeptember2020

luv:ProceedsFromPayrollSupportProgramGrantRemainingToBeAllocatedToPayrollSupportVoluntarySeparationNet

luv:RequiredMinimumLiquidityLevelatAllTimesAfterMarch312021

luv:ResidualTravelFunds
us-gaap:AwardType
luv:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAveragePrice

luv:TerminatedInterestRateSwapLiability

luv:TotalCapitalCommitmentsShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020
us-gaap:DerivativeInstrumentRisk
luv:TotalCollateralAlreadyPostedAggregateFairValue
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
luv:TotalCollateralAlreadyReceivedAggregateFairValue
us-gaap:OtherCommitments
luv:TotalNotToExceedCostOfAirportProject

luv:TotalNumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12

luv:TotalNumberOfBoeing737MAX8FirmOrdersConvertedTo737MAX7FirmOrdersPerSupplementalAgreementNo12

luv:TotalNumberOfBoeing737MAXOptionsAddedToPurchaseAgreementPerSupplementalAgreementNo12
luv:PayrollSupportProgramAgreement, us-gaap:SubsequentEventType
luv:TotalProceedsFromPayrollSupportProgramExtensionPSP2

luv:TotalProceedsToBeProvidedToUSAirlinesFromPSP3PayrollSupportPerAmericanRescuePlanActOf2021

luv:TotalProceedsToBeProvidedToUSAirlinesFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsAct

luv:TradeReceivables

luv:UnsecuredTermLoanToBeIssuedThroughPayrollSupportProgramExtensionOfConsolidatedAppropriationsAct

luv:VendorPrepayment

luv:VoluntarySeparationProgram2020AccruedLiability

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffTotalAccrued

luv:VoluntarySeparationProgram2020OtherNoncurrentLiability
luv:Workgroup
luv:VoluntarySeparationProgram2020Participants
us-gaap:UnusualOrInfrequentItem

luv:VoluntarySeparationProgram2020TotalAccrued

luv:WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan

us-gaap:AccountsAndOtherReceivablesNetCurrent

us-gaap:AccountsPayableOtherCurrent

us-gaap:AccountsPayableTradeCurrent

us-gaap:AccrualForTaxesOtherThanIncomeTaxesCurrent

us-gaap:AccruedEmployeeBenefitsCurrent

us-gaap:AccruedSalariesCurrent

us-gaap:AccruedVacationCurrent

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

us-gaap:CapitalizedComputerSoftwareNet
us-gaap:CashAndCashEquivalents, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:CashAndCashEquivalents, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights

us-gaap:ClassOfWarrantOrRightOutstanding
luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType
luv:TypeOfAgreement, us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem
us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRightUnissued
us-gaap:CounterpartyName, us-gaap:DerivativeInstrumentRisk
us-gaap:CollateralAlreadyPostedAggregateFairValue
us-gaap:DerivativeInstrumentRisk

us-gaap:CommonStockCapitalSharesReservedForFutureIssuance

us-gaap:ContractWithCustomerLiability

us-gaap:ContractWithCustomerLiabilityNoncurrent
luv:AirportProject
us-gaap:ContractualObligation
us-gaap:OtherCommitments

us-gaap:CreditCardReceivables
luv:PayrollSupportProgramAgreement, us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrumentCarryingAmount
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:SubsequentEventType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentConvertibleConversionPrice1
us-gaap:CounterpartyName, us-gaap:LongtermDebtType, us-gaap:UnusualOrInfrequentItem
us-gaap:DebtInstrumentFaceAmount
us-gaap:DebtInstrument
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet

us-gaap:DeferredCompensationCashBasedArrangementsLiabilityCurrent

us-gaap:DeferredFinanceCostsGross

us-gaap:DeferredGainLossOnDiscontinuationOfInterestRateFairValueHedge

us-gaap:DeferredIncomeTaxLiabilities

us-gaap:DeferredRevenue

us-gaap:DeferredTaxAssetsFrequentFlierLiability

us-gaap:DeferredTaxAssetsGross

us-gaap:DeferredTaxAssetsOperatingLossCarryforwards

us-gaap:DeferredTaxAssetsOther

us-gaap:DeferredTaxAssetsStateTaxes

us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits

us-gaap:DeferredTaxLiabilitiesOther

us-gaap:DeferredTaxLiabilitiesOtherFiniteLivedAssets

us-gaap:DeferredTaxLiabilitiesPrepaidExpenses

us-gaap:DeferredTaxLiabilitiesPropertyPlantAndEquipment

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax

us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

us-gaap:DefinedBenefitPlanAmountsRecognizedInBalanceSheet

us-gaap:DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

us-gaap:DefinedBenefitPlanBenefitObligation

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

us-gaap:DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

us-gaap:DefinedBenefitPlanFundedStatusOfPlan

us-gaap:DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear

us-gaap:DefinedBenefitPlanUltimateHealthCareCostTrendRate1

us-gaap:DepositsOnFlightEquipment
luv:HedgeAdjustment, us-gaap:BalanceSheetLocation, us-gaap:HedgingDesignation
us-gaap:DerivativeAmountOfHedgedItem
luv:HedgeAdjustment, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeAssetCollateralObligationToReturnCashOffset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeAssetFairValueGrossLiability
luv:Period, us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
us-gaap:DerivativeAssetMeasurementInput
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeAssetNotSubjectToMasterNettingArrangement
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeAssets

us-gaap:DerivativeFairValueAmountOffsetAgainstCollateralNet
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeFairValueOfDerivativeAsset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:HedgingDesignation
us-gaap:CounterpartyName, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral
us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeFairValueOfDerivativeLiability
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation
us-gaap:HedgingDesignation
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeLiabilities
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeLiabilityFairValueGrossAsset
us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeLiabilityNotSubjectToMasterNettingArrangement
luv:VolumeOfFuelHedging
us-gaap:DerivativeNonmonetaryNotionalAmount

us-gaap:EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
us-gaap:DerivativeInstrumentRisk

us-gaap:FinanceLeaseLiability
luv:PropertySubjecttoorAvailableforFinanceLease

us-gaap:FinanceLeaseLiabilityCurrent
luv:PropertySubjecttoorAvailableforFinanceLease

us-gaap:FinanceLeaseLiabilityNoncurrent
luv:PropertySubjecttoorAvailableforFinanceLease
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDue
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueAfterYearFive
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueNextTwelveMonths
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueYearFive
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueYearFour
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueYearThree
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityPaymentsDueYearTwo
luv:PropertySubjecttoorAvailableforFinanceLease
us-gaap:FinanceLeaseLiabilityUndiscountedExcessAmount

us-gaap:FinanceLeaseRightOfUseAsset
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

us-gaap:FlightEquipmentGross

us-gaap:IncomeTaxesReceivable
us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:IndefiniteLivedDomesticSlotsAndRoutes

us-gaap:InterestPayableCurrent
us-gaap:BalanceSheetLocation
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:InterestRateDerivativeAssetsAtFairValue
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:InterestRateDerivativeLiabilitiesAtFairValue
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:InvestmentsFairValueDisclosure
us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementFrequency
us-gaap:PropertySubjectToOrAvailableForOperatingLease
us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

us-gaap:LettersOfCreditOutstandingAmount
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:LongtermDebtType
us-gaap:LoansPayableFairValueDisclosure

us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalAfterYearFive

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearFive

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearFour

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearThree

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalInYearTwo

us-gaap:LongTermDebtAndCapitalLeaseObligationsMaturitiesRepaymentsOfPrincipalRemainderOfFiscalYear

us-gaap:LongTermDebtAndCapitalLeaseObligationsRepaymentsOfPrincipalInNextTwelveMonths
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:NotesPayableFairValueDisclosure
us-gaap:DebtInstrument, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:LongtermDebtType

us-gaap:OperatingLeaseWeightedAverageDiscountRatePercent
us-gaap:SaleLeasebackTransactionDescription
us-gaap:OperatingLeasesFutureMinimumPaymentsDueInFiveYears
us-gaap:SaleLeasebackTransactionDescription
us-gaap:OperatingLeasesFutureMinimumPaymentsDueInFourYears
us-gaap:SaleLeasebackTransactionDescription
us-gaap:OperatingLeasesFutureMinimumPaymentsDueInThreeYears
us-gaap:SaleLeasebackTransactionDescription
us-gaap:OperatingLeasesFutureMinimumPaymentsDueInTwoYears

us-gaap:OperatingLeasesFutureMinimumPaymentsReceivableCurrent

us-gaap:OperatingLeasesFutureMinimumPaymentsReceivableInFourYears

us-gaap:OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears

us-gaap:OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears
us-gaap:SaleLeasebackTransactionDescription
us-gaap:OperatingLeasesFutureMinimumPaymentsRemainderOfFiscalYear
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:OtherAssetsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency

us-gaap:OtherAssetsMiscellaneous

us-gaap:OtherDeferredCompensationArrangementsLiabilityClassifiedNoncurrent

us-gaap:OtherReceivablesNetCurrent

us-gaap:OtherSundryLiabilitiesNoncurrent

us-gaap:PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue

us-gaap:PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months

us-gaap:PropertyPlantAndEquipmentOther
us-gaap:AircraftType
us-gaap:PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
us-gaap:AwardType
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
us-gaap:AwardType

us-gaap:TimeDeposits
us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary
us-gaap:UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchased

us-gaap:UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount

us-gaap:UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears
us-gaap:DebtInstrument
us-gaap:UnsecuredDebt
luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight
us-gaap:WarrantsAndRightsOutstanding
luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType
luv:TypeOfAgreement, us-gaap:ClassOfWarrantOrRight
us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType
us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

us-gaap:WorkersCompensationLiabilityCurrent

Plots across concepts


IncomeStatement
Other Comprehensive Income Loss Net Of Tax
Expenses
Other Nonoperating Income Expense
Balance Sheet
Intangible Assets Net Excluding Goodwill
Assets
Other Assets
Current Assets
Accounts Receivable Net Current
NonCurrent Assets
Intangible Assets Net Excluding Goodwill
PropertyPlantAndEquipmentNet
Accumulated Depreciation Depletion And Amortization Property Plant And Equipment
Liabilities
Liabilities Current
Current Liabilities
Taxes Payable Current
Noncurrent Liabilities
Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent
Stockholders Equity
Accumulated Other Comprehensive Income Loss Net Of Tax
CashFlow
Net Cash Provided By Used In Investing Activities
NetCashProvidedByUsedInOperatingActivities
Net Income Loss
NetCashProvidedByUsedInFinancingActivities
Payments For Repurchase Of Common Stock
Shares
Weighted Average Number Of Shares Outstanding Basic
NonoperatingIncomeExpense
Nonoperating Income Expense

Tables

  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:CommonStockValue █████▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▁▁▇▇888.0888.0888.0888.0888.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.00.0008080.000808808.0808.0NANANA808.0NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁615.0609.0NA590.0563.0515.0NA534.0542.0552.0NA569.0579.0588.0NA598.0605.0614.0NA625.0639.0648.0NA663.0673.0682.0NA691.0698.0707.0NA711.0722.0727.0NA740.0764.0772.0NA0.0007920.000787749.0NA0.0007470.000746744.0NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic ▄▄591.0591.0NA590.0563.0515.0NA533.0542.0551.0NA569.0578.0587.0NA597.0604.0613.0NA618.0632.0641.0NA655.0665.0674.0NA683.0690.0698.0NA703.0714.0725.0NA739.0757.0771.0NA0.0007920.00078748.0NA0.0007460.000745743.0NANANANA
 us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities us-gaap:ConvertibleDebtSecuritiesNANANA5.0NANANANANANANANANANANANANANANANANANANANANANANANANA0.0NA0.0NA6.0NA6.00.06.0NA6.00.00.0NANANANANANANANA
 us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities us-gaap:RestrictedStockUnitsRSUNANANA1.0NANANANA1.01.0NANA1.00.0NANA0.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:EarningsPerShareBasic ▄▄▂▁▁▃▅▅▆▅▅▅▅▅█▅▅▄▅▅▅▅▅▅▅▅▄▄▅▄▄▄▄▄▄▄▄▄▄▃▄▄▄▄▄▄▄▄▄▄0.590.2-1.54-1.96-1.63-0.180.981.241.370.71.171.081.270.793.190.841.240.570.850.631.30.80.830.890.910.670.280.480.670.220.30.370.310.080.110.020.30.130.2-0.180.210.010.180.270.150.010.16-0.020.12-0.12
us-gaap:EarningsPerShareDiluted ▄▄▂▁▁▃▅▅▆▅▅▅▅▅█▅▅▄▅▅▅▅▅▅▅▅▄▄▅▄▄▄▄▄▄▄▄▄▄▃▄▄▄▄▄▄▄▄▄▄0.570.19-1.54-1.96-1.63-0.180.981.231.370.71.171.081.270.793.180.841.230.570.840.621.280.790.820.880.90.660.280.480.670.220.30.370.310.080.110.020.30.130.2-0.180.210.010.180.270.150.010.16-0.020.12-0.12
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 TTM Greenblatt ROC _ _▆▅▂▁▂▄▆▇▇▆▇▇▇▆▇▇█▆▇▆█▇▇██▇▆▆▇▅▆▆▆▅▅▅▆▅▅▅▅▅▅▆▆▅▅594.0199.0-1169.0-1411.0-1127.0-110.0665.0819.0968.0505.0820.0798.0972.0616.0773.0834.01250.0658.0846.0695.01276.0944.01026.01225.01085.0780.0621.0614.0775.0215.0386.0390.0433.070.091.051.0460.022.0147.00.0002250.000207114.0216.0355.0363.054.0167.0NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:ComprehensiveIncomeNetOfTax ▅▄▁▁▂▃▅▅▅▅▄▅▆▅█▅▅▄▅▅▆▅▄▄▅▄▂▄▅▄▄▄▄▄▄▄▃▄▄▃▃▄▅▃▃▄544.0180.0-911.0-1129.0-859.0-219.0515.0566.0675.0463.0262.0729.0953.0547.02036.0630.0795.0362.0698.0517.01086.0668.0388.0345.0686.0449.0-456.0126.0588.0143.0323.0393.087.067.084.0211.0-35.0265.0216.000225-0.000546-2.5e-05346.0774.9995470.000393-1.1e-0571.0NANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments ▆▅▂▁▂▄▆▇▇▆▇▇▇▆▇▇█▆▇▆█▇▇▇▇▇▆▆▇▅▆▆▆▅▅▅▆▅▅▅▅▅▅▆▅▅▅▅▅▅502.0146.0-1331.0-1542.0-1239.0-144.0666.0819.0968.0504.0817.0786.0960.0602.0737.0791.01170.0553.0809.0618.01304.0816.0847.0933.0977.0723.0302.0525.0746.0244.0334.0419.0363.094.0125.033.0368.0159.0255.0-0.0002260.00027518.0213.0332.0184.017.0185.0-20.0107.0-107.0
us-gaap:IncomeTaxExpenseBenefit ▇▆▄▄▅▆▇▇▇▆▇▇▇▇▁▇█▇▇▇█▇▇▇█▇▆▇▇▆▆▇▇▆▆▆▇▆▇▆▆▆▇▆▆▆154.030.0-423.0-385.0-324.0-50.0153.0160.0227.0117.0163.0171.0227.0139.0-1150.0288.0424.0202.0287.0230.0484.0305.0311.0349.0369.0270.0111.0196.0281.092.0121.0160.0139.035.047.017.0140.061.0144.999958-8.6e-050.00011413.0285.9997960.0001277.2e-056.0NANANANA
us-gaap:IncomeTaxesPaid ▃▁▁▁▁▁▅▃▅▁▂▁▃▁▆▄▆▁▁▄█▂▇▆▇▂▁▃▁▁▃▃▁▁▁▁▂▁▁▁▁▁▄▁▁▁176.01.02.07.05.05.0292.0169.0314.04.0115.038.0170.04.0381.0229.0376.06.00.0264.0565.073.0465.0409.0455.0111.011.0132.012.00.0199.0124.021.02.03.02.094.01.012.9999950.04e-060.0273.9998560.0001053.9e-050.0NANANANA
 us-gaap:InterestExpenseDebt us-gaap:DerivativeInstrumentRisk,us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship,us-gaap:HedgingDesignation,us-gaap:IncomeStatementLocation us-gaap:InterestRateSwap,us-gaap:FairValueHedging,us-gaap:Nondesignated,us-gaap:InterestExpenseNANA0.04.04.04.05.06.06.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:InterestPaidNet ▇▂▇▁▃▂▂▁▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▃▂▂▂▃█▁▁▂▆▁▁▂150.017.0151.07.040.014.029.011.033.015.037.018.034.018.020.016.018.027.023.027.023.027.019.033.021.032.026.035.033.034.027.039.026.041.034.039.033.047.0184.999874.8e-054.8e-0534.0134.9998993.3e-053.3e-0534.0NANANANA
us-gaap:NetIncomeLoss ▄▄▂▁▂▃▅▅▅▅▅▅▅▅█▅▅▄▅▅▆▅▅▅▅▅▄▄▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃348.0116.0-908.0-1157.0-915.0-94.0514.0659.0741.0387.0654.0615.0733.0463.01888.0503.0746.0351.0522.0388.0820.0511.0536.0584.0608.0453.0190.0329.0465.0152.0212.0259.0224.059.078.016.0228.098.0152.0-0.000140.0001615.0131.0205.0112.011.0116.0-16.091.0-91.0
 us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome luv:UnrealizedGainOnDeferredCompensationPlanInvestment,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeNA-47.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:InterestRateSwap,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeNA1.0-2.00.01.0NANANANANANANA0.02.01.02.02.02.02.02.03.02.0NA3.03.03.0NA4.03.0NANA4.0NANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:DerivativeInstrumentRisk,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:CommodityContract,us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeNA17.0-155.031.021.0NANA15.0-2.08.0NA-15.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncomeNA-29.0-157.031.022.0NA16.017.0-1.09.01.0-14.0-12.05.068.096.0102.090.0131.0143.0152.0197.076.082.044.048.023.08.02.0NA19.028.0NANANANANANANANANANANANANANANANANANA
us-gaap:NonoperatingIncomeExpense ▅▅▄▄▅▆▆▆▆▆▆▆▆▆▆▆▅▅▆▅▆▄▄▂▅▅▂▅▆▇▅▇▅▆▇▆▅█▁▆▆▅▃▆▆-92.0-53.0-163.0-131.0-112.0-34.01.00.00.0-1.0-3.0-12.0-12.0-14.0-35.0-43.0-80.0-105.0-36.0-77.028.0-128.0-179.0-292.0-108.0-57.0-319.0-89.0-29.029.0-52.029.0-70.024.034.0-18.0-92.0137.0-369.999522-0.0004516.8e-05-96.0-242.99976-2.3e-05-0.000179NANANANANA
us-gaap:OperatingCostsAndExpenses ▄▁▄▄▂▆█▇█▇3414.01853.03181.03204.02135.04344.05065.04820.04941.04644.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingIncomeLoss ▆▅▂▁▂▄▆▇▇▆▇▇▇▆▇▇█▆▇▆█▇▇██▇▆▆▇▅▆▆▆▅▅▅▆▅▅▅▅▅▅▆▆▅▅▅▅▅594.0199.0-1169.0-1411.0-1127.0-110.0665.0819.0968.0505.0820.0798.0972.0616.0773.0834.01250.0658.0846.0695.01276.0944.01026.01225.01085.0780.0621.0614.0775.0215.0386.0390.0433.070.091.051.0460.022.0147.00.0002250.000207114.0216.0355.0363.054.0167.022.0123.0-50.0
us-gaap:OtherComprehensiveIncomeLossNetOfTax NA64.0-3.028.056.0-125.02.0-93.0-66.076.0-392.0114.0220.084.0148.0127.049.011.0176.0129.0266.0157.0-148.0-239.078.0-4.0-646.0-203.0123.0-9.0111.0134.0-137.08.06.0195.0-263.0167.0289.0-406.0NANANANANANANANANANA
us-gaap:OtherNonoperatingIncomeExpense ▆▆▄▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▅▄▆▄▃▁▄▅▁▄▅▆▅▆▅▆▆▆▄█▂▅▅▆▇▅▅▅14.048.0-63.0-35.0-32.0-28.00.0-3.0-2.0-2.0-2.0-8.0-4.0-4.0-27.0-39.0-74.0-94.0-27.0-64.043.0-114.0-162.0-272.0-88.0-32.0-293.0-66.0-3.053.0-26.059.0-47.046.062.010.0-62.0170.0-197.999649-0.0004050.00011359.0106.0001381.3e-05-0.0001464.0NANANANA
us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax ▆▃▃▃▂▆███▇███▇▇▇█▇▇▇▇▇▇▇▇▆▆▇▇▆▆▆▇▆▆▆▆▆▆▁▁▅▅▅▅▄▄▄▄▄4008.02052.02013.01793.01008.04234.05729.05639.05909.05149.05704.05575.05742.04944.05274.05303.05744.04883.05076.05139.05384.04826.04977.05318.05111.04414.04628.04800.05011.04166.04428.04545.04643.04084.04173.04309.04616.03991.04108.00.0043110.0041363103.03114.03192.03168.02630.02712.02666.02616.02357.0
us-gaap:Revenues ▆▃▃▃▂▆███▇███▇▇▇█▇▇▇▇▇▇▇▇▆▆▇▇▆▆▆▇▆▆▆▆▆▆▁▁▅▅▅▅▄▄▄▄▄4008.02052.02013.01793.01008.04234.05729.05639.05909.05149.05704.05575.05742.04944.05274.05271.05744.04883.05076.05139.05384.04826.04977.05318.05111.04414.04628.04800.05011.04166.04428.04545.04643.04084.04173.04309.04616.03991.04108.00.0043110.0041363103.03114.03192.03168.02630.02712.02666.02616.02357.0
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:Assets ██▇██▆▆▆▆▆▆▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▄▄▄▁▁▄▄38206.035493.034588.035605.035596.026885.025895.026467.026374.026459.026243.026882.026465.025503.025110.024249.023921.023763.023286.023045.022447.022241.021312.021159.021075.021163.020200.020539.020891.019976.019345.019364.019382.019197.018596.018813.018516.018826.018068.00.0178850.01894516414.015463.0NANANA14269.0NANANA
us-gaap:LiabilitiesAndStockholdersEquity ██▇██▆▆▆▆▆▆▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▅▄▄▄▄▄▁▁▄▄38206.035493.034588.035605.035596.026885.025895.026467.026374.026459.026243.026882.026465.025503.025110.024249.023921.023763.023286.023045.022447.022241.021312.021159.021075.021163.020200.020539.020891.019976.019345.019364.019382.019197.018596.018813.018516.018826.018068.00.0178850.01894516414.015463.0NANANA14269.0NANANA
us-gaap:StockholdersEquity ▇▇▇▇█▇▇▇▇▇▇█▇▇█▇▆▆▆▆▆▆▆▅▆▅▅▆▆▆▆▆▅▅▅▆▅▆▅▁▁▅▅9688.09093.08876.09769.010878.09075.09832.09931.09940.09791.09853.010153.09997.09619.010430.08800.08530.08204.08441.08047.07821.07496.07358.06968.07158.06902.06775.07429.07516.07190.07336.07013.06781.06961.06992.07002.06840.07097.06877.00.0064850.0072026587.06237.0NANANA5454.0NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:AssetsCurrent █▇▇▇▇▄▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▂▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▁▁▃▃19188.016100.015173.016133.015872.07028.05974.05650.05554.05483.05028.05601.05408.04801.04815.04280.04343.04658.04498.04839.04469.04574.04024.04573.04596.04963.04404.04985.05317.04814.04456.04773.04864.04514.04227.04652.04691.05120.04345.00.0045940.0054215329.04279.0NANANA3358.0NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue █▇▆▇▇▃▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▂▁▁▁▂▂▁▁▂▂14124.011971.011063.012109.012351.03940.02548.02488.02446.02344.01854.02104.02114.01822.01495.01460.01537.01851.01680.01966.02040.02388.01583.01740.01772.02025.01282.01832.01882.01741.01355.01333.01489.01338.01113.01168.01083.01558.0829.00.0010160.0015952039.01261.00.0010310.0009891110.01114.0NANANA
us-gaap:ShortTermInvestments █▇▇▇▆▅▅▅▅▅▆▅▅▅▆▅▅▅▅▅▄▄▅▄▄▅▅▅▆▅▆▆▆▆▆▆▇▇▇▁▁▇▇2751.02377.02271.02453.02106.01605.01524.01528.01540.01517.01835.01716.01572.01421.01778.01580.01615.01631.01625.01480.01375.01194.01468.01356.01360.01413.01706.01728.02112.01757.01797.01995.01904.01797.01857.02067.02173.02226.02315.00.002640.0027792426.02277.0NANANA1479.0NANANA
us-gaap:AccountsReceivableNetCurrent 81.0NA46.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PrepaidExpenseAndOtherAssetsCurrent █▆▅▄▄▄▅▄▅▆▅██▇▇▄▄▄▅▄▄▄▄▄▄▅▄▅▅▄▄▄▄▄▄▄▄▅▄▁▁▅▂521.0367.0295.0248.0223.0256.0287.0239.0281.0354.0310.0514.0498.0448.0460.0223.0250.0235.0310.0214.0202.0192.0188.0239.0255.0270.0232.0291.0276.0241.0250.0228.0209.0215.0210.0224.0203.0318.0238.00.000110.000264262.089.0NANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:PropertyPlantAndEquipmentGross █████████████████▇▇▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▆▆▅▅▁▁▅▅27441.027381.027574.027499.027411.027901.027713.028287.027897.027648.029256.028716.028232.028169.028229.027801.027202.026783.026464.025841.025658.025231.024685.023825.023523.023062.022513.022056.021587.021063.020820.020438.020223.019991.019497.019294.018942.018551.018421.00.0179830.01776716415.016343.0NANANA15888.0NANANA
us-gaap:AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment ████▇▇▇▇▇▇▇▆▆▆▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▅▅▅▅▅▅▅▅▅▅▁▁▄▄12199.011733.011743.011443.011164.010912.010688.010445.010164.09875.09731.09437.09166.09396.09690.09645.09523.09497.09420.09295.09364.09267.09084.08896.08663.08455.08221.08091.07860.07643.07431.07235.07059.06861.06731.06722.06600.06456.06294.00.0061490.0060465919.05765.0NANANA5254.0NANANA
us-gaap:PropertyPlantAndEquipmentNet ▆▇▇▇▇▇▇▇▇▇██████▇▇▇▇▇▇▇▆▆▆▆▆▆▆▆▆▆▆▆▆▅▅▅▁▁▅▅15242.015648.015831.016056.016247.016989.017025.017842.017733.017773.019525.019279.019066.018773.018539.018156.017679.017286.017044.016546.016294.015964.015601.014929.014860.014607.014292.013965.013727.013420.013389.013203.013164.013130.012766.012572.012342.012095.012127.00.0118340.01172110496.010578.0NANANA10634.0NANANA
us-gaap:Goodwill ███████████████████████████████████████▁▁970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.0970.00.000970.000971NA0.0NANANANANANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill ▄▄▄▄▄▄▄▄▄▄▆▆▆▆▇▇▇▇▇▇▇█████▅▅▆▆▁295.0295.0295.0295.0295.0296.0296.0311.0312.0313.0400.0403.0406.0410.0413.0416.0419.0423.0426.0430.0434.0460.0464.0469.0474.0479.0363.0366.0369.0372.0166.0NANANANANANANANANANANANANANANANANANANA
us-gaap:OperatingLeaseRightOfUseAsset ███▇▇▅▆▆▆▆▁1969.02032.01892.01767.01845.01278.01349.01352.01424.01508.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▇▆▆▆▅▅▅▅▆▆▆███▆▇▇▇▆▆▆▆▆▆▅▅▅▅▇▆▅▄▄▅▅▅▄▅▅▁▁▅▅837.0743.0722.0679.0662.0620.0577.0653.0693.0725.0720.01032.01021.0959.0786.0843.0929.0849.0774.0690.0714.0733.0717.0687.0649.0623.0534.0619.0877.0772.0530.0418.0384.0583.0633.0619.0513.0641.0626.00.0004870.000832589.0606.0NANANA277.0NANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:AccountsPayableCurrent ▇▆▅▅▅▆█▇▇▇▇▆▇▇▇▆▆▆▆▆▇▆▆▆▆▆▆▆▇▇▇▆▆▇▆▆▆▆▆▁▁1378.01094.0931.0980.0970.01043.01574.01274.01330.01412.01416.01224.01338.01243.01320.01124.01217.01214.01178.01021.01247.01153.01188.01235.01134.01145.01203.01185.01292.01299.01247.01134.01232.01250.01107.01140.01153.01208.01057.00.0010830.001049NA0.000739NANANANANANANA
us-gaap:AccruedLiabilitiesCurrent ▇▅▇▆▇▄▆▅▅▅▆▅▅▄▆▅▅▆▆▇▆██▇▅▆▅▄▅▄▄▄▄▄▄▄▄▄▄▁▁▃▃2353.01665.02259.01836.02372.01037.01749.01456.01315.01350.01749.01517.01361.01134.01777.01593.01561.01947.01985.02146.01869.02472.02591.02049.01651.01874.01565.01277.01645.01168.01229.01172.01207.01004.01102.01040.01142.01024.0996.00.0011930.00113827.0863.0NANANA729.0NANANA
us-gaap:ContractWithCustomerLiabilityCurrent █▄▁▁▄▄▃6312.04906.03790.03952.04988.05036.04457.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:LiabilitiesCurrent █▆▅▅▆▇▆▆▆▆▅▅▅▅▅▅▅▅▅▅▅▆▅▅▅▅▄▅▅▅▄▄▄▄▄▄▄▄▄▁▁▃▃12476.08182.07506.07804.09361.010241.08952.08629.08611.08723.07905.07843.07716.07162.06905.06965.07097.07458.06844.07816.07833.08253.07406.07084.06876.06903.05923.06446.07027.06441.05676.05546.05779.05411.04650.04969.05080.05047.04533.00.005320.0053184358.03305.0NANANA2695.0NANANA
us-gaap:OperatingLeaseLiabilityCurrent ▆▇▇▇█▇█▇██▁267.0292.0306.0316.0336.0330.0353.0332.0350.0361.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:OtherAccruedLiabilitiesCurrent ▆▃▆▇▅▄▆▅▆██▇▅▄▇▅▅▅▅▅▅▅▅▅▆▄▅▆▅▅▅▅▅▅▅▄▅▅▆▁▁▅▅292.0122.0257.0327.0233.0180.0255.0249.0260.0383.0388.0332.0200.0158.0346.0228.0205.0202.0237.0219.0210.0205.0246.0219.0258.0192.0236.0255.0233.0217.0223.0203.0202.0198.0212.0192.0227.0211.0278.00.0002950.000302225.0211.0NANANA187.0NANANA
us-gaap:TaxesPayableCurrent ▇▅▁▁▁▂▆▅▇█▆▅██▆▅▇█▅▅▇▇▅▄▆▆▄▄▆▆▄266.0190.049.041.038.066.0227.0188.0269.0291.0220.0196.0277.0282.0203.0180.0266.0280.0184.0165.0239.0246.0179.0157.0234.0229.0163.0142.0214.0218.0146.0NANANA128.0NANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A10PayrollSupportProgramLoanDue2030,us-gaap:UnsecuredDebt976.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A10PayrollSupportProgramLoanDue2031,us-gaap:UnsecuredDebt566.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A10PayrollSupportProgramLoanDueApril2031,us-gaap:UnsecuredDebt526.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A1250ConvertibleSeniorNotesDue2025,us-gaap:ConvertibleDebt█▄▁1982.01963.01945.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A160TermLoanAgreementPayableThrough2028,us-gaap:NotesPayableToBanks171.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A345UnsecuredSeniorNotesDue2027,us-gaap:UnsecuredDebt300.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A4750UnsecuredNotesDue2023,us-gaap:UnsecuredDebt1250.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A5125NotesDue2027,us-gaap:UnsecuredDebt2000.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:A5250UnsecuredNotesDue2025,us-gaap:UnsecuredDebt1550.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:DebenturesDue2027,us-gaap:UnsecuredDebt118.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:TermLoanAgreementDue2025,us-gaap:NotesPayableToBanks106.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:TermLoanAgreementDue2026,us-gaap:NotesPayableToBanks149.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:TotalPassThroughCertificates,us-gaap:EnhancedEquipmentTrustCertificate105.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:UnsecuredSeniorNotesDue2022,us-gaap:UnsecuredDebt300.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:UnsecuredSeniorNotesDue2026,us-gaap:UnsecuredDebt300.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebt us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:UnsecuredSeniorNotesDue2030,us-gaap:UnsecuredDebt500.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:DebtAndCapitalLeaseObligations NANA10381.0NANANA2678.0NANANA3396.0NANANA3693.0NANANA3410.0NANANA3198.0NANANA2713.0NANANA2842.0NANANA3175.0NANANANANANANANANANANANANANANA
us-gaap:LongTermDebtAndCapitalLeaseObligations ▇███▇▁▁▁▁▂▂▂▂▂▂▂▂▂▂▁▁▁▂▁▁▁▁▁▁▁▁9188.010546.010111.010135.08905.02288.01846.02398.02449.02602.02771.03100.03155.03227.03320.02763.02788.02781.02821.02323.02391.02355.02541.02381.02411.02416.02434.02125.02153.02172.02191.0NANANA2883.0NANANANANANANANANANANANANANANA
us-gaap:DeferredIncomeTaxLiabilitiesNet ▂▁▁▃▆▇█1688.01660.01634.01824.02114.02278.02364.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent ███▆▆▆▆▅▅▅▅▆▆▆▅▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▄▄▃▃▃▃▃▃▁▁432.0430.0428.0339.0299.0294.0288.0245.0240.0235.0232.0294.0288.0282.0275.0274.0267.0261.0256.0215.0211.0206.0201.0179.0176.0172.0169.0143.0144.0140.0138.0169.0162.0154.0148.0116.0112.0109.0107.00.0001059.8e-05NA9.1e-05NANANANANANANA
us-gaap:OtherLiabilitiesNoncurrent ▇▇██▅▅▅▅▅▄▅▅▅▅▅▅▅▅▅▅▅▅▅▆▅▇█▅▅▅▅██▇▇▇▆▆▆▁▁▄▄1120.01123.01247.01233.0722.0694.0706.0644.0639.0608.0650.0748.0692.0706.0707.0713.0708.0703.0728.0661.0681.0703.0760.0931.0708.01095.01255.0658.0710.0726.0771.01198.01211.01153.01124.01114.0945.0924.0910.00.0009260.000838460.0465.0NANANA493.0NANANA
us-gaap:OperatingLeaseLiabilityNoncurrent ██▇▇▇▅▅▅▅▆▁1679.01722.01562.01424.01486.0936.0978.01014.01072.01150.00.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease us-gaap:PropertySubjectToOperatingLeaseNANA253.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease us-gaap:PropertySubjectToOperatingLeaseNANA219.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease us-gaap:PropertySubjectToOperatingLeaseNANA193.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease us-gaap:PropertySubjectToOperatingLeaseNANA156.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease us-gaap:PropertySubjectToOperatingLeaseNANA1156.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:StockholdersEquity ▇▇▇▇█▇▇▇▇▇▇█▇▇█▇▆▆▆▆▆▆▆▅▆▅▅▆▆▆▆▆▅▅▅▆▅▆▅▁▁▅▅9688.09093.08876.09769.010878.09075.09832.09931.09940.09791.09853.010153.09997.09619.010430.08800.08530.08204.08441.08047.07821.07496.07358.06968.07158.06902.06775.07429.07516.07190.07336.07013.06781.06961.06992.07002.06840.07097.06877.00.0064850.0072026587.06237.0NANANA5454.0NANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents luv:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesInterestRateDerivativeNA-53.0-66.0-71.0-74.0-75.0-33.0-53.0-33.0-14.00.0-1.0-2.0-4.0-7.0-11.0-13.0-15.0-18.0-26.0-32.0NA-30.0NANANA-45.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents luv:OtherComprehensiveIncomeOtherChangesNetOfTaxNANA91.069.055.022.059.047.045.039.025.043.036.033.033.026.022.020.020.011.06.06.06.03.08.0NA8.0NANANA8.0NANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents us-gaap:AccumulatedDefinedBenefitPlansAdjustmentNA-43.0-43.020.020.020.020.058.058.058.058.0-9.0-9.0-9.0-9.0-14.0-14.0-14.0-14.022.022.022.022.0NANANA41.0NANANA65.0NANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesNA12.0-119.0-151.0-170.0-209.0-125.0-135.0-31.042.0-56.0504.0365.083.03.0-216.0-412.0-485.0-499.0-799.0-993.0NA-1666.0NANANA-1177.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents us-gaap:AccumulatedNetUnrealizedInvestmentGainLossNA24.032.031.039.056.018.020.0-9.0-29.0-7.0-125.0-92.0-25.0-8.079.0154.0182.0188.0293.0369.0NA617.0NANANA435.0NANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents us-gaap:AociIncludingPortionAttributableToNoncontrollingInterestNA-60.0-105.0-102.0-130.0-186.0-61.0-63.030.096.020.0412.0298.078.012.0-136.0-263.0-312.0-323.0-499.0-628.0-894.0-1051.0-903.0-664.0NA-738.0NANANA-3.0NANANANANANANANANANANANANANANANANANANA
us-gaap:CommonStockValue █████▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▇▁▁▇▇888.0888.0888.0888.0888.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.0808.00.0008080.000808808.0808.0NANANA808.0NANANA
us-gaap:AdditionalPaidInCapitalCommonStock █████▄▄▄▄▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▃▁▁▃▃4269.04220.04191.04175.04159.01582.01581.01554.01534.01513.01510.01485.01469.01452.01451.01436.01422.01419.01410.01402.01383.01387.01374.01330.01319.01329.01315.01280.01263.01256.01231.01205.01201.01214.01210.01228.01224.01225.01222.00.0012220.0012191186.01183.0NANANA1216.0NANANA
us-gaap:RetainedEarningsAccumulatedDeficit ▇▇▇▇█████▇▇▇▇▇▇▆▆▆▅▅▅▅▅▄▄▄▄▄▄▄▄▃▃▃▃▃▃▃▃▁▁▃▃15260.014912.014777.015685.016842.017757.017945.017525.016962.016320.015967.015402.014878.014238.014621.012806.012378.011708.011418.010957.010631.09872.09409.08922.08387.07829.07416.07266.06979.06555.06431.06246.06015.05818.05768.05700.05692.05486.05395.00.0052510.0053985399.05399.0NANANA4971.0NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▇▆▆▆▅▅▆▆▆▆▆█▇▆▆▅▅▅▄▄▃▂▁▂▃▂▂▆▇▆▆▅▅▅▅▅▄▆▅▆▆▆▅136.0-60.0-105.0-102.0-130.0-186.0-61.0-63.030.096.020.0412.0298.078.012.0-136.0-263.0-312.0-323.0-499.0-628.0-894.0-1051.0-903.0-664.0-742.0-738.0-92.0111.0-12.0-3.0-114.0-248.0-111.0-119.0-125.0-320.0-57.0-224.0-0.000513-0.00010779.0-262.0NANANA-578.0NANANA
us-gaap:TreasuryStockValue ███████▇▇▇▇▆▆▆▅▅▅▅▄▄▄▄▃▃▃▃▃▃▃▂▂▂▂▂▂▂▂▂▂▂▂▁▁10865.010867.010875.010877.010881.010886.010441.09893.09394.08946.08452.07954.07456.06957.06462.06114.05815.05419.04872.04621.04373.03677.03182.03189.02692.02322.02026.01833.01645.01417.01131.01132.0995.0768.0675.0609.0564.0365.0324.00.0002830.000116-885.0-891.0NANANA-963.0NANANA
us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue █▁16.014.0NANA-2.09.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities █▅▂▁▅▃▅▆▆▆▆▆▇▆▅▆▅▇▅▅▆▇▄▅▅▇▄▄▆▆▄▄▅▆▄▄▄▆▇▃▃▆▇▃▃▄2005.0645.0-596.0-1050.0897.0-377.0824.01091.0966.01105.0989.01271.01631.01002.0563.0996.0746.01625.0709.0856.01112.01616.0324.0836.0627.01452.0204.0240.01338.01119.0289.0428.0778.0983.0231.0464.0145.01225.01384.999015-0.0002180.000237965.01560.9987080.0003850.00054373.0NANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▆▇▅█▇▇▅▅▇▄▄▄▆▃▄▄▄▃▄▄▆▂▅▅▅▄▆▃▅▅▅▅▄▆▅▅▆▂▇▇▆▁▇▇▅-469.0-201.091.0-434.0332.0-5.0144.0-359.0-252.0164.0-668.0-604.0-694.0-73.0-735.0-620.0-584.0-470.0-839.0-584.0-674.0-175.0-946.0-259.0-407.0-302.0-468.0-44.0-857.0-358.0-254.0-359.0-300.0-472.0-189.0-277.0-355.0-12.0-1050.999043-0.000137-0.000589-231.0-1264.998755-0.000312-0.00061-322.0NANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▂▁▃█▃▁▁▁▁▁▁▁▁▂▁▁▁▂▂▁▁▂▁▁▁▂▂▂▂▂▂▂▂▂▂▂▁▁▂▂▂▂▂▂▂617.0464.0-541.01242.07182.01774.0-908.0-690.0-612.0-779.0-571.0-677.0-645.0-602.0207.0-453.0-476.0-984.0-156.0-346.0-786.0-636.0465.0-609.0-473.0-407.0-286.0-246.0-340.0-375.0-13.0-225.0-327.0-286.0-97.0-102.0-265.0-484.0-765.999727-0.000224-9.2e-0544.0-148.99987-3.1e-05-5.1e-05-55.0NANANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▃▂▁▂█▃▂▂▂▂2153.0908.0-1046.0-242.08411.01392.060.042.0102.0490.0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities █▅▂▁▅▃▅▆▆▆▆▆▇▆▅▆▅▇▅▅▆▇▄▅▅▇▄▄▆▆▄▄▅▆▄▄▄▆▇▃▃▆▇▃▃▄2005.0645.0-596.0-1050.0897.0-377.0824.01091.0966.01105.0989.01271.01631.01002.0563.0996.0746.01625.0709.0856.01112.01616.0324.0836.0627.01452.0204.0240.01338.01119.0289.0428.0778.0983.0231.0464.0145.01225.01384.999015-0.0002180.000237965.01560.9987080.0003850.00054373.0NANANANA
us-gaap:NetIncomeLoss ▄▄▂▁▂▃▅▅▅▅▅▅▅▅█▅▅▄▅▅▆▅▅▅▅▅▄▄▅▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▃348.0116.0-908.0-1157.0-915.0-94.0514.0659.0741.0387.0654.0615.0733.0463.01888.0503.0746.0351.0522.0388.0820.0511.0536.0584.0608.0453.0190.0329.0465.0152.0212.0259.0224.059.078.016.0228.098.0152.0-0.000140.0001615.0131.0205.0112.011.0116.0-16.091.0-91.0
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▄▆▇▅█▇▇▅▅▇▄▄▄▆▃▄▄▄▃▄▄▆▂▅▅▅▄▆▃▅▅▅▅▄▆▅▅▆▂▇▇▆▁▇▇▅-469.0-201.091.0-434.0332.0-5.0144.0-359.0-252.0164.0-668.0-604.0-694.0-73.0-735.0-620.0-584.0-470.0-839.0-584.0-674.0-175.0-946.0-259.0-407.0-302.0-468.0-44.0-857.0-358.0-254.0-359.0-300.0-472.0-189.0-277.0-355.0-12.0-1050.999043-0.000137-0.000589-231.0-1264.998755-0.000312-0.00061-322.0NANANANA
us-gaap:PaymentsToAcquireProductiveAssets ▁▁▁▁▁▂▃▄▂▂▅▅▅▄▅▆▅▄▇▅▅▄█▂▄▆▄▄▅▄▄▃▂▅95.095.090.089.0113.0224.0261.0375.0230.0160.0538.0454.0521.0409.0520.0638.0551.0414.0674.0464.0462.0438.0810.0230.0428.0573.0408.0433.0500.0407.0438.0268.0193.0534.0NANANANANANANANANANANANANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ▂▂▁▃█▃▁▁▁▁▁▁▁▁▂▁▁▁▂▂▁▁▂▁▁▁▂▂▂▂▂▂▂▂▂▂▂▁▁▂▂▂▂▂▂▂617.0464.0-541.01242.07182.01774.0-908.0-690.0-612.0-779.0-571.0-677.0-645.0-602.0207.0-453.0-476.0-984.0-156.0-346.0-786.0-636.0465.0-609.0-473.0-407.0-286.0-246.0-340.0-375.0-13.0-225.0-327.0-286.0-97.0-102.0-265.0-484.0-765.999727-0.000224-9.2e-0544.0-148.99987-3.1e-05-5.1e-05-55.0NANANANA
us-gaap:PaymentsOfDividends NANA0.00.00.0188.00.096.098.0178.00.091.093.0148.00.075.076.0123.00.062.063.096.0NA49.050.081.0NANANANANANANANANANANANA13.9999863e-063e-06-7.0-13.0000133e-063e-06-7.0NANANANA
us-gaap:PaymentsForRepurchaseOfCommonStock NANA0.00.00.0451.0550.0500.0450.0500.0500.0500.0500.0500.0350.0300.0400.0550.0300.0250.0700.0500.00.0500.0380.0300.0200.0200.0240.0315.039.0150.0251.0100.075.050.0225.050.0224.9998250.0001750.00.00.00.00.0NANANANANA
  2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription,us-gaap:Range,us-gaap:VariableRate luv:Amended364DayTermLoanCreditFacility,srt:Minimum,us-gaap:BaseRateNANA1e-061e-061e-081e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription,us-gaap:Range,us-gaap:VariableRate luv:Amended364DayTermLoanCreditFacility,srt:Minimum,us-gaap:LondonInterbankOfferedRateLIBORNANA1e-061e-061e-081e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription,us-gaap:VariableRate luv:Amended364DayTermLoanCreditFacility,luv:NewYorkFedBankRateNANA5e-075e-075e-095e-09NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription,us-gaap:VariableRate luv:Amended364DayTermLoanCreditFacility,us-gaap:LondonInterbankOfferedRateLIBORNANA1e-061e-061e-081e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument luv:TermLoanAgreementDue2026NANA1.34e-06NANANA3.03e-08NANANA3.8800000000000003e-08NANANA2.67e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:CARESActUnsecuredLoan,us-gaap:UnsecuredDebtNANA1e-061e-061e-08NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType luv:PayrollSupportProgramExtensionUnsecuredLoan,us-gaap:UnsecuredDebtNA1e-06NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA

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
Value8888888888888888088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088080.0008080.000808808808808
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 Assets2.32.52.62.52.53.03.13.13.13.13.13.03.13.23.23.33.43.43.53.53.63.63.83.83.83.84.03.93.94.04.24.24.24.24.34.34.44.34.54.54.34.95.25.7

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
Value6156095905635155345425525695795885986056146256396486636736826916987077117227277407647720.0007920.0007877490.0007470.000746744
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
Value5915915905635155335425515695785875976046136186326416556656746836906987037147257397577710.0007920.000787480.0007460.000745743
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

Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecurities

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:ConvertibleDebtSecurities


Antidilutive
Period End2020-09-302014-03-312013-09-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value5.00.00.06.06.00.06.06.00.00.0
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.00.00.0100.0100.00.0100.0100.00.00.0

us-gaap:RestrictedStockUnitsRSU


Antidilutive
Period End2020-09-302019-06-302019-03-312018-06-302018-03-312017-06-30
Value1.01.01.01.00.00.0
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount20.00.00.00.00.00.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.590.2-1.54-1.96-1.63-0.180.981.241.370.71.171.081.270.793.190.841.240.570.850.631.30.80.830.890.910.670.280.480.670.220.30.370.310.080.110.020.30.130.2-0.180.210.010.180.270.150.010.16-0.020.12-0.12
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


Earnings
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value0.570.19-1.54-1.96-1.63-0.180.981.231.370.71.171.081.270.793.180.841.230.570.840.621.280.790.820.880.90.660.280.480.670.220.30.370.310.080.110.020.30.130.2-0.180.210.010.180.270.150.010.16-0.020.12-0.12
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Comprehensive Income Net Of Tax

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


Comprehensive
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value544180-911.0-1129.0-859.0-219.051556667546326272995354720366307953626985171086668388345686449-456.0126588143323393876784211-35.0265216-0.000546-2.5e-053467740.000393-1.1e-0571
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.68.8-45.3-63.0-85.2-5.29.010.011.49.04.613.116.611.138.611.913.87.413.810.120.213.87.86.513.410.2-9.92.611.73.47.38.61.91.62.04.9-0.86.65.3-12.7-0.611.224.90.0-0.02.7

us-gaap:ComprehensiveIncomeNetOfTax us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


Comprehensive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value196642856-125.0-93.0-66.07611422084
Percentage of ComprehensiveIncomeNetOfTax36.035.6-2.5-6.557.1-16.4-9.816.415.623.115.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.93.11.65.6-3.0-1.6-1.11.52.03.81.7
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Comprehensive
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value348116-1157.0-915.0-94.0659741387615733463
Percentage of ComprehensiveIncomeNetOfTax64.064.4102.5106.542.9116.4109.883.684.476.984.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.75.7-64.5-90.8-2.211.712.57.511.012.89.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.0

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

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments


Income
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value502146-1331.0-1542.0-1239.0-144.0666819968504817786960602737791117055380961813048168479339777233025257462443344193639412533368159255-0.0002260.0002751821333218417185-20.0107-107.0
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax12.57.1-66.1-86.0-122.9-3.411.614.516.49.814.314.116.712.214.014.920.411.315.912.024.216.917.017.519.116.46.510.914.95.97.59.27.82.33.00.88.04.06.2-5.26.60.66.810.45.80.66.8-0.84.1-4.5

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
Value15430-423.0-385.0-324.0-50.0153160227117163171227139-1150.02884242022872304843053113493692701111962819212116013935471714061144-8.6e-050.000114132850.0001277.2e-056.0
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 RevenueFromContractWithCustomerExcludingAssessedTax3.81.5-21.0-21.5-32.1-1.22.72.83.82.32.93.14.02.8-21.85.47.44.15.74.59.06.36.26.67.26.12.44.15.62.22.73.53.00.91.10.43.01.53.5-2.02.80.49.20.00.00.2

us-gaap:IncomeTaxExpenseBenefit luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

luv:UnrealizedGainOnDeferredCompensationPlanInvestment, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Income
Period End2021-03-31
Value13
Percentage of IncomeTaxExpenseBenefit43.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:UnrealizedGainOnDeferredCompensationPlanInvestment us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Income
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value-5.04.09.07.0-5.0-4.00.0-3.05.0
Percentage of IncomeTaxExpenseBenefit-16.7-0.9-2.3-2.210.0-2.50.0-2.62.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-0.20.20.50.7-0.1-0.10.0-0.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Income
Period End2021-06-30
Value3.0
Percentage of IncomeTaxExpenseBenefit1.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.0

Income Taxes Paid

us-gaap:IncomeTaxesPaid

us-gaap:IncomeTaxesPaid


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
Value1761.02.07.05.05.02921693144.0115381704.03812293766.00.02645657346540945511111132120.0199124212.03.02.0941.0120.04e-060.02730.0001053.9e-050.0
Percentage of IncomeTaxesPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.00.0100.0100.0100.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax4.40.00.10.40.50.15.13.05.30.12.00.73.00.17.24.36.50.10.05.110.51.59.37.78.92.50.22.80.20.04.52.70.50.00.10.02.00.00.30.00.10.08.80.00.00.0

Interest Expense Debt

us-gaap:InterestExpenseDebt us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:HedgingDesignation, us-gaap:IncomeStatementLocation

us-gaap:InterestExpenseDebt

us-gaap:InterestRateSwap, us-gaap:FairValueHedging, us-gaap:Nondesignated, us-gaap:InterestExpense


Interest
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.04.04.04.05.06.06.0
Percentage of InterestExpenseDebt0.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.00.20.40.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:InterestRateSwap us-gaap:FairValueHedging us-gaap:Nondesignated us-gaap:InterestExpense0.00.00.00.00.00.00.0

Interest Paid Net

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


Interest
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value150171517.0401429113315371834182016182723272327193321322635333427392641343933471844.8e-054.8e-05341343.3e-053.3e-0534
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.70.87.50.44.00.30.50.20.60.30.60.30.60.40.40.30.30.60.50.50.40.60.40.60.40.70.60.70.70.80.60.90.61.00.80.90.71.24.51.11.21.14.30.00.01.3

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value348116-908.0-1157.0-915.0-94.0514659741387654615733463188850374635152238882051153658460845319032946515221225922459781622898152-0.000140.0001615.013120511211116-16.091-91.0
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.75.7-45.1-64.5-90.8-2.29.011.712.57.511.511.012.89.435.89.513.07.210.37.615.210.610.811.011.910.34.16.99.33.64.85.74.81.41.90.44.92.53.7-3.23.90.24.26.43.50.44.3-0.63.5-3.9

us-gaap:NetIncomeLoss us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Net
Period End2021-06-30
Value9.0
Percentage of NetIncomeLoss2.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.0

us-gaap:InterestRateContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Net
Period End2021-06-30
Value1.0
Percentage of NetIncomeLoss0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:InterestRateContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-06-30
Value10.0
Percentage of NetIncomeLoss2.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.0

Net Income Loss Available To Common Stockholders Basic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

luv:UnrealizedGainOnDeferredCompensationPlanInvestment, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-03-31
Value-47.0
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:UnrealizedGainOnDeferredCompensationPlanInvestment us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.0

us-gaap:InterestRateSwap, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-03-312020-12-312020-09-302020-06-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302013-09-30
Value1.0-2.00.01.00.02.01.02.02.02.02.02.03.02.03.03.03.04.03.04.0
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic-2.10.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0-0.10.00.10.00.00.00.00.00.00.00.00.10.00.10.10.10.10.10.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:InterestRateSwap us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-03-312020-12-312020-09-302020-06-302019-09-302019-06-302019-03-312018-09-30
Value17-155.0312115-2.08.0-15.0
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic-36.20.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.8-7.71.72.10.3-0.00.2-0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.0

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-03-312020-12-312020-09-302020-06-302019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-312013-09-30
Value-29.0-157.031221617-1.09.01.0-14.0-12.05.068961029013114315219776824448238.02.01928
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic61.70.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-1.4-7.81.72.20.30.3-0.00.20.0-0.3-0.20.11.31.81.81.82.62.82.84.11.51.50.91.10.50.20.00.40.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Nonoperating Income Expense

us-gaap:NonoperatingIncomeExpense

us-gaap:NonoperatingIncomeExpense


Nonoperating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value-92.0-53.0-163.0-131.0-112.0-34.01.00.00.0-1.0-3.0-12.0-12.0-14.0-35.0-43.0-80.0-105.0-36.0-77.028-128.0-179.0-292.0-108.0-57.0-319.0-89.0-29.029-52.029-70.02434-18.0-92.0137-369.999522-0.0004516.8e-05-96.0-242.99976-2.3e-05-0.000179
Percentage of NonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax-2.3-2.6-8.1-7.3-11.1-0.80.00.00.0-0.0-0.1-0.2-0.2-0.3-0.7-0.8-1.4-2.2-0.7-1.50.5-2.7-3.6-5.5-2.1-1.3-6.9-1.9-0.60.7-1.20.6-1.50.60.8-0.4-2.03.4-9.0-10.51.6-3.1-7.8-0.0-0.0

Operating Costs And Expenses

us-gaap:OperatingCostsAndExpenses

us-gaap:OperatingCostsAndExpenses


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value3414185331813204213543445065482049414644
Percentage of OperatingCostsAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax85.290.3158.0178.7211.8102.688.485.583.690.2

Operating Income Loss

us-gaap:OperatingIncomeLoss

us-gaap:OperatingIncomeLoss


Operating
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value594199-1169.0-1411.0-1127.0-110.066581996850582079897261677383412506588466951276944102612251085780621614775215386390433709151460221470.0002250.0002071142163553635416722123-50.0
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax14.89.7-58.1-78.7-111.8-2.611.614.516.49.814.414.316.912.514.715.721.813.516.713.523.719.620.623.021.217.713.412.815.55.28.78.69.31.72.21.210.00.63.65.25.03.76.911.111.52.16.20.84.7-2.1

Other Comprehensive Income Loss Net Of Tax

us-gaap:OtherComprehensiveIncomeLossNetOfTax

us-gaap:OtherComprehensiveIncomeLossNetOfTax


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value64-3.02856-125.02.0-93.0-66.076-392.0114220841481274911176129266157-148.0-239.078-4.0-646.0-203.0123-9.0111134-137.08.06.0195-263.0167289-406.0
Percentage of OtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.1-0.11.65.6-3.00.0-1.6-1.11.5-6.92.03.81.72.82.40.90.23.52.54.93.3-3.0-4.51.5-0.1-14.0-4.22.5-0.22.52.9-3.00.20.14.5-5.74.27.0-9417768.5

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
Value1448-63.0-35.0-32.0-28.00.0-3.0-2.0-2.0-2.0-8.0-4.0-4.0-27.0-39.0-74.0-94.0-27.0-64.043-114.0-162.0-272.0-88.0-32.0-293.0-66.0-3.053-26.059-47.0466210.0-62.0170-197.999649-0.0004050.000113591061.3e-05-0.0001464.0
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.32.3-3.1-2.0-3.2-0.70.0-0.1-0.0-0.0-0.0-0.1-0.1-0.1-0.5-0.7-1.3-1.9-0.5-1.20.8-2.4-3.3-5.1-1.7-0.7-6.3-1.4-0.11.3-0.61.3-1.01.11.50.2-1.34.3-4.8-9.42.71.93.40.0-0.00.2

us-gaap:OtherNonoperatingIncomeExpense luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-31
Value6.0-77.022142.0
Percentage of OtherNonoperatingIncomeExpense12.5122.2-62.9-43.8-7.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.3-3.81.21.40.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.00.00.00.00.0

Revenue From Contract With Customer Excluding Assessed Tax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value4008205220131793100842345729563959095149570455755742494452745303574448835076513953844826497753185111441446284800501141664428454546434084417343094616399141080.0043110.004136310331143192316826302712266626162357
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:DeferredRevenueArrangementType

luv:ChaseAndOtherPartnerAgreements


Revenue
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value280241282256321316329336319244290292271233273
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.612.015.725.47.65.55.85.76.24.35.25.15.54.45.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.612.015.725.47.65.55.85.76.24.35.25.15.54.45.1
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:ChaseAndOtherPartnerAgreements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductOrService

luv:PassengerAncillarySoldSeparately


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value14580696661164189173182167176154165146154146
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.63.93.43.76.13.93.33.13.13.23.12.82.93.02.92.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax3.63.93.43.76.13.93.33.13.13.23.12.82.93.02.92.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:PassengerAncillarySoldSeparately100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:PassengerLoyaltyAirTransportation


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value54927825620581461673657622535605623588491539616
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.713.512.711.48.010.911.711.710.510.410.611.210.29.910.211.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax13.713.512.711.48.010.911.711.710.510.410.611.210.29.910.211.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:PassengerLoyaltyAirTransportation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:PassengerRevenueNonLoyalty


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value287513541337118356232204452440046834043453744174605394842014182
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax71.766.066.466.055.876.177.778.079.378.579.579.280.279.979.778.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax71.766.066.466.055.876.177.778.079.378.579.579.280.279.979.778.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax luv:PassengerRevenueNonLoyalty100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CargoAndFreight


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value50434341383943424442454344424542
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.22.12.12.33.80.90.80.70.70.80.80.80.80.80.90.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax1.22.12.12.33.80.90.80.70.70.80.80.80.80.80.90.8
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CargoAndFreight100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Passenger


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value356917121662145470438455314523054874745531851945358458548944944
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax89.083.482.681.169.890.892.892.792.992.293.293.293.392.792.893.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax89.083.482.681.169.890.892.892.792.992.293.293.293.392.792.893.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:Passenger100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProductAndServiceOther


Revenue
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value389297308298266350373367378362341338340317319317
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.714.515.316.626.48.36.56.56.47.06.06.15.96.46.06.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax9.714.515.316.626.48.36.56.56.47.06.06.15.96.46.06.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ProductAndServiceOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:TypeOfArrangement

us-gaap:CollaborativeArrangementTransactionWithPartyToCollaborativeArrangement


Revenue
Period End2021-06-302020-06-30
Value352256
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.825.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.825.4
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CollaborativeArrangementTransactionWithPartyToCollaborativeArrangement100.0100.0

Revenues

us-gaap:Revenues

us-gaap:Revenues


Revenues
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value4008205220131793100842345729563959095149570455755742494452745271574448835076513953844826497753185111441446284800501141664428454546434084417343094616399141080.0043110.004136310331143192316826302712266626162357
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.099.4100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value3820635493345883560535596268852589526467263742645926243268822646525503251102424923921237632328623045224472224121312211592107521163202002053920891199761934519364193821919718596188131851618826180680.0178850.018945164141546314269
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

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3820635493345883560535596268852589526467263742645926243268822646525503251102424923921237632328623045224472224121312211592107521163202002053920891199761934519364193821919718596188131851618826180680.0178850.018945164141546314269
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value9688909388769769108789075983299319940979198531015399979619104308800853082048441804778217496735869687158690267757429751671907336701367816961699270026840709768770.0064850.00720265876237545449416929
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets25.425.625.727.430.633.838.037.537.737.037.537.837.837.741.536.335.734.536.234.934.833.734.532.934.032.633.536.236.036.037.936.235.036.337.637.236.937.738.136.338.040.140.338.20.00.0

us-gaap:StockholdersEquity us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccountingStandardsUpdate201601, us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-31
Value-19.0
Percentage of StockholdersEquity-0.2
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccountingStandardsUpdate201601 us-gaap:AccumulatedOtherComprehensiveIncome0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccountingStandardsUpdate201601, us-gaap:RetainedEarnings


Stockholders
Period End2020-12-31
Value19
Percentage of StockholdersEquity0.2
Percentage of Assets0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccountingStandardsUpdate201601 us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquity us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementEquityComponents

srt:CumulativeEffectPeriodOfAdoptionAdjustment, luv:AccumulatedOtherAdjustmentsAttributableToParent


Stockholders
Period End2020-12-31
Value-31.0
Percentage of StockholdersEquity-0.3
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment luv:AccumulatedOtherAdjustmentsAttributableToParent0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Stockholders
Period End2020-12-31
Value12
Percentage of StockholdersEquity0.1
Percentage of Assets0.0
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-31
Value-19.0
Percentage of StockholdersEquity-0.2
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccumulatedOtherComprehensiveIncome0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:RetainedEarnings


Stockholders
Period End2020-12-31
Value19
Percentage of StockholdersEquity0.2
Percentage of Assets0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquity us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Stockholders
Period End2021-06-302021-03-312020-12-31
Value27412-119.0
Percentage of StockholdersEquity2.80.1-1.3
Percentage of Assets0.70.0-0.3
Percentage of Assets us-gaap:CommodityContract us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.0

us-gaap:InterestRateContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Stockholders
Period End2021-06-302021-03-312020-12-31
Value-59.0-53.0-66.0
Percentage of StockholdersEquity-0.6-0.6-0.7
Percentage of Assets-0.2-0.1-0.2
Percentage of Assets us-gaap:InterestRateContract us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

luv:AccumulatedOtherAdjustmentsAttributableToParent


Stockholders
Period End2020-12-31
Value91
Percentage of StockholdersEquity1.0
Percentage of Assets0.3
Percentage of Assets luv:AccumulatedOtherAdjustmentsAttributableToParent0.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Stockholders
Period End2021-06-302021-03-312020-12-31
Value-36.02432
Percentage of StockholdersEquity-0.40.30.4
Percentage of Assets-0.10.10.1
Percentage of Assets us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss0.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value136-60.0-105.0-102.0-130.0-186.0-61.0-63.03096204122987812-323.0-1051.0-738.0-3.0-119.0-224.0-262.0-578.0-984.01241
Percentage of StockholdersEquity1.4-0.7-1.2-1.0-1.2-2.0-0.6-0.60.31.00.24.13.00.80.1-3.8-14.3-10.9-0.0-1.7-3.3-4.2-10.6-19.917.9
Percentage of Assets0.4-0.2-0.3-0.3-0.4-0.7-0.2-0.20.10.40.11.51.10.30.0-1.4-4.9-3.7-0.0-0.6-1.2-1.7-4.10.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value4269422041914175415915821581155415341513151014851469145214511410137413151231121012221183121612151207
Percentage of StockholdersEquity44.146.447.242.738.217.416.115.615.415.515.314.614.715.113.916.718.719.416.817.317.819.022.324.617.4
Percentage of Assets11.211.912.111.711.75.96.15.95.85.75.85.55.65.75.86.16.46.56.46.56.87.78.50.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value888888888888888808808808808808808808808808808808808808808808808808808808808
Percentage of StockholdersEquity9.29.810.09.18.28.98.28.18.18.38.28.08.18.47.79.611.011.911.011.611.713.014.816.411.7
Percentage of Assets2.32.52.62.52.53.03.13.13.13.13.13.03.13.23.23.53.84.04.24.34.55.25.70.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value15260149121477715685168421775717945175251696216320159671540214878142381462111418940974166431576853955399497149074776
Percentage of StockholdersEquity157.5164.0166.5160.6154.8195.7182.5176.5170.6166.7162.1151.7148.8148.0140.2135.3127.9109.587.782.578.486.691.199.368.9
Percentage of Assets39.942.042.744.147.366.069.366.264.361.760.857.356.255.858.249.044.136.733.231.029.934.934.80.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-10865.0-10867.0-10875.0-10877.0-10881.0-10886.0-10441.0-9893.0-9394.0-8946.0-8452.0-7954.0-7456.0-6957.0-6462.0-4872.0-3182.0-2026.0-1131.0-675.0-324.0-891.0-963.0-1005.0-1103.0
Percentage of StockholdersEquity-112.1-119.5-122.5-111.3-100.0-120.0-106.2-99.6-94.5-91.4-85.8-78.3-74.6-72.3-62.0-57.7-43.2-29.9-15.4-9.7-4.7-14.3-17.7-20.3-15.9
Percentage of Assets-28.4-30.6-31.4-30.5-30.6-40.5-40.3-37.4-35.6-33.8-32.2-29.6-28.2-27.3-25.7-20.9-14.9-10.0-5.8-3.6-1.8-5.8-6.70.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent

us-gaap:AssetsCurrent


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value191881610015173161331587270285974565055545483502856015408480148154280434346584498483944694574402445734596496344044985531748144456477348644514422746524691512043450.0045940.005421532942793358
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets50.245.443.945.344.626.123.121.321.120.719.220.820.418.819.217.718.219.619.321.019.920.618.921.621.823.521.824.325.524.123.024.625.123.522.724.725.327.224.025.728.632.527.723.5

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
Value14124119711106312109123513940254824882446234418542104211418221495146015371851168019662040238815831740177220251282183218821741135513331489133811131168108315588290.0010160.001595203912610.0010310.0009891110111413682213
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 Assets37.033.732.034.034.714.79.89.49.38.97.17.88.07.16.06.06.47.87.28.59.110.77.48.28.49.66.38.99.08.77.06.97.77.06.06.25.88.34.65.78.412.48.20.00.00.07.80.00.0

Short Term Investments

us-gaap:ShortTermInvestments

us-gaap:ShortTermInvestments


Short
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2751237722712453210616051524152815401517183517161572142117781580161516311625148013751194146813561360141317061728211217571797199519041797185720672173222623150.002640.002779242622771479
Percentage of ShortTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.26.76.66.95.96.05.95.85.85.77.06.45.95.67.16.56.86.97.06.46.15.46.96.46.56.78.48.410.18.89.310.39.89.410.011.011.711.812.814.814.714.814.710.4

Accounts Receivable Net Current

us-gaap:AccountsReceivableNetCurrent

us-gaap:AccountsReceivableNetCurrent


Accounts
Period End2021-06-302020-12-31
Value8146
Percentage of AccountsReceivableNetCurrent100.0100.0
Percentage of Assets0.20.1

Prepaid Expense And Other Assets Current

us-gaap:PrepaidExpenseAndOtherAssetsCurrent

us-gaap:PrepaidExpenseAndOtherAssetsCurrent


Prepaid
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value5213672952482232562872392813543105144984484602232502353102142021921882392552702322912762412502282092152102242033182380.000110.00026426289
Percentage of PrepaidExpenseAndOtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.00.90.70.61.01.10.91.11.31.21.91.91.81.80.91.01.01.30.90.90.90.91.11.21.31.11.41.31.21.31.21.11.11.11.21.11.71.30.61.41.60.6

Property Plant And Equipment Gross

us-gaap:PropertyPlantAndEquipmentGross

us-gaap:PropertyPlantAndEquipmentGross


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2744127381275742749927411279012771328287278972764829256287162823228169282292780127202267832646425841256582523124685238252352323062225132205621587210632082020438202231999119497192941894218551184210.0179830.017767164151634315888
Percentage of PropertyPlantAndEquipmentGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets71.877.179.777.277.0103.8107.0106.9105.8104.5111.5106.8106.7110.5112.4114.6113.7112.7113.6112.1114.3113.4115.8112.6111.6109.0111.5107.4103.3105.4107.6105.5104.3104.1104.8102.6102.398.5102.0100.593.8100.0105.7111.3

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
Value1219911733117431144311164109121068810445101649875973194379166939696909645952394979420929593649267908488968663845582218091786076437431723570596861673167226600645662940.0061490.006046591957655254
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 Assets31.933.134.032.131.440.641.339.538.537.337.135.134.636.838.639.839.840.040.540.341.741.742.642.041.140.040.739.437.638.338.437.436.435.736.235.735.634.334.834.431.936.137.336.8

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


Property
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1524215648158311605616247169891702517842177331777319525192791906618773185391815617679172861704416546162941596415601149291486014607142921396513727134201338913203131641313012766125721234212095121270.0118340.011721104961057810634
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets39.944.145.845.145.663.265.767.467.267.274.471.772.073.673.874.973.972.773.271.872.671.873.270.670.569.070.868.065.767.269.268.267.968.468.666.866.764.267.166.261.963.968.474.5

Goodwill

us-gaap:Goodwill

us-gaap:Goodwill


Goodwill
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value9709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709709700.000970.0009710.0
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets2.52.72.82.72.73.63.73.73.73.73.73.63.73.83.94.04.14.14.24.24.34.44.64.64.64.64.84.74.64.95.05.05.05.15.25.25.25.25.45.45.10.0

Intangible Assets Net Excluding Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill


Intangible
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-31
Value295295295295295296296311312313400403406410413416419423426430434460464469474479363366369372166
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.80.80.90.80.81.11.11.21.21.21.51.51.51.61.61.71.81.81.81.91.92.12.22.22.22.31.81.81.81.90.9

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
Value19692032189217671845127813491352142415080.0
Percentage of OperatingLeaseRightOfUseAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets5.25.75.55.05.24.85.25.15.45.70.0

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
Value837743722679662620577653693725720103210219597868439298497746907147337176876496235346198777725304183845836336195136416260.0004870.000832589606277
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 Assets2.22.12.11.91.92.32.22.52.62.72.73.83.93.83.13.53.93.63.33.03.23.33.43.23.12.92.63.04.23.92.72.22.03.03.43.32.83.43.52.74.43.63.91.9

Other Assets

us-gaap:OtherAssets

us-gaap:OtherAssets


Other
Period End2020-12-312020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value722662620577653693725720103210219597868439298497746907147337176876496235346198777725304183845836336195136416260.0004870.0008320.000606
Percentage of OtherAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets2.11.92.32.22.52.62.72.73.83.93.83.13.53.93.63.33.03.23.33.43.23.12.92.63.04.23.92.72.22.03.03.43.32.83.43.52.74.40.0

Accounts Payable Current

us-gaap:AccountsPayableCurrent

us-gaap:AccountsPayableCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value1378109493198097010431574127413301412141612241338124313201124121712141178102112471153118812351134114512031185129212991247113412321250110711401153120810570.0010830.0010490.000739
Percentage of AccountsPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.63.12.72.82.73.96.14.85.05.35.44.65.14.95.34.65.15.15.14.45.65.25.65.85.45.46.05.86.26.56.45.96.46.56.06.16.26.45.96.15.50.0

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
Value235316652259183623721037174914561315135017491517136111341777159315611947198521461869247225912049165118741565127716451168122911721207100411021040114210249960.0011930.00113827863729
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 Assets6.24.76.55.26.73.96.85.55.05.16.75.65.14.47.16.66.58.28.59.38.311.112.29.77.88.97.76.27.95.86.46.16.25.25.95.56.25.45.56.76.05.05.65.1

Contract With Customer Liability Current

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:ContractWithCustomerLiabilityCurrent


Contract
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value6312490637903952498850364457
Percentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets16.513.811.011.114.018.717.2

Liabilities Current

us-gaap:LiabilitiesCurrent

us-gaap:LiabilitiesCurrent


Liabilities
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value124768182750678049361102418952862986118723790578437716716269056965709774586844781678338253740670846876690359236446702764415676554657795411465049695080504745330.005320.005318435833052695
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets32.723.121.721.926.338.134.632.632.633.030.129.229.228.127.528.729.731.429.433.934.937.134.833.532.632.629.331.433.632.229.328.629.828.225.026.427.426.825.129.728.126.621.418.9

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
Value2672923063163363303533323503610.0
Percentage of OperatingLeaseLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets0.70.80.90.90.91.21.41.31.31.40.0

us-gaap:OperatingLeaseLiabilityCurrent us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:PropertySubjectToOperatingLease


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-31
Value306353332350361
Percentage of OperatingLeaseLiabilityCurrent100.0100.0100.0100.0100.0
Percentage of Assets0.91.41.31.31.4
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.00.00.00.00.0

Other Accrued Liabilities Current

us-gaap:OtherAccruedLiabilitiesCurrent

us-gaap:OtherAccruedLiabilitiesCurrent


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
Value2921222573272331802552492603833883322001583462282052022372192102052462192581922362552332172232032021982121922272112780.0002950.000302225211187
Percentage of OtherAccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.80.30.70.90.70.71.00.91.01.41.51.20.80.61.40.90.90.91.01.00.90.91.21.01.20.91.21.21.11.11.21.01.01.01.11.01.21.11.51.61.61.41.41.3

Taxes Payable Current

us-gaap:TaxesPayableCurrent

us-gaap:TaxesPayableCurrent


Taxes
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value26619049413866227188269291220196277282203180266280184165239246179157234229163142214218146128
Percentage of TaxesPayableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.70.50.10.10.10.20.90.71.01.10.80.71.01.10.80.71.11.20.80.71.11.10.80.71.11.10.80.71.01.10.80.7

Long Term Debt

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

us-gaap:LongTermDebt

luv:A10PayrollSupportProgramLoanDue2030, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value976
Percentage of LongTermDebt100.0
Percentage of Assets2.6
Percentage of Assets luv:A10PayrollSupportProgramLoanDue2030 us-gaap:UnsecuredDebt0.0

luv:A10PayrollSupportProgramLoanDue2031, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value566
Percentage of LongTermDebt58.0
Percentage of Assets1.5
Percentage of Assets luv:A10PayrollSupportProgramLoanDue2031 us-gaap:UnsecuredDebt0.0

luv:A10PayrollSupportProgramLoanDueApril2031, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value526
Percentage of LongTermDebt53.9
Percentage of Assets1.4
Percentage of Assets luv:A10PayrollSupportProgramLoanDueApril2031 us-gaap:UnsecuredDebt0.0

luv:A1250ConvertibleSeniorNotesDue2025, us-gaap:ConvertibleDebt


Long
Period End2021-06-302021-03-312020-12-31
Value198219631945
Percentage of LongTermDebt203.10.00.0
Percentage of Assets5.25.55.6
Percentage of Assets luv:A1250ConvertibleSeniorNotesDue2025 us-gaap:ConvertibleDebt0.00.00.0

luv:A160TermLoanAgreementPayableThrough2028, us-gaap:NotesPayableToBanks


Long
Period End2021-06-30
Value171
Percentage of LongTermDebt17.5
Percentage of Assets0.4
Percentage of Assets luv:A160TermLoanAgreementPayableThrough2028 us-gaap:NotesPayableToBanks0.0

luv:A345UnsecuredSeniorNotesDue2027, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value300
Percentage of LongTermDebt30.7
Percentage of Assets0.8
Percentage of Assets luv:A345UnsecuredSeniorNotesDue2027 us-gaap:UnsecuredDebt0.0

luv:A4750UnsecuredNotesDue2023, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value1250
Percentage of LongTermDebt128.1
Percentage of Assets3.3
Percentage of Assets luv:A4750UnsecuredNotesDue2023 us-gaap:UnsecuredDebt0.0

luv:A5125NotesDue2027, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value2000
Percentage of LongTermDebt204.9
Percentage of Assets5.2
Percentage of Assets luv:A5125NotesDue2027 us-gaap:UnsecuredDebt0.0

luv:A5250UnsecuredNotesDue2025, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value1550
Percentage of LongTermDebt158.8
Percentage of Assets4.1
Percentage of Assets luv:A5250UnsecuredNotesDue2025 us-gaap:UnsecuredDebt0.0

luv:DebenturesDue2027, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value118
Percentage of LongTermDebt12.1
Percentage of Assets0.3
Percentage of Assets luv:DebenturesDue2027 us-gaap:UnsecuredDebt0.0

luv:TermLoanAgreementDue2025, us-gaap:NotesPayableToBanks


Long
Period End2021-06-30
Value106
Percentage of LongTermDebt10.9
Percentage of Assets0.3
Percentage of Assets luv:TermLoanAgreementDue2025 us-gaap:NotesPayableToBanks0.0

luv:TermLoanAgreementDue2026, us-gaap:NotesPayableToBanks


Long
Period End2021-06-30
Value149
Percentage of LongTermDebt15.3
Percentage of Assets0.4
Percentage of Assets luv:TermLoanAgreementDue2026 us-gaap:NotesPayableToBanks0.0

luv:TotalPassThroughCertificates, us-gaap:EnhancedEquipmentTrustCertificate


Long
Period End2021-06-30
Value105
Percentage of LongTermDebt10.8
Percentage of Assets0.3
Percentage of Assets luv:TotalPassThroughCertificates us-gaap:EnhancedEquipmentTrustCertificate0.0

luv:UnsecuredSeniorNotesDue2022, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value300
Percentage of LongTermDebt30.7
Percentage of Assets0.8
Percentage of Assets luv:UnsecuredSeniorNotesDue2022 us-gaap:UnsecuredDebt0.0

luv:UnsecuredSeniorNotesDue2026, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value300
Percentage of LongTermDebt30.7
Percentage of Assets0.8
Percentage of Assets luv:UnsecuredSeniorNotesDue2026 us-gaap:UnsecuredDebt0.0

luv:UnsecuredSeniorNotesDue2030, us-gaap:UnsecuredDebt


Long
Period End2021-06-30
Value500
Percentage of LongTermDebt51.2
Percentage of Assets1.3
Percentage of Assets luv:UnsecuredSeniorNotesDue2030 us-gaap:UnsecuredDebt0.0

Debt And Capital Lease Obligations

us-gaap:DebtAndCapitalLeaseObligations

us-gaap:DebtAndCapitalLeaseObligations


Debt
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value1038126783396369334103198271328423175
Percentage of DebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets30.010.312.914.714.615.013.414.717.1

Long Term Debt And Capital Lease Obligations

us-gaap:LongTermDebtAndCapitalLeaseObligations

us-gaap:LongTermDebtAndCapitalLeaseObligations


Long
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value91881054610111101358905228818462398244926022771310031553227332027632788278128212323239123552541238124112416243421252153217221912883
Percentage of LongTermDebtAndCapitalLeaseObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets24.029.729.228.525.08.57.19.19.39.810.611.511.912.713.211.411.711.712.110.110.710.611.911.311.411.412.010.310.310.911.315.5

Deferred Income Tax Liabilities Net

us-gaap:DeferredIncomeTaxLiabilitiesNet

us-gaap:DeferredIncomeTaxLiabilitiesNet


Deferred
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value1688166016341824211422782364
Percentage of DeferredIncomeTaxLiabilitiesNet100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.44.74.75.15.98.59.1

Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent

us-gaap:PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent


Pension
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302010-12-31
Value4324304283392992942882452402352322942882822752742672612562152112062011791761721691431441401381691621541481161121091070.0001059.8e-059.1e-05
Percentage of PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.11.21.21.00.81.11.10.90.90.90.91.11.11.11.11.11.11.11.10.90.90.90.90.80.80.80.80.70.70.70.70.90.80.80.80.60.60.60.60.60.50.0

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
Value112011231247123372269470664463960865074869270670771370870372866168170376093170810951255658710726771119812111153112411149459249100.0009260.000838460465493
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 Assets2.93.23.63.52.02.62.72.42.42.32.52.82.62.82.82.93.03.03.12.93.03.23.64.43.45.26.23.23.43.64.06.26.26.06.05.95.14.95.05.24.42.83.03.5

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
Value167917221562142414869369781014107211500.0
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets4.44.94.54.04.23.53.83.84.14.30.0

us-gaap:OperatingLeaseLiabilityNoncurrent us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:PropertySubjectToOperatingLease


Operating
Period End2020-12-312019-12-312019-09-302019-06-302019-03-31
Value1562978101410721150
Percentage of OperatingLeaseLiabilityNoncurrent100.0100.0100.0100.0100.0
Percentage of Assets4.53.83.84.14.3
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.00.00.00.00.0

Lessee Operating Lease Liability Payments Due Year Two

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value253
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearTwo100.0
Percentage of Assets0.7
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Payments Due Year Three

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearThree

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value219
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearThree100.0
Percentage of Assets0.6
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Payments Due Year Four

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFour

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value193
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFour100.0
Percentage of Assets0.6
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Payments Due Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueYearFive

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value156
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueYearFive100.0
Percentage of Assets0.5
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Payments Due After Year Five

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value1156
Percentage of LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive100.0
Percentage of Assets3.3
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Operating Lease Liability

us-gaap:OperatingLeaseLiability us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:OperatingLeaseLiability

us-gaap:PropertySubjectToOperatingLease


Operating
Period End2020-12-31
Value1868
Percentage of OperatingLeaseLiability100.0
Percentage of Assets5.4
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Payments Due

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityPaymentsDue

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value2348
Percentage of LesseeOperatingLeaseLiabilityPaymentsDue100.0
Percentage of Assets6.8
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Lessee Operating Lease Liability Undiscounted Excess Amount

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount us-gaap:PropertySubjectToOrAvailableForOperatingLease

us-gaap:LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

us-gaap:PropertySubjectToOperatingLease


Lessee
Period End2020-12-31
Value480
Percentage of LesseeOperatingLeaseLiabilityUndiscountedExcessAmount100.0
Percentage of Assets1.4
Percentage of Assets us-gaap:PropertySubjectToOperatingLease0.0

Stockholders Equity

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value9688909388769769108789075983299319940979198531015399979619104308800853082048441804778217496735869687158690267757429751671907336701367816961699270026840709768770.0064850.00720265876237545449416929
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets25.425.625.727.430.633.838.037.537.737.037.537.837.837.741.536.335.734.536.234.934.833.734.532.934.032.633.536.236.036.037.936.235.036.337.637.236.937.738.136.338.040.140.338.20.00.0

us-gaap:StockholdersEquity us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:AdjustmentsForNewAccountingPronouncements, us-gaap:StatementEquityComponents

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccountingStandardsUpdate201601, us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-31
Value-19.0
Percentage of StockholdersEquity-0.2
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccountingStandardsUpdate201601 us-gaap:AccumulatedOtherComprehensiveIncome0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccountingStandardsUpdate201601, us-gaap:RetainedEarnings


Stockholders
Period End2020-12-31
Value19
Percentage of StockholdersEquity0.2
Percentage of Assets0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccountingStandardsUpdate201601 us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquity us-gaap:CumulativeEffectPeriodOfAdoption, us-gaap:StatementEquityComponents

srt:CumulativeEffectPeriodOfAdoptionAdjustment, luv:AccumulatedOtherAdjustmentsAttributableToParent


Stockholders
Period End2020-12-31
Value-31.0
Percentage of StockholdersEquity-0.3
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment luv:AccumulatedOtherAdjustmentsAttributableToParent0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Stockholders
Period End2020-12-31
Value12
Percentage of StockholdersEquity0.1
Percentage of Assets0.0
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2020-12-31
Value-19.0
Percentage of StockholdersEquity-0.2
Percentage of Assets-0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:AccumulatedOtherComprehensiveIncome0.0

srt:CumulativeEffectPeriodOfAdoptionAdjustment, us-gaap:RetainedEarnings


Stockholders
Period End2020-12-31
Value19
Percentage of StockholdersEquity0.2
Percentage of Assets0.1
Percentage of Assets srt:CumulativeEffectPeriodOfAdoptionAdjustment us-gaap:RetainedEarnings0.0

us-gaap:StockholdersEquity us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Stockholders
Period End2021-06-302021-03-312020-12-31
Value27412-119.0
Percentage of StockholdersEquity2.80.1-1.3
Percentage of Assets0.70.0-0.3
Percentage of Assets us-gaap:CommodityContract us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.0

us-gaap:InterestRateContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Stockholders
Period End2021-06-302021-03-312020-12-31
Value-59.0-53.0-66.0
Percentage of StockholdersEquity-0.6-0.6-0.7
Percentage of Assets-0.2-0.1-0.2
Percentage of Assets us-gaap:InterestRateContract us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

luv:AccumulatedOtherAdjustmentsAttributableToParent


Stockholders
Period End2020-12-31
Value91
Percentage of StockholdersEquity1.0
Percentage of Assets0.3
Percentage of Assets luv:AccumulatedOtherAdjustmentsAttributableToParent0.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Stockholders
Period End2021-06-302021-03-312020-12-31
Value-36.02432
Percentage of StockholdersEquity-0.40.30.4
Percentage of Assets-0.10.10.1
Percentage of Assets us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss0.00.00.0

us-gaap:AccumulatedOtherComprehensiveIncome


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value136-60.0-105.0-102.0-130.0-186.0-61.0-63.03096204122987812-323.0-1051.0-738.0-3.0-119.0-224.0-262.0-578.0-984.01241
Percentage of StockholdersEquity1.4-0.7-1.2-1.0-1.2-2.0-0.6-0.60.31.00.24.13.00.80.1-3.8-14.3-10.9-0.0-1.7-3.3-4.2-10.6-19.917.9
Percentage of Assets0.4-0.2-0.3-0.3-0.4-0.7-0.2-0.20.10.40.11.51.10.30.0-1.4-4.9-3.7-0.0-0.6-1.2-1.7-4.10.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value4269422041914175415915821581155415341513151014851469145214511410137413151231121012221183121612151207
Percentage of StockholdersEquity44.146.447.242.738.217.416.115.615.415.515.314.614.715.113.916.718.719.416.817.317.819.022.324.617.4
Percentage of Assets11.211.912.111.711.75.96.15.95.85.75.85.55.65.75.86.16.46.56.46.56.87.78.50.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value888888888888888808808808808808808808808808808808808808808808808808808808808
Percentage of StockholdersEquity9.29.810.09.18.28.98.28.18.18.38.28.08.18.47.79.611.011.911.011.611.713.014.816.411.7
Percentage of Assets2.32.52.62.52.53.03.13.13.13.13.13.03.13.23.23.53.84.04.24.34.55.25.70.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value15260149121477715685168421775717945175251696216320159671540214878142381462111418940974166431576853955399497149074776
Percentage of StockholdersEquity157.5164.0166.5160.6154.8195.7182.5176.5170.6166.7162.1151.7148.8148.0140.2135.3127.9109.587.782.578.486.691.199.368.9
Percentage of Assets39.942.042.744.147.366.069.366.264.361.760.857.356.255.858.249.044.136.733.231.029.934.934.80.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock


Stockholders
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-10865.0-10867.0-10875.0-10877.0-10881.0-10886.0-10441.0-9893.0-9394.0-8946.0-8452.0-7954.0-7456.0-6957.0-6462.0-4872.0-3182.0-2026.0-1131.0-675.0-324.0-891.0-963.0-1005.0-1103.0
Percentage of StockholdersEquity-112.1-119.5-122.5-111.3-100.0-120.0-106.2-99.6-94.5-91.4-85.8-78.3-74.6-72.3-62.0-57.7-43.2-29.9-15.4-9.7-4.7-14.3-17.7-20.3-15.9
Percentage of Assets-28.4-30.6-31.4-30.5-30.6-40.5-40.3-37.4-35.6-33.8-32.2-29.6-28.2-27.3-25.7-20.9-14.9-10.0-5.8-3.6-1.8-5.8-6.70.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap:StatementEquityComponents

us-gaap:StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

luv:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesInterestRateDerivative


Stockholders
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value-53.0-66.0-71.0-74.0-75.0-33.0-53.0-33.0-14.00.0-1.0-2.0-4.0-7.0-11.0-13.0-15.0-18.0-26.0-32.0-30.0-45.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets-0.1-0.2-0.2-0.2-0.3-0.1-0.2-0.1-0.10.0-0.0-0.0-0.0-0.0-0.0-0.1-0.1-0.1-0.1-0.1-0.1-0.2
Percentage of Assets luv:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesInterestRateDerivative0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

luv:OtherComprehensiveIncomeOtherChangesNetOfTax


Stockholders
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-312013-12-31
Value9169552259474539254336333326222020116.06.06.03.08.08.08.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-137.9-97.2-74.3-29.3-178.8-88.7-136.4-278.60.0-4300.0-1800.0-825.0-471.4-236.4-169.2-133.3-111.1-42.3-18.80.0-20.00.00.0-17.80.0
Percentage of Assets0.30.20.20.10.20.20.20.10.10.20.10.10.10.10.10.10.10.00.00.00.00.00.00.00.0
Percentage of Assets luv:OtherComprehensiveIncomeOtherChangesNetOfTax0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedDefinedBenefitPlansAdjustment


Stockholders
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value-43.0-43.02020202058585858-9.0-9.0-9.0-9.0-14.0-14.0-14.0-14.0222222224165
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest81.165.2-28.2-27.0-26.7-60.6-109.4-175.8-414.30.0900.0450.0225.0128.6127.3107.793.377.8-84.6-68.80.0-73.3-91.10.0
Percentage of Assets-0.1-0.10.10.10.10.10.20.20.20.2-0.0-0.0-0.0-0.0-0.1-0.1-0.1-0.10.10.10.10.10.20.3
Percentage of Assets us-gaap:AccumulatedDefinedBenefitPlansAdjustment0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Stockholders
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value12-119.0-151.0-170.0-209.0-125.0-135.0-31.042-56.0504365833.0-216.0-412.0-485.0-499.0-799.0-993.0-1666.0-1177.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-22.6180.3212.7229.7278.7378.8254.793.9-300.00.0-50400.0-18250.0-2075.0-42.91963.63169.23233.32772.23073.13103.15553.32615.6
Percentage of Assets0.0-0.3-0.4-0.5-0.8-0.5-0.5-0.10.2-0.21.91.40.30.0-0.9-1.7-2.0-2.1-3.5-4.4-7.8-5.8
Percentage of Assets us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Stockholders
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value24323139561820-9.0-29.0-7.0-125.0-92.0-25.0-8.079154182188293369617435
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest-45.3-48.5-43.7-52.7-74.7-54.5-37.727.3207.10.012500.04600.0625.0114.3-718.2-1184.6-1213.3-1044.4-1126.9-1153.1-2056.7-966.7
Percentage of Assets0.10.10.10.10.20.10.1-0.0-0.1-0.0-0.5-0.3-0.1-0.00.30.60.80.81.31.62.92.2
Percentage of Assets us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest


Stockholders
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302014-12-312013-12-31
Value-60.0-105.0-102.0-130.0-186.0-61.0-63.03096204122987812-136.0-263.0-312.0-323.0-499.0-628.0-894.0-1051.0-903.0-664.0-738.0-3.0
Percentage of StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest113.2159.1143.7175.7248.0184.8118.9-90.9-685.70.0-41200.0-14900.0-1950.0-171.41236.42023.12080.01794.41919.21962.50.03503.30.00.01640.00.0
Percentage of Assets-0.2-0.3-0.3-0.4-0.7-0.2-0.20.10.40.11.51.10.30.0-0.6-1.1-1.3-1.4-2.2-2.8-4.0-4.9-4.3-3.2-3.7-0.0
Percentage of Assets us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

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
Value8888888888888888088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088088080.0008080.000808808808808
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 Assets2.32.52.62.52.53.03.13.13.13.13.13.03.13.23.23.33.43.43.53.53.63.63.83.83.83.84.03.93.94.04.24.24.24.24.34.34.44.34.54.54.34.95.25.7

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
Value4269422041914175415915821581155415341513151014851469145214511436142214191410140213831387137413301319132913151280126312561231120512011214121012281224122512220.0012220.001219118611831216
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 Assets11.211.912.111.711.75.96.15.95.85.75.85.55.65.75.85.95.96.06.16.16.26.26.46.36.36.36.56.26.06.36.46.26.26.36.56.56.66.56.86.86.47.27.78.5

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
Value1526014912147771568516842177571794517525169621632015967154021487814238146211280612378117081141810957106319872940989228387782974167266697965556431624660155818576857005692548653950.0052510.005398539953994971
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 Assets39.942.042.744.147.366.069.366.264.361.760.857.356.255.858.252.851.749.349.047.547.444.444.142.239.837.036.735.433.432.833.232.331.030.331.030.330.729.129.929.428.532.934.934.8

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


Accumulated
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-31
Value136-60.0-105.0-102.0-130.0-186.0-61.0-63.03096204122987812-136.0-263.0-312.0-323.0-499.0-628.0-894.0-1051.0-903.0-664.0-742.0-738.0-92.0111-12.0-3.0-114.0-248.0-111.0-119.0-125.0-320.0-57.0-224.0-0.000513-0.00010779-262.0-578.0-984.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.4-0.2-0.3-0.3-0.4-0.7-0.2-0.20.10.40.11.51.10.30.0-0.6-1.1-1.3-1.4-2.2-2.8-4.0-4.9-4.3-3.2-3.5-3.7-0.40.5-0.1-0.0-0.6-1.3-0.6-0.6-0.7-1.7-0.3-1.2-2.9-0.60.5-1.7-4.10.0

Treasury Stock Value

us-gaap:TreasuryStockValue

us-gaap:TreasuryStockValue


Treasury
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1086510867108751087710881108861044198939394894684527954745669576462611458155419487246214373367731823189269223222026183316451417113111329957686756095643653240.0002830.000116-885.0-891.0-963.0
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets28.430.631.430.530.640.540.337.435.633.832.229.628.227.325.725.224.322.820.920.119.516.514.915.112.811.010.08.97.97.15.85.85.14.03.63.23.01.91.81.60.6-5.4-5.8-6.7

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

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue


Adjustments
Period End2021-06-302021-03-312020-06-302020-03-31
Value1614-2.09.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0
Percentage of Assets0.00.00.00.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-06-302020-03-31
Value1614-2.09.0
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0
Percentage of Assets0.00.00.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.0

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
Value2005645-596.0-1050.0897-377.08241091966110598912711631100256399674616257098561112161632483662714522042401338111928942877898323146414512251384-0.0002180.00023796515600.0003850.00054373
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 RevenueFromContractWithCustomerExcludingAssessedTax50.031.4-29.6-58.689.0-8.914.419.316.321.517.322.828.420.310.718.813.033.314.016.720.733.56.515.712.332.94.45.026.726.96.59.416.824.15.510.83.130.733.7-5.15.731.150.10.00.014.2

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-469.0-201.091-434.0332-5.0144-359.0-252.0164-668.0-604.0-694.0-73.0-735.0-620.0-584.0-470.0-839.0-584.0-674.0-175.0-946.0-259.0-407.0-302.0-468.0-44.0-857.0-358.0-254.0-359.0-300.0-472.0-189.0-277.0-355.0-12.0-1050.999043-0.000137-0.000589-231.0-1264.998755-0.000312-0.00061-322.0
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 RevenueFromContractWithCustomerExcludingAssessedTax-11.7-9.84.5-24.232.9-0.12.5-6.4-4.33.2-11.7-10.8-12.1-1.5-13.9-11.7-10.2-9.6-16.5-11.4-12.5-3.6-19.0-4.9-8.0-6.8-10.1-0.9-17.1-8.6-5.7-7.9-6.5-11.6-4.5-6.4-7.7-0.3-25.6-3.2-14.2-7.4-40.6-0.0-0.0-12.2

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
Value617464-541.0124271821774-908.0-690.0-612.0-779.0-571.0-677.0-645.0-602.0207-453.0-476.0-984.0-156.0-346.0-786.0-636.0465-609.0-473.0-407.0-286.0-246.0-340.0-375.0-13.0-225.0-327.0-286.0-97.0-102.0-265.0-484.0-765.999727-0.000224-9.2e-0544-148.99987-3.1e-05-5.1e-05-55.0
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 RevenueFromContractWithCustomerExcludingAssessedTax15.422.6-26.969.3712.541.9-15.8-12.2-10.4-15.1-10.0-12.1-11.2-12.23.9-8.5-8.3-20.2-3.1-6.7-14.6-13.29.3-11.5-9.3-9.2-6.2-5.1-6.8-9.0-0.3-5.0-7.0-7.0-2.3-2.4-5.7-12.1-18.6-5.2-2.21.4-4.8-0.0-0.0-2.1

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

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


Cash
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2153908-1046.0-242.0841113926042102490
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax53.744.2-52.0-13.5834.432.91.00.71.79.5

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
Value2005645-596.0-1050.0897-377.08241091966110598912711631100256399674616257098561112161632483662714522042401338111928942877898323146414512251384-0.0002180.00023796515600.0003850.00054373
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 RevenueFromContractWithCustomerExcludingAssessedTax50.031.4-29.6-58.689.0-8.914.419.316.321.517.322.828.420.310.718.813.033.314.016.720.733.56.515.712.332.94.45.026.726.96.59.416.824.15.510.83.130.733.7-5.15.731.150.10.00.014.2

Net Income Loss

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


Net
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value348116-908.0-1157.0-915.0-94.0514659741387654615733463188850374635152238882051153658460845319032946515221225922459781622898152-0.000140.0001615.013120511211116-16.091-91.0
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax8.75.7-45.1-64.5-90.8-2.29.011.712.57.511.511.012.89.435.89.513.07.210.37.615.210.610.811.011.910.34.16.99.33.64.85.74.81.41.90.44.92.53.7-3.23.90.24.26.43.50.44.3-0.63.5-3.9

us-gaap:NetIncomeLoss us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Net
Period End2021-06-30
Value9.0
Percentage of NetIncomeLoss2.6
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:CommodityContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.0

us-gaap:InterestRateContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Net
Period End2021-06-30
Value1.0
Percentage of NetIncomeLoss0.3
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.0
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:InterestRateContract us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges0.0

us-gaap:NetIncomeLoss us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Net
Period End2021-06-30
Value10.0
Percentage of NetIncomeLoss2.9
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax0.2
Percentage of RevenueFromContractWithCustomerExcludingAssessedTax us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome0.0

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-469.0-201.091-434.0332-5.0144-359.0-252.0164-668.0-604.0-694.0-73.0-735.0-620.0-584.0-470.0-839.0-584.0-674.0-175.0-946.0-259.0-407.0-302.0-468.0-44.0-857.0-358.0-254.0-359.0-300.0-472.0-189.0-277.0-355.0-12.0-1050.999043-0.000137-0.000589-231.0-1264.998755-0.000312-0.00061-322.0
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 RevenueFromContractWithCustomerExcludingAssessedTax-11.7-9.84.5-24.232.9-0.12.5-6.4-4.33.2-11.7-10.8-12.1-1.5-13.9-11.7-10.2-9.6-16.5-11.4-12.5-3.6-19.0-4.9-8.0-6.8-10.1-0.9-17.1-8.6-5.7-7.9-6.5-11.6-4.5-6.4-7.7-0.3-25.6-3.2-14.2-7.4-40.6-0.0-0.0-12.2

Payments To Acquire Productive Assets

us-gaap:PaymentsToAcquireProductiveAssets

us-gaap:PaymentsToAcquireProductiveAssets


Payments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value95959089113224261375230160538454521409520638551414674464462438810230428573408433500407438268193534
Percentage of PaymentsToAcquireProductiveAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value617464-541.0124271821774-908.0-690.0-612.0-779.0-571.0-677.0-645.0-602.0207-453.0-476.0-984.0-156.0-346.0-786.0-636.0465-609.0-473.0-407.0-286.0-246.0-340.0-375.0-13.0-225.0-327.0-286.0-97.0-102.0-265.0-484.0-765.999727-0.000224-9.2e-0544-148.99987-3.1e-05-5.1e-05-55.0
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 RevenueFromContractWithCustomerExcludingAssessedTax15.422.6-26.969.3712.541.9-15.8-12.2-10.4-15.1-10.0-12.1-11.2-12.23.9-8.5-8.3-20.2-3.1-6.7-14.6-13.29.3-11.5-9.3-9.2-6.2-5.1-6.8-9.0-0.3-5.0-7.0-7.0-2.3-2.4-5.7-12.1-18.6-5.2-2.21.4-4.8-0.0-0.0-2.1

Payments Of Dividends

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends


Payments
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value0.00.00.01880.096981780.091931480.075761230.0626396495081133e-063e-06-7.0-13.0000133e-063e-06-7.0
Percentage of PaymentsOfDividends0.00.00.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock

us-gaap:PaymentsForRepurchaseOfCommonStock


Payments
Period 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
Value0.00.00.04515505004505005005005005003503004005503002507005000.0500380300200200240315391502511007550225502240.0001750.00.00.00.00.0
Percentage of PaymentsForRepurchaseOfCommonStock0.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.00.0

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription, us-gaap:Range, us-gaap:VariableRate

us-gaap:DebtInstrumentInterestRateStatedPercentage

luv:Amended364DayTermLoanCreditFacility, srt:Minimum, us-gaap:BaseRate


Debt
Period End2020-12-312020-09-302020-06-302020-03-31
Value1.01.00.010.01
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:Amended364DayTermLoanCreditFacility srt:Minimum us-gaap:BaseRate0.00.00.00.0

luv:Amended364DayTermLoanCreditFacility, srt:Minimum, us-gaap:LondonInterbankOfferedRateLIBOR


Debt
Period End2020-12-312020-09-302020-06-302020-03-31
Value1.01.00.010.01
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:Amended364DayTermLoanCreditFacility srt:Minimum us-gaap:LondonInterbankOfferedRateLIBOR0.00.00.00.0

us-gaap:DebtInstrumentInterestRateStatedPercentage luv:DebtDescription, us-gaap:VariableRate

luv:Amended364DayTermLoanCreditFacility, luv:NewYorkFedBankRate


Debt
Period End2020-12-312020-09-302020-06-302020-03-31
Value0.50.50.0050.005
Percentage of DebtInstrumentInterestRateStatedPercentage50.050.050.050.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:Amended364DayTermLoanCreditFacility luv:NewYorkFedBankRate0.00.00.00.0

luv:Amended364DayTermLoanCreditFacility, us-gaap:LondonInterbankOfferedRateLIBOR


Debt
Period End2020-12-312020-09-302020-06-302020-03-31
Value1.01.00.010.01
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:Amended364DayTermLoanCreditFacility us-gaap:LondonInterbankOfferedRateLIBOR0.00.00.00.0

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument

luv:TermLoanAgreementDue2026


Debt
Period End2020-12-312019-12-312018-12-312017-12-312016-10-31
Value1.340.03030.03880.02670.0236
Percentage of DebtInstrumentInterestRateStatedPercentage134.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:TermLoanAgreementDue20260.00.00.00.00.0

us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument, us-gaap:LongtermDebtType

luv:CARESActUnsecuredLoan, us-gaap:UnsecuredDebt


Debt
Period End2020-12-312020-09-302020-06-30
Value1.01.00.01
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:CARESActUnsecuredLoan us-gaap:UnsecuredDebt0.00.00.0

luv:PayrollSupportProgramExtensionUnsecuredLoan, us-gaap:UnsecuredDebt


Debt
Period End2021-03-31
Value1.0
Percentage of DebtInstrumentInterestRateStatedPercentage0.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations luv:PayrollSupportProgramExtensionUnsecuredLoan us-gaap:UnsecuredDebt0.0

Deferred Tax Liabilities

us-gaap:DeferredTaxLiabilities

us-gaap:DeferredTaxLiabilities


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value163423642427235833742490432841893915362131322933
Percentage of DeferredTaxLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Proceeds From Sale Of Short Term Investments

us-gaap:ProceedsFromSaleOfShortTermInvestments

us-gaap:ProceedsFromSaleOfShortTermInvestments


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value127712181380119181894879854552857567753157456052556657355659254959153049150961478780477568073653130.0016640.00144131048510.0009390.0013491197
Percentage of ProceedsFromSaleOfShortTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityCurrentPeriodSales

luv:AirTrafficLiabilityCurrentPeriodSales


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value23241717168513814565488652325474570448265273552454034450484354385415
Percentage of AirTrafficLiabilityCurrentPeriodSales100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityRevenueamountsinbeginningbalance

luv:AirTrafficLiabilityRevenueamountsinbeginningbalance


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-743000000.0-191000000.0-190000000.013000000.0-1949000000.0-656000000.0-305000000.0-847000000.0-2008000000.0-381000000.0-485000000.0-786000000.0-1827000000.0-319000000.0-410000000.0-669000000.0-1701000000.0
Percentage of AirTrafficLiabilityRevenueamountsinbeginningbalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityRevenuefromCurrentPeriodSales

luv:AirTrafficLiabilityRevenuefromCurrentPeriodSales


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-982000000.0-1487000000.0-1280000000.0-726000000.0-1915000000.0-4686000000.0-4945000000.0-4657000000.0-2752000000.0-4958000000.0-4735000000.0-4638000000.0-2711000000.0-4589000000.0-4552000000.0-4766000000.0-2796000000.0
Percentage of AirTrafficLiabilityRevenuefromCurrentPeriodSales100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AmountOfDeferredRevenueFromVendorPrepaymentThatWouldHaveBeenReceivableAtPeriodEnd

luv:AmountOfDeferredRevenueFromVendorPrepaymentThatWouldHaveBeenReceivableAtPeriodEnd


Amount
Period End2021-03-31
Value106
Percentage of AmountOfDeferredRevenueFromVendorPrepaymentThatWouldHaveBeenReceivableAtPeriodEnd100.0

luv:AssetsConstructedForOthersDuringPeriod

luv:AssetsConstructedForOthersDuringPeriod


Assets
Period End2021-06-302020-06-30
Value-341.041
Percentage of AssetsConstructedForOthersDuringPeriod100.0100.0

luv:AssetsConstructedforOthersDuringPeriod

luv:AssetsConstructedforOthersDuringPeriod


Assets
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value3235354134-8.0282421454640407039385031505560664637432927191315154728
Percentage of AssetsConstructedforOthersDuringPeriod100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:CapitalizedFinancingItems

luv:CapitalizedFinancingItems


Capitalized
Period End2020-12-312020-09-302020-06-30
Value-1.044171
Percentage of CapitalizedFinancingItems100.0100.0100.0

luv:CashRaisedNetOfFees

luv:CashRaisedNetOfFees


Cash
Period End2020-12-31
Value0.0
Percentage of CashRaisedNetOfFees0.0

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramAwardedPoints

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramAwardedPoints


Contract
Period End2021-06-302020-06-30
Value656385
Percentage of ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramAwardedPoints100.0100.0

luv:ContractWithCustomerLiabilityLoyaltyProgramRevenueRecognized us-gaap:MajorCustomers

luv:ContractWithCustomerLiabilityLoyaltyProgramRevenueRecognized

luv:PassengerCustomers


Contract
Period End2021-06-302020-06-30
Value-549000000.0-81000000.0
Percentage of ContractWithCustomerLiabilityLoyaltyProgramRevenueRecognized100.0100.0

us-gaap:OtherCustomer


Contract
Period End2021-06-302020-06-30
Value-11000000.0-9000000.0
Percentage of ContractWithCustomerLiabilityLoyaltyProgramRevenueRecognized2.011.1

luv:ConvertibleDebtConversionTermsMeasurementPeriodTradingPriceThresholdPercentage us-gaap:DebtInstrument

luv:ConvertibleDebtConversionTermsMeasurementPeriodTradingPriceThresholdPercentage

luv:A1250ConvertibleSeniorNotesDue2025


Convertible
Period End2020-09-30
Value98.0
Percentage of ConvertibleDebtConversionTermsMeasurementPeriodTradingPriceThresholdPercentage100.0

luv:ConvertibleDebtConversionTermsPercentageOfSalesPriceExceedingConversionPrice us-gaap:DebtInstrument

luv:ConvertibleDebtConversionTermsPercentageOfSalesPriceExceedingConversionPrice

luv:A1250ConvertibleSeniorNotesDue2025


Convertible
Period End2020-09-30
Value130.0
Percentage of ConvertibleDebtConversionTermsPercentageOfSalesPriceExceedingConversionPrice100.0

luv:CostsIncurredForVoluntarySeparation2020AndExtendedETO

luv:CostsIncurredForVoluntarySeparation2020AndExtendedETO


Costs
Period End2020-09-30
Value1100
Percentage of CostsIncurredForVoluntarySeparation2020AndExtendedETO100.0

luv:DeferredRevenueRelatedToVendorPrepayment

luv:DeferredRevenueRelatedToVendorPrepayment


Deferred
Period End2021-03-31
Value323
Percentage of DeferredRevenueRelatedToVendorPrepayment100.0

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThrough2020 us-gaap:UnusualOrInfrequentItem

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThrough2020

luv:COVID19


Extended
Period End2021-06-302021-03-31
Value436348
Percentage of ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThrough2020100.0100.0

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughMarch312021

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughMarch312021


Extended
Period End2021-03-31
Value26
Percentage of ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughMarch312021100.0

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughSeptember302020

luv:ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughSeptember302020


Extended
Period End2020-09-30
Value613
Percentage of ExtendedEmergencyTimeOffAccrualForEmployeesWhoAcceptedThroughSeptember302020100.0

luv:ExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020

luv:ExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020


Extended
Period End2020-09-30
Value-25000000.0
Percentage of ExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020100.0

luv:ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch312021

luv:ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch312021


Extended
Period End2021-03-31
Value141
Percentage of ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch312021100.0

luv:ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch312021 us-gaap:UnusualOrInfrequentItem

luv:COVID19


Extended
Period End2021-06-302021-03-31
Value15115
Percentage of ExtendedEmergencyTimeOffReversalForEmployeesWhoAcceptedThroughMarch3120210.081.6

luv:FlightEquipmentAcquiredAgainstSupplierCredit

luv:FlightEquipmentAcquiredAgainstSupplierCredit


Flight
Period End2021-06-30
Value207
Percentage of FlightEquipmentAcquiredAgainstSupplierCredit100.0

luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedDecember312020 us-gaap:AircraftType

luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedDecember312020

luv:B737MAX8


Leased
Period End2020-12-31
Value7.0
Percentage of LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedDecember312020100.0

luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedMarch312021 us-gaap:AircraftType

luv:LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedMarch312021

luv:B737MAX8


Leased
Period End2021-03-31
Value8.0
Percentage of LeasedAircraftDeliveredFromThirdPartiesDuringTheThreeMonthsEndedMarch312021100.0

luv:LongTermPurchaseCommitmentsAdditionalMAX8s luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType

luv:LongTermPurchaseCommitmentsAdditionalMAX8s

luv:CurrentYear2021, luv:B737MAX8


Long
Period End2021-03-31
Value9.0
Percentage of LongTermPurchaseCommitmentsAdditionalMAX8s100.0

luv:LongTermPurchaseCommitmentsAdditionalMAX8s us-gaap:AircraftType

luv:B737MAX8


Long
Period End2021-03-31
Value9.0
Percentage of LongTermPurchaseCommitmentsAdditionalMAX8s100.0

luv:LongTermPurchaseCommitmentsAndOptionsTotal luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType

luv:LongTermPurchaseCommitmentsAndOptionsTotal

luv:CurrentYear2021, srt:B737Max


Long
Period End2021-03-31
Value28.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal100.0

luv:YearEight2028, srt:B737Max


Long
Period End2021-03-31
Value60.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal214.3

luv:YearEleven2031, srt:B737Max


Long
Period End2021-03-31
Value10.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal35.7

luv:YearFive2025, srt:B737Max


Long
Period End2021-03-31
Value70.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal250.0

luv:YearFour2024, srt:B737Max


Long
Period End2021-03-31
Value70.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal250.0

luv:YearNine2029, srt:B737Max


Long
Period End2021-03-31
Value60.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal214.3

luv:YearSeven2027, srt:B737Max


Long
Period End2021-03-31
Value60.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal214.3

luv:YearSix2026, srt:B737Max


Long
Period End2021-03-31
Value70.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal250.0

luv:YearTen2030, srt:B737Max


Long
Period End2021-03-31
Value60.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal214.3

luv:YearThree2023, srt:B737Max


Long
Period End2021-03-31
Value68.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal242.9

luv:YearTwo2022, srt:B737Max


Long
Period End2021-03-31
Value72.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal257.1

luv:LongTermPurchaseCommitmentsAndOptionsTotal us-gaap:AircraftType

srt:B737Max


Long
Period End2021-03-31
Value628.0
Percentage of LongTermPurchaseCommitmentsAndOptionsTotal2242.9

luv:LongTermPurchaseOptionsQuantity luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType

luv:LongTermPurchaseOptionsQuantity

luv:YearEight2028, srt:B737Max


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseOptionsQuantity100.0

luv:YearFive2025, srt:B737Max


Long
Period End2021-03-31
Value40.0
Percentage of LongTermPurchaseOptionsQuantity133.3

luv:YearFour2024, srt:B737Max


Long
Period End2021-03-31
Value40.0
Percentage of LongTermPurchaseOptionsQuantity133.3

luv:YearNine2029, srt:B737Max


Long
Period End2021-03-31
Value10.0
Percentage of LongTermPurchaseOptionsQuantity33.3

luv:YearSeven2027, srt:B737Max


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseOptionsQuantity100.0

luv:YearSix2026, srt:B737Max


Long
Period End2021-03-31
Value40.0
Percentage of LongTermPurchaseOptionsQuantity133.3

luv:YearThree2023, srt:B737Max


Long
Period End2021-03-31
Value38.0
Percentage of LongTermPurchaseOptionsQuantity126.7

luv:YearTwo2022, srt:B737Max


Long
Period End2021-03-31
Value42.0
Percentage of LongTermPurchaseOptionsQuantity140.0

luv:LongTermPurchaseOptionsQuantity us-gaap:AircraftType

srt:B737Max


Long
Period End2021-03-31
Value270.0
Percentage of LongTermPurchaseOptionsQuantity900.0

luv:OtherRevenueRecognizedFromPointsRedeemed

luv:OtherRevenueRecognizedFromPointsRedeemed


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value-12000000.0-16000000.0-16000000.0-9000000.0-19000000.0-27000000.0-20000000.0-17000000.0-16000000.0-22000000.0-17000000.0-11000000.0-11000000.0-15000000.0-9000000.0-4000000.0
Percentage of OtherRevenueRecognizedFromPointsRedeemed100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:OwnedAircraftDeliveredDuringTheThreeMonthsEndedMarch312021 us-gaap:AircraftType

luv:OwnedAircraftDeliveredDuringTheThreeMonthsEndedMarch312021

luv:B737MAX8


Owned
Period End2021-03-31
Value12.0
Percentage of OwnedAircraftDeliveredDuringTheThreeMonthsEndedMarch312021100.0

luv:PSP3PayrollSupportProgramAmountOfGrantExpectedToBeAllocatedInThirdQuarter2021

luv:PSP3PayrollSupportProgramAmountOfGrantExpectedToBeAllocatedInThirdQuarter2021


P
Period End2021-03-31
Value1300
Percentage of PSP3PayrollSupportProgramAmountOfGrantExpectedToBeAllocatedInThirdQuarter2021100.0

luv:PassengerRevenueRecognizedFromPointsRedeemed

luv:PassengerRevenueRecognizedFromPointsRedeemed


Passenger
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value-278000000.0-256000000.0-205000000.0-81000000.0-461000000.0-673000000.0-657000000.0-622000000.0-535000000.0-605000000.0-623000000.0-588000000.0-491000000.0-539000000.0-616000000.0-602000000.0
Percentage of PassengerRevenueRecognizedFromPointsRedeemed100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:PaymentsOfTerminatedInterestRateDerivativeInstruments

luv:PaymentsOfTerminatedInterestRateDerivativeInstruments


Payments
Period End2020-12-312020-09-30
Value-90.031
Percentage of PaymentsOfTerminatedInterestRateDerivativeInstruments100.0100.0

luv:PayrollSupportAndVoluntaryEmployeeProgramsNet

luv:PayrollSupportAndVoluntaryEmployeeProgramsNet


Payroll
Period End2021-06-302021-03-312020-12-312020-09-302020-06-30
Value740-1448.0-34.0-149.0784
Percentage of PayrollSupportAndVoluntaryEmployeeProgramsNet100.0100.0100.0100.0100.0

luv:PayrollSupportAndVoluntaryEmployeeProgramsNet us-gaap:CounterpartyName, us-gaap:StatementScenario, us-gaap:SubsequentEventType

luv:UnitedStatesDepartmentOfTreasury, srt:ScenarioForecast, us-gaap:SubsequentEvent


Payroll
Period End2021-09-30
Value763
Percentage of PayrollSupportAndVoluntaryEmployeeProgramsNet0.0

luv:PayrollSupportAndVoluntaryEmployeeProgramsNet us-gaap:Restatement, us-gaap:ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementByRestatementPeriodAndAmount

srt:RevisionOfPriorPeriodErrorCorrectionAdjustment, luv:UnderaccruedPayrollTaxCredits


Payroll
Period End2020-12-31
Value88
Percentage of PayrollSupportAndVoluntaryEmployeeProgramsNet-258.8

luv:Percentageofactualconsumptionhedged

luv:Percentageofactualconsumptionhedged


Percentageofactualconsumptionhedged
Period End2020-12-312020-09-302020-06-302019-09-302019-06-302018-09-302018-06-302017-09-302017-06-30
Value10.042.00.950.660.780.80.760.610.6
Percentage of Percentageofactualconsumptionhedged100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:ProceedsFromGrants us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

luv:ProceedsFromGrants

luv:UnitedStatesDepartmentOfTreasury, luv:AmericanRescuePlanActOf2021


Proceeds
Period End2021-06-032021-06-302021-04-23
Value6401310670
Percentage of ProceedsFromGrants100.0100.0100.0

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Proceeds
Period End2021-04-232021-03-052021-01-15
Value177591625
Percentage of ProceedsFromGrants26.40.00.0

luv:UnitedStatesDepartmentOfTreasury, luv:CoronavirusAidReliefAndEconomicSecurityAct


Proceeds
Period End2020-09-302020-07-302020-06-302020-05-292020-04-21
Value642254484481152
Percentage of ProceedsFromGrants0.00.00.00.00.0

luv:ProceedsFromGrantsNotesPayableAndWarrants us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

luv:ProceedsFromGrantsNotesPayableAndWarrants

luv:UnitedStatesDepartmentOfTreasury, luv:AmericanRescuePlanActOf2021


Proceeds
Period End2021-06-032021-04-232021-06-30
Value9269261900
Percentage of ProceedsFromGrantsNotesPayableAndWarrants100.0100.0100.0

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Proceeds
Period End2021-04-232021-03-052021-01-15
Value259864864
Percentage of ProceedsFromGrantsNotesPayableAndWarrants28.00.00.0

luv:UnitedStatesDepartmentOfTreasury, luv:CoronavirusAidReliefAndEconomicSecurityAct


Proceeds
Period End2020-09-302020-07-302020-06-302020-05-292020-04-21
Value943266526521630
Percentage of ProceedsFromGrantsNotesPayableAndWarrants0.00.00.00.00.0

luv:ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits

luv:ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits


Proceeds
Period End2021-03-31
Value1200
Percentage of ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits100.0

luv:ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits us-gaap:UnusualOrInfrequentItem

luv:COVID19


Proceeds
Period End2021-06-30
Value724
Percentage of ProceedsFromPSP2PayrollSupportProgramExtensionGrantAllocatedToFundSalariesWagesAndBenefits0.0

luv:ProceedsFromPayrollSupportProgramGrantAllocatedToFundSalariesWagesAndBenefits

luv:ProceedsFromPayrollSupportProgramGrantAllocatedToFundSalariesWagesAndBenefits


Proceeds
Period End2020-09-30
Value1200
Percentage of ProceedsFromPayrollSupportProgramGrantAllocatedToFundSalariesWagesAndBenefits100.0

luv:ProceedsFromPayrollSupportProgramLoansAndWarrants

luv:ProceedsFromPayrollSupportProgramLoansAndWarrants


Proceeds
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-06-30
Value6255110.01308850.0
Percentage of ProceedsFromPayrollSupportProgramLoansAndWarrants100.0100.00.0100.0100.00.0

luv:RepaymentOfShortTermDebt us-gaap:DebtInstrument

luv:RepaymentOfShortTermDebt

luv:A364DayTermLoanCreditFacility


Repayment
Period End2020-12-312020-09-302020-06-302019-06-30
Value00-3683000000.00
Percentage of RepaymentOfShortTermDebt0.00.0100.00.0

luv:RevenueAmountsDeferredAssociatedWithPointsAwarded

luv:RevenueAmountsDeferredAssociatedWithPointsAwarded


Revenue
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value466470447385656746727757711690669719634639621632
Percentage of RevenueAmountsDeferredAssociatedWithPointsAwarded100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:SaleLeasebackCashProceedsInvesting

luv:SaleLeasebackCashProceedsInvesting


Sale
Period End2020-12-312020-09-302020-06-302019-06-30
Value0.00.08150.0
Percentage of SaleLeasebackCashProceedsInvesting0.00.0100.00.0

luv:SupplierProceeds

luv:SupplierProceeds


Supplier
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value8560.0-128.0-300.00.00.0
Percentage of SupplierProceeds100.00.0100.0100.00.00.0

luv:TotalAircraftDeliveredDuringTheThreeMonthsEndedMarch312021 us-gaap:AircraftType

luv:TotalAircraftDeliveredDuringTheThreeMonthsEndedMarch312021

luv:B737MAX8


Total
Period End2021-03-31
Value20.0
Percentage of TotalAircraftDeliveredDuringTheThreeMonthsEndedMarch312021100.0

luv:TotalOperatingLeasedAircraftToBeDeliveredIn2020And2021FromThirdParties us-gaap:AircraftType

luv:TotalOperatingLeasedAircraftToBeDeliveredIn2020And2021FromThirdParties

luv:B737MAX8


Total
Period End2021-03-31
Value16.0
Percentage of TotalOperatingLeasedAircraftToBeDeliveredIn2020And2021FromThirdParties100.0

luv:UnusedFundsConvertedToLoyaltyPoints

luv:UnusedFundsConvertedToLoyaltyPoints


Unused
Period End2020-12-312020-09-30
Value62105
Percentage of UnusedFundsConvertedToLoyaltyPoints100.0100.0

luv:VoluntarySeparationProgram2020AccrualForEmployeesWhoAcceptedAfterJune302020

luv:VoluntarySeparationProgram2020AccrualForEmployeesWhoAcceptedAfterJune302020


Voluntary
Period End2020-09-30
Value485
Percentage of VoluntarySeparationProgram2020AccrualForEmployeesWhoAcceptedAfterJune302020100.0

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020


Voluntary
Period End2020-09-30
Value-198000000.0
Percentage of VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffReductionForEmployeesWhoAcceptedThroughSeptember302020100.0

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffRelievedFromAccrualForEmployeesWhoAcceptedThroughMarch312021

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffRelievedFromAccrualForEmployeesWhoAcceptedThroughMarch312021


Voluntary
Period End2021-03-31
Value188
Percentage of VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffRelievedFromAccrualForEmployeesWhoAcceptedThroughMarch312021100.0

luv:VoluntarySeparationProgram2020ReductionForEmployeesWhoAcceptedAfterJune302020

luv:VoluntarySeparationProgram2020ReductionForEmployeesWhoAcceptedAfterJune302020


Voluntary
Period End2020-09-30
Value-173000000.0
Percentage of VoluntarySeparationProgram2020ReductionForEmployeesWhoAcceptedAfterJune302020100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-30
Value22235.035
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalWarrantIssued us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Adjustments
Period End2021-06-302021-03-312020-09-302020-06-30
Value22235.035
Percentage of AdjustmentsToAdditionalPaidInCapitalWarrantIssued100.0100.0100.0100.0

us-gaap:AircraftMaintenanceMaterialsAndRepairs

us-gaap:AircraftMaintenanceMaterialsAndRepairs


Aircraft
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value2221731531851402723073133102932932832742572432632512432442582802622762592402292442482362502382712812912703002912729540.0002720.0002461997500.0001960.000194
Percentage of AircraftMaintenanceMaterialsAndRepairs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal

luv:A1250ConvertibleSeniorNotesDue2025, us-gaap:ConvertibleDebt


Debt
Period End2021-06-302021-03-31
Value874881
Percentage of DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal100.0100.0

us-gaap:DebtInstrumentRedemptionPricePercentage us-gaap:DebtInstrument

us-gaap:DebtInstrumentRedemptionPricePercentage

luv:A1250ConvertibleSeniorNotesDue2025


Debt
Period End2020-12-31
Value100.0
Percentage of DebtInstrumentRedemptionPricePercentage100.0

us-gaap:DepreciationAndAmortization

us-gaap:DepreciationAndAmortization


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
Value3153123153153133113133083022973313012922772793023193183183152992902642582502442512382282212242212132102242172022017140.0001910.0001761556270.0001610.000154154
Percentage of DepreciationAndAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:DerivativeCostOfHedge

us-gaap:CommodityContract, us-gaap:DesignatedAsHedgingInstrument, us-gaap:OperatingExpense


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value141413131324202028
Percentage of DerivativeCostOfHedge100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommodityContract, us-gaap:NotDesignatedAsHedgingInstrumentEconomicHedge, us-gaap:GainLossOnDerivativeInstruments


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-06-30
Value10.0111211110.0
Percentage of DerivativeCostOfHedge71.478.692.384.684.60.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:DerivativeGainLossOnDerivativeNet

us-gaap:CommodityContract, us-gaap:Nondesignated, us-gaap:OtherNonoperatingIncomeExpense


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-30
Value125.01.0-1.0-1.00.0-76.0-114.0-239.0-71.0-19.0-245.0-39.0-16.055-22.093
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:Nondesignated, us-gaap:OtherNonoperatingIncomeExpense


Derivative
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.01.0-5.0-24.00.00.00.00.00.00.01.01.0
Percentage of DerivativeGainLossOnDerivativeNet0.0-100.0500.00.00.00.00.00.00.00.00.00.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:Nondesignated, us-gaap:OtherNonoperatingIncomeExpense


Derivative
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-06-30
Value125.01.0-60.06.0-24.00.0
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.06000.0-600.00.00.0

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet

us-gaap:CommodityContract, us-gaap:CashFlowHedging, srt:Fuel


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value16-124.01814-22.0-20.0-19.0-2.0-11.01.020
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:InterestExpense


Derivative
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-2.00.01.00.0-2.0-2.0-1.0-1.0-2.0-1.0-1.0-2.0-3.0-2.0-3.0-3.0
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet1.60.07.1-0.010.010.550.09.1-200.0-5.00.00.00.00.00.00.0

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:OperatingExpense


Derivative
Period End2021-03-31
Value1.0
Percentage of DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet6.2

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate

us-gaap:EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate


Effective
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value1.925.63-0.0730.3430.221.7660.0030.231
Percentage of EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci luv:CommodityContractType, luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci

us-gaap:CommodityOption, us-gaap:CommodityContract


Fair
Period End2021-03-312020-12-312020-09-302020-06-30
Value11632-1.019
Percentage of FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci100.0100.0100.0100.0

us-gaap:FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Fair
Period End2021-06-30
Value246
Percentage of FairValueAssetRecurringBasisStillHeldUnrealizedGainLossOci0.0

us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings

us-gaap:CommodityContract


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-11.01.00.02315-11.0-10.057-303.0-46.0208-34.01059-405.085-93.0416-82.03669-71.062-16.0-27.04711183-179.0
Percentage of FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Fair
Period End2021-06-30
Value12
Percentage of FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarnings-109.1

us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss luv:CommodityContractType, luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

us-gaap:CommodityOption, us-gaap:CommodityContract


Fair
Period End2021-03-312020-12-312020-09-302020-06-30
Value-2.014-21.0-8.0
Percentage of FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss100.0100.0100.0100.0

us-gaap:FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Fair
Period End2021-06-30
Value12
Percentage of FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss0.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

us-gaap:CommodityContract


Fair
Period End2020-12-312020-09-302020-06-302020-03-312018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value112411839.0382546306159719840818262226777921357268618959579157172
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

us-gaap:CommodityContract


Fair
Period End2021-03-312018-06-302017-12-312017-09-302017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-31
Value-1.0-49.0-998.0158166-1515.0246148239-547.0182-39.05.08.07.0-49.00.0-24.0-23.0-20.0464014
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Fair
Period End2021-06-302019-06-302018-09-30
Value-9.0-30.0-57.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements0.00.00.0

us-gaap:FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci luv:FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliation

us-gaap:FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci

us-gaap:CommodityContract


Fair
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value250117141.026-106.0
Percentage of FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci100.0100.0100.0100.0100.0100.0

us-gaap:FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci us-gaap:DerivativeInstrumentRisk

us-gaap:CommodityContract


Fair
Period End2021-06-30
Value250
Percentage of FairValueRecurringBasisUnobservableInputReconciliationAssetLiabilityGainLossOci100.0

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
Value8034693423792578701105109011361015119112051202101810251003990922951941903852798936100587711681386142513141367145014891457150515281577151056430.0015860.001527103836190.0009260.000933821
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 luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Fuel
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302013-09-30
Value1616181422-158.0-139.01742-224.0-236.0-310.0-126.0-65.0-72.0-6.02.0-37.0
Percentage of FuelCosts3.44.74.75.42.5-16.0-15.1183.2-23.8-26.1-36.4-13.5-6.5-8.2-0.40.1-2.6

us-gaap:FuelCosts us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Fuel
Period End2021-06-30
Value12
Percentage of FuelCosts1.5

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

us-gaap:GainLossOnDerivativeInstrumentsNetPretax

us-gaap:InterestRateSwap, us-gaap:FairValueHedging, us-gaap:DesignatedAsHedgingInstrument, us-gaap:InterestExpense


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-30
Value0.02.02.02.0-1.00.00.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.0100.0100.0100.0100.00.00.0

us-gaap:GainLossOnDerivativeInstrumentsNetPretax us-gaap:IncomeStatementLocation

luv:FuelAndOil


Gain
Period End2021-06-302020-06-30
Value1214
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.0700.0

srt:Fuel


Gain
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-16.0-16.0-18.0-14.0-22.0-20.0-19.02.0-11.01.020
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.00.0-900.0-700.0-1100.02000.00.00.00.00.00.0

us-gaap:GainLossOnDerivativeInstruments


Gain
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-31
Value12-6.0-1.0-22.0-14.0-2.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.00.00.0-1100.0-700.0-100.0

us-gaap:InterestExpense


Gain
Period End2020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value0.0-2.0-3.0-2.0-8.0-8.0-7.0-8.0-11.0-9.0-9.0-10.0-10.0-7.0-8.0-8.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.0-100.0-150.0-100.0800.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingExpense


Gain
Period End2021-06-302021-03-31
Value1.0-1.0
Percentage of GainLossOnDerivativeInstrumentsNetPretax0.00.0

us-gaap:GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments

us-gaap:InterestRateSwap, us-gaap:Nondesignated


Gain
Period End2020-12-312020-09-302020-06-30
Value561.05.0
Percentage of GainLossOnInterestRateDerivativeInstrumentsNotDesignatedAsHedgingInstruments100.0100.0100.0

us-gaap:IncreaseDecreaseCashCollateralFromCounterparties

us-gaap:IncreaseDecreaseCashCollateralFromCounterparties


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value48387.0-5.012-5.0250.0-15.015-165.010.07565301519937305114347-231.0-357.0181-377.0-17.0-241.0-98.095111.080-53.02815252-181.0147-194.999571-0.000409-4.9e-05292641.5e-050.00013
Percentage of IncreaseDecreaseCashCollateralFromCounterparties100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables

us-gaap:IncreaseDecreaseInAccountsAndOtherReceivables


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value563234234123119-183.0-198.088-18.0222-226.0138115790.0-12.035-305.032014212.0-4.0-41.0130-137.022-10.072-57.0-73.05197-74.02.03768261.1e-05-2.1e-05-87.0-25.9999344.2e-05-4.2e-05-67.0
Percentage of IncreaseDecreaseInAccountsAndOtherReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities

us-gaap:IncreaseDecreaseInAccountsPayableAndAccruedLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value989-66.0296261200-1291.0538106-89.0-257.0465161420-501.040289-338.093-46.0247-288.0313537380-134.0177122-534.042424158-98.016212072-187.077225252-3.9e-056.7e-05238192-5e-060.000279-85.0
Percentage of IncreaseDecreaseInAccountsPayableAndAccruedLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap: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
Value94659939216667701-457.0-17.0-30.0944
Percentage of IncreaseDecreaseInContractWithCustomerLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value30-5.018829818149279-174.03613-609.010413172999826962-850.03155426
Percentage of IncreaseDecreaseInDeferredIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingAssets


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-16.011-49.0-84.0-224.0-58.0-44.0-79.0-86.0-29.0-16.03035178-2.06411981581649-4.0-63.0-33.07.0-13.0-149.0-6.021-7.0-37.063-6.025-60.07439511642
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities


Increase
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-64000000.0-122000000.06000000.0-106000000.0-74000000.0-132000000.0-67000000.0-87000000.0-54000000.0-69000000.00000
Percentage of IncreaseDecreaseInOtherOperatingLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:IncrementalCommonSharesAttributableToConversionOfDebtSecurities

us-gaap:IncrementalCommonSharesAttributableToConversionOfDebtSecurities


Incremental
Period End2021-06-302021-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302011-12-312011-09-302011-06-302010-06-30
Value22160.00.00.00.0-1.06.06.06.00.06.06.06.00.06.06.06.00.06.06.00.00.00.06.00.00.06e-061e-06
Percentage of IncrementalCommonSharesAttributableToConversionOfDebtSecurities100.0100.00.00.00.00.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.00.00.00.0100.00.00.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements


Incremental
Period End2021-06-302021-03-312020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value1000000.01000000.0001000000.001000000.0001000000.01000000.01000000.01000000.01000000.01000000.0-1000000.01000000.01000000.01000000.002000000.02000000.02000000.002000000.02000000.03000000.002000000.02000000.02000000.01000000.01000000.01000000.01000000.01000000.001.01000000.001.001000000.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.00.00.0100.00.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0100.00.0100.0

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
Value8.01112117.05.09.010.09.09.09.09.010.010.011151311131211118.09.07.06.05.06.06.07.07.04.08.05.0
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 End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value116114114111962828303131
Percentage of InterestCostsIncurred100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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
Value2.02.02.04.09.0172023242322201512119.08.07.07.06.06.05.04.02.02.01.02.02.02.02.01.01.02.02.02.02.02.02.09.9999921e-064e-06-3.0-12.0000092e-064e-06-3.0
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:LaborAndRelatedExpense

us-gaap:LaborAndRelatedExpense


Labor
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value1825157115661678171418542247200220681976199019121927182119241795186717331709190916391539165816991607141913901363140612751284127112981183119711891222114143700.0011460.00112595437030.0009380.000946
Percentage of LaborAndRelatedExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LandingFeesAndOtherRentals

us-gaap:LandingFeesAndOtherRentals


Landing
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-31
Value4033133183082753393273453573333233373443303233243323132933073093022793032992852622892952662552902922662522782602549580.0002570.0002472018060.000210.000206190
Percentage of LandingFeesAndOtherRentals100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LongTermPurchaseCommitmentMinimumQuantityRequired luv:LongTermPurchaseCommitmentByYear, us-gaap:AircraftType

us-gaap:LongTermPurchaseCommitmentMinimumQuantityRequired

luv:CurrentYear2021, luv:B737MAX8


Long
Period End2021-03-31
Value19.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired100.0

luv:YearEight2028, luv:B737MAX7


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearEight2028, luv:B737MAX8


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearEleven2031, luv:B737MAX8


Long
Period End2021-03-31
Value10.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired52.6

luv:YearFive2025, luv:B737MAX7


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired157.9

luv:YearFour2024, luv:B737MAX7


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired157.9

luv:YearNine2029, luv:B737MAX7


Long
Period End2021-03-31
Value20.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired105.3

luv:YearNine2029, luv:B737MAX8


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired157.9

luv:YearSeven2027, luv:B737MAX7


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearSeven2027, luv:B737MAX8


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearSix2026, luv:B737MAX7


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearSix2026, luv:B737MAX8


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearTen2030, luv:B737MAX7


Long
Period End2021-03-31
Value15.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired78.9

luv:YearTen2030, luv:B737MAX8


Long
Period End2021-03-31
Value45.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired236.8

luv:YearThree2023, luv:B737MAX7


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired157.9

luv:YearTwo2022, luv:B737MAX7


Long
Period End2021-03-31
Value30.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired157.9

us-gaap:LongTermPurchaseCommitmentMinimumQuantityRequired us-gaap:AircraftType

luv:B737MAX7


Long
Period End2021-03-31
Value200.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired1052.6

luv:B737MAX8


Long
Period End2021-03-31
Value149.0
Percentage of LongTermPurchaseCommitmentMinimumQuantityRequired784.2

us-gaap:LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship, us-gaap:IncomeStatementLocation

us-gaap:LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring

us-gaap:CommodityContract, us-gaap:CashFlowHedging, us-gaap:GainLossOnDerivativeInstruments


Loss
Period End2021-03-312020-12-312020-09-302020-06-302020-03-31
Value6.01.022142.0
Percentage of LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring100.0100.0100.0100.0100.0

us-gaap:LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:CommodityContract, us-gaap:Nondesignated


Loss
Period End2020-12-312020-09-302020-06-302020-03-31
Value1.022142.0
Percentage of LossOnDiscontinuationOfCashFlowHedgeDueToForecastedTransactionProbableOfNotOccurring100.0100.0100.0100.0

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent


Oci
Period End2021-06-30
Value186
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent100.0

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Oci
Period End2021-06-30
Value250
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent134.4

us-gaap:InterestRateContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Oci
Period End2021-06-30
Value-7.0
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent-3.8

us-gaap:OciBeforeReclassificationsNetOfTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Oci
Period End2021-06-30
Value-57.0
Percentage of OciBeforeReclassificationsNetOfTaxAttributableToParent-30.6

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

luv:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesInterestRateDerivative


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value123.00.0-42.0-22.0-20.0-15.00.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax100.0100.00.0100.0100.0100.0100.00.0

luv:OtherComprehensiveIncomeOtherChangesNetOfTax


Other
Period End2020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value1433-37.02.06.0147.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax466.70.088.1-9.1-30.0-93.30.0

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value109-21.011-108.0-123.0-71.087159
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax908.3-700.00.0257.1559.1355.0-580.00.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value-28.01.0-10.0433320-19.0-38.0
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax-233.333.30.0-102.4-150.0-100.0126.70.0

us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-30
Value93-3.034-144.0-110.0-65.067128
Percentage of OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax775.0-100.00.0342.9500.0325.0-446.70.0

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax us-gaap:DerivativeInstrumentRisk

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax

us-gaap:CommodityContract


Other
Period End2021-06-302020-06-30
Value20130
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax100.0100.0

us-gaap:InterestRateContract


Other
Period End2021-06-302020-06-30
Value-5.01.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax-2.53.3

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax us-gaap:DerivativeInstrumentRisk

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax

us-gaap:CommodityContract


Other
Period End2021-06-302020-06-30
Value619.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax100.0100.0

us-gaap:InterestRateContract


Other
Period End2021-06-30
Value-1.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax-1.6

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax

us-gaap:CommodityContract, us-gaap:CashFlowHedging


Other
Period End2021-06-302020-06-30
Value-192.0-9.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax100.0100.0

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging


Other
Period End2021-06-30
Value6.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax-3.1

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

us-gaap:CommodityContract, us-gaap:CashFlowHedging, luv:FuelAndOil


Other
Period End2021-06-302020-06-30
Value-12.0-14.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax6.2155.6

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging, us-gaap:OperatingExpense


Other
Period End2021-06-30
Value-1.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax0.5

us-gaap:OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:CashFlowHedging


Other
Period End2021-06-302020-06-30
Value-186.0-9.0
Percentage of OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax96.9100.0

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax us-gaap:DerivativeInstrumentRisk

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value1011430-65.0-80.0-56.07610721681123
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value10.04.03.01.0-32.015-15.0-15.0-11.01.01.01.03.02.02.0
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax9.90.021.43.349.20.018.826.8-14.50.00.90.53.70.01.6

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax us-gaap:DerivativeInstrumentRisk

us-gaap:OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax

us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-30
Value305.09.0-19.0-24.0-17.02232662573
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3.01.01.00.0-10.05.0-5.0-4.0-3.00.00.01.00.02.00.0
Percentage of OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesTax10.00.020.00.052.60.020.823.5-13.60.00.01.50.00.00.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


Other
Period End2021-06-302021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302016-09-302016-06-302015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value196-47.01125-28.02.05.0116.03.00.02.02.03.00.0-3.00.00.01.02.02.03.00.03.06.0-4.02.0-4.03.03.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.00.0100.00.00.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossTaxPortionAttributableToParent1

us-gaap:OtherComprehensiveIncomeLossTaxPortionAttributableToParent1


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-30
Value-13000000.05000000.03000000.08000000.0-9000000.03000000.001000000.03000000.0-3000000.01000000.0003000000.02000000.0003000000.02000000.0001000000.0-2000000.000-4000000.01000000.01000000.01000000.01000000.02000000.002000000.0-10000000.03000000.0-3000000.02000000.00-3000000.0
Percentage of OtherComprehensiveIncomeLossTaxPortionAttributableToParent1100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.00.0100.0100.00.00.0100.0100.00.00.0100.0100.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax us-gaap:DerivativeInstrumentRisk, us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax

us-gaap:CommodityContract, us-gaap:CashFlowHedging


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-84.0-171.017-9.0-84.0-7.0-95.0-54.068-429.0122228787229
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:CashFlowHedging


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-9.0-56.0-3.00.0-32.014-17.0-16.0-12.0-1.00.01.01.01.0
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax10.732.7-17.6-0.038.1-200.017.929.6-17.60.20.00.41.31.4

us-gaap:OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax us-gaap:DerivativeInstrumentsGainLossByHedgingRelationship

us-gaap:CashFlowHedging


Other
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-93.0-227.014-9.0-116.07.0-112.0-70.0564301222297973
Percentage of OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax110.7132.782.4100.0138.1-100.0117.9129.682.4-100.2100.0100.4101.3101.4

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
Value58646352148822069876676276873075673973162566769968264266065861957861057256349757756853352657153251950153450950349018780.0005220.00047139614250.0003620.000327334
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:OtherCostAndExpenseOperating luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:InterestRateSwap, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Other
Period End2021-03-31
Value-1.0
Percentage of OtherCostAndExpenseOperating-0.2

us-gaap:OtherCostAndExpenseOperating us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:StatementEquityComponents

us-gaap:InterestRateContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Other
Period End2021-06-30
Value1.0
Percentage of OtherCostAndExpenseOperating0.2

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:OtherOperatingActivitiesCashFlowStatement


Other
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-31
Value17150.0-19.0-14.0-61.0-4.0-43.0-29.0-32.0-18.0730.0-40.0-32.0-8.0-37.0-44.0-37.0-43.0-35.0-49.0-66.0-308.0-52.0-35.0-236.0-26.02.0-17.0-6.0802.00.0
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:PaymentsToAcquireShortTermInvestments

us-gaap:PaymentsToAcquireShortTermInvestments


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
Value165113241199153613161029793529550251802678730200727531559563718641773256603506562316736415115977061589690072556366363362153610.0015250.001779-1484.0-5624.0043310.0011510.0018-1380.0
Percentage of PaymentsToAcquireShortTermInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PriorPeriodReclassificationAdjustment luv:TypeOfPriorPeriodAdjustment

us-gaap:PriorPeriodReclassificationAdjustment

luv:AdjustmentRelatedToUnderaccruedPayrollTaxCreditsIncludedInPayrollSupportAndOtherVoluntaryEmployeeProgramsNet


Prior
Period End2021-03-31
Value88
Percentage of PriorPeriodReclassificationAdjustment100.0

us-gaap:ProceedsFromConvertibleDebt

us-gaap:ProceedsFromConvertibleDebt


Proceeds
Period End2020-12-312020-09-302020-06-302019-06-30
Value0.00.023000.0
Percentage of ProceedsFromConvertibleDebt0.00.0100.00.0

us-gaap:ProceedsFromIssuanceOfCommonStock

us-gaap:ProceedsFromIssuanceOfCommonStock


Proceeds
Period End2020-12-312020-09-302020-05-012020-06-302019-06-30
Value0.00.0220022940.0
Percentage of ProceedsFromIssuanceOfCommonStock0.00.0100.0100.00.0

us-gaap:ProceedsFromIssuanceOfDebt

us-gaap:ProceedsFromIssuanceOfDebt


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.0112539975000.00.0
Percentage of ProceedsFromIssuanceOfDebt0.0100.0100.0100.00.00.0

us-gaap:ProceedsFromIssuanceOfWarrants us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

us-gaap:ProceedsFromIssuanceOfWarrants

luv:UnitedStatesDepartmentOfTreasury, luv:AmericanRescuePlanActOf2021


Proceeds
Period End2021-06-032021-06-302021-04-23
Value9.0189.0
Percentage of ProceedsFromIssuanceOfWarrants100.0100.0100.0

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Proceeds
Period End2021-04-232021-03-052021-01-15
Value4.0149.0
Percentage of ProceedsFromIssuanceOfWarrants44.40.00.0

luv:UnitedStatesDepartmentOfTreasury, luv:CoronavirusAidReliefAndEconomicSecurityAct


Proceeds
Period End2020-09-302020-07-302020-06-302020-05-292020-04-21
Value2.03.09.08.018
Percentage of ProceedsFromIssuanceOfWarrants0.00.00.00.00.0

us-gaap:ProceedsFromLinesOfCredit

us-gaap:ProceedsFromLinesOfCredit


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.00.010000.00.0
Percentage of ProceedsFromLinesOfCredit0.00.00.0100.00.00.0

us-gaap:ProceedsFromNotesPayable

us-gaap:ProceedsFromNotesPayable


Proceeds
Period End2020-12-312020-09-302020-06-302020-03-312019-06-302019-03-31
Value0.00.0268310000.00.0
Percentage of ProceedsFromNotesPayable0.00.0100.0100.00.00.0

us-gaap:ProceedsFromNotesPayable us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

luv:UnitedStatesDepartmentOfTreasury, luv:AmericanRescuePlanActOf2021


Proceeds
Period End2021-06-032021-06-302021-04-23
Value278526248
Percentage of ProceedsFromNotesPayable0.00.00.0

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Proceeds
Period End2021-04-232021-03-052021-01-15
Value78259229
Percentage of ProceedsFromNotesPayable0.00.00.0

luv:UnitedStatesDepartmentOfTreasury, luv:CoronavirusAidReliefAndEconomicSecurityAct


Proceeds
Period End2020-09-302020-07-302020-06-302020-05-292020-04-21
Value2897196196459
Percentage of ProceedsFromNotesPayable0.00.07.30.00.0

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
Value227.0202023-20.01.0-33.01.0-12.010.03.04.0-13.0-2.06.07.04.07.0-3.0-4.0-3.0-16.04.0-11.00.0-3.0-3.0-8.0-4.012-8.0-9.0-13.0-4.0-2.0-6.0-1.0-3.999996-2e-06-3e-061.07.9999951e-06-2e-060.0
Percentage of ProceedsFromPaymentsForOtherFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:ProceedsFromRepaymentsOfLinesOfCredit us-gaap:CreditFacility

us-gaap:ProceedsFromRepaymentsOfLinesOfCredit

us-gaap:RevolvingCreditFacility


Proceeds
Period End2020-12-312020-09-302020-06-302019-06-30
Value00-1000000000.00
Percentage of ProceedsFromRepaymentsOfLinesOfCredit0.00.0100.00.0

us-gaap:ProceedsFromStockPlans

us-gaap:ProceedsFromStockPlans


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
Value131312131311119.010.010.09.09.09.09.07.07.07.07.06.06.06.011169.08.013142325496512136.05.05.0125.0384e-062.7e-054.0541e-052.3e-0512
Percentage of ProceedsFromStockPlans100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax luv:AccumulatedOtherComprehensiveIncomeLossNetOfTax, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax

luv:UnrealizedGainOnDeferredCompensationPlanInvestment, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Reclassification
Period End2021-03-31
Value-60000000.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax us-gaap:StatementEquityComponents

luv:OtherComprehensiveIncomeOtherChangesNetOfTax


Reclassification
Period End2021-03-31
Value-60000000.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:DerivativeInstrumentRisk, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

us-gaap:CommodityContract, us-gaap:ReclassificationOutOfAccumulatedOtherComprehensiveIncome


Reclassification
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value221740282476-19.0-2.01120
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax us-gaap:StatementEquityComponents

luv:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesInterestRateDerivative


Reclassification
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-30
Value1.00.00.01.00.02.02.0-1.01.010.0-1.0-1.0-2.019-2.026-3.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax4.50.00.03.60.02.6-10.550.09.10.0-5.00.00.00.00.00.00.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Reclassification
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value8.0-4.0-9.0-7.0-5.0-6.0-4.00.0-3.00.05.03.0-1.0-375.0575952-655.084
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax36.4-23.5-22.5-25.0-20.8-7.921.1-0.0-27.30.025.00.00.00.00.00.00.00.00.0

us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest


Reclassification
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-30
Value-29.0133122191617-1.09.01.0-14.0-12.05.0644-96.0-102.0-90.01113-143.0-152.0-197.0426-82.0
Percentage of ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax-131.876.577.578.679.221.1-89.550.081.80.0-70.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent


Reclassification
Period End2021-06-30
Value10.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent100.0

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent us-gaap:DerivativeInstrumentRisk, us-gaap:StatementEquityComponents

us-gaap:CommodityContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Reclassification
Period End2021-06-30
Value12
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent120.0

us-gaap:InterestRateContract, us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedges


Reclassification
Period End2021-06-30
Value1.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent10.0

us-gaap:ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


Reclassification
Period End2021-06-30
Value-3.0
Percentage of ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent-30.0

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities

us-gaap:RepaymentsOfLongTermDebtAndCapitalSecurities


Repayments
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-30
Value43675445915978370707599879875825810659369352684856437940513944873464651521646148384315564.8e-053.2e-05301543.9e-052.5e-05
Percentage of RepaymentsOfLongTermDebtAndCapitalSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RepaymentsOfSeniorDebt us-gaap:DebtInstrument, us-gaap:LongtermDebtType, us-gaap:SubsequentEventType

us-gaap:RepaymentsOfSeniorDebt

luv:UnsecuredSeniorNotesDue2020, us-gaap:UnsecuredDebt, us-gaap:SubsequentEvent


Repayments
Period End2020-10-05
Value500
Percentage of RepaymentsOfSeniorDebt100.0

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability

us-gaap:RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability


Right
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value122182236.0661251006.05.0119
Percentage of RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:SaleAndLeasebackTransactionGainLossNet

us-gaap:SaleAndLeasebackTransactionGainLossNet


Sale
Period End2020-12-312020-09-302020-06-302019-06-30
Value0.00.0-222.00.0
Percentage of SaleAndLeasebackTransactionGainLossNet0.00.0100.00.0

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan


Stock
Period End2021-06-302020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value1313132.09.010.04.09.09.04.0
Percentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueEmployeeStockPurchasePlan us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


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
Value11-8.09.08.08.08.08.0-10.07.08.0-9.0
Percentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan84.60.069.261.5400.088.980.0-250.077.888.9-225.0

us-gaap:TreasuryStock


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
Value2.08.04.05.06.01.02.06.02.01.05.0
Percentage of StockIssuedDuringPeriodValueEmployeeStockPurchasePlan15.40.030.838.5300.011.120.0150.022.211.1125.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation


Stock
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-14.02.0-2.09.01213139.09.010.0
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital


Stock
Period End2021-03-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value-14.02.0-2.09.01213139.09.010.0
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:UnrealizedGainLossOnDerivatives

us-gaap:UnrealizedGainLossOnDerivatives


Unrealized
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-31
Value177.010.0-17.0-6.0-2.00.00.00.00.0-27.02.04.07.0-70.0426.0-27.0-301.067122-88.0285-87.0-74.0-11.0
Percentage of UnrealizedGainLossOnDerivatives100.0100.0100.0100.0100.0100.00.00.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

dei:EntityCommonStockSharesOutstanding

dei:EntityCommonStockSharesOutstanding


Entity
Period End2021-04-232021-02-042020-10-232020-07-23
Value591590590589
Percentage of EntityCommonStockSharesOutstanding100.0100.0100.0100.0

luv:AccrualforPropertyandIncomeTaxes

luv:AccrualforPropertyandIncomeTaxes


Accrualfor
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302018-12-31
Value1028084757267797068
Percentage of AccrualforPropertyandIncomeTaxes100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityLoyaltyProgram

luv:AirTrafficLiabilityLoyaltyProgram


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value46234447418738563561338533393289317130112948291927992667
Percentage of AirTrafficLiabilityLoyaltyProgram100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices

luv:AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value31092686290730232650212526272695284320592635261126311898
Percentage of AirTrafficLiabilityPassengerRevenueandAncillaryPassengerServices100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AirTrafficLiabilityTotal

luv:AirTrafficLiabilityTotal


Air
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value773271337094687962115510596659846014507055835530543045655023514251394221
Percentage of AirTrafficLiabilityTotal100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AircraftMaintenancePayable

luv:AircraftMaintenancePayable


Aircraft
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value7583959712915616210974676965545138333131262512875168162163170314310322336331299
Percentage of AircraftMaintenancePayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:AssetsConstructedForOthers

luv:AssetsConstructedForOthers


Assets
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value34130927423919816417214412017681718166416071543146014041319122011501067986915823745686621570515478453331
Percentage of AssetsConstructedForOthers100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:BusinessPartnersAndOtherSuppliers

luv:BusinessPartnersAndOtherSuppliers


Business
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value73274466434535779319
Percentage of BusinessPartnersAndOtherSuppliers100.0100.0100.0100.0100.0100.0100.0

luv:BusinessPartnersAndOtherSuppliersReceivablesCurrent

luv:BusinessPartnersAndOtherSuppliersReceivablesCurrent


Business
Period End2021-06-302020-12-31
Value380274
Percentage of BusinessPartnersAndOtherSuppliersReceivablesCurrent100.0100.0

luv:CapitalCommitmentsFrom2019ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020

luv:CapitalCommitmentsFrom2019ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020


Capital
Period End2020-12-31
Value743
Percentage of CapitalCommitmentsFrom2019ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020100.0

luv:CapitalCommitmentsFrom2020ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020

luv:CapitalCommitmentsFrom2020ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020


Capital
Period End2020-12-31
Value1300
Percentage of CapitalCommitmentsFrom2020ShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020100.0

luv:ConstructionObligationNoncurrent

luv:ConstructionObligationNoncurrent


Construction
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value341309274239198164172144120170116581613156313901311125811751078989903825757684632595554521468450437331
Percentage of ConstructionObligationNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgram

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgram


Contract
Period End2021-06-302021-03-312020-12-312020-06-302020-03-312019-12-31
Value471946234447385635613385
Percentage of ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgram100.0100.0100.0100.0100.0100.0

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramCustomerFundsExpiring

luv:ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramCustomerFundsExpiring


Contract
Period End2021-06-30
Value1500
Percentage of ContractWithCustomerLiabilityAirTrafficLiabilityLoyaltyProgramCustomerFundsExpiring100.0

luv:ContractWithCustomerLiabilityAirTrafficLiabilityServiceRevenue

luv:ContractWithCustomerLiabilityAirTrafficLiabilityServiceRevenue


Contract
Period End2021-06-302020-12-31
Value39602686
Percentage of ContractWithCustomerLiabilityAirTrafficLiabilityServiceRevenue100.0100.0

luv:ContractWithCustomerLiabilityCurrentCustomerTravelFunds

luv:ContractWithCustomerLiabilityCurrentCustomerTravelFunds


Contract
Period End2020-12-31
Value2100
Percentage of ContractWithCustomerLiabilityCurrentCustomerTravelFunds100.0

luv:DebtInstrumentFaceAmountNetOfFees us-gaap:DebtInstrument

luv:DebtInstrumentFaceAmountNetOfFees

luv:SecuredDebtBySixAircraft


Debt
Period End2020-12-31
Value190
Percentage of DebtInstrumentFaceAmountNetOfFees100.0

luv:DeferredSupplierPaymentsCurrent

luv:DeferredSupplierPaymentsCurrent


Deferred
Period End2021-06-30
Value151
Percentage of DeferredSupplierPaymentsCurrent100.0

luv:DeferredTaxAssetsConstructionObligation

luv:DeferredTaxAssetsConstructionObligation


Deferred
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value7238355326402289209168127
Percentage of DeferredTaxAssetsConstructionObligation100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:DeferredTaxAssetsOperatingLeaseLiability

luv:DeferredTaxAssetsOperatingLeaseLiability


Deferred
Period End2020-12-312019-12-31
Value443308
Percentage of DeferredTaxAssetsOperatingLeaseLiability100.0100.0

luv:DeferredTaxAssetsResidualTravelFunds

luv:DeferredTaxAssetsResidualTravelFunds


Deferred
Period End2020-12-31
Value117
Percentage of DeferredTaxAssetsResidualTravelFunds100.0

luv:DefinedBenefitPlanHealthCareCostTrendRateReachedIn2028

luv:DefinedBenefitPlanHealthCareCostTrendRateReachedIn2028


Defined
Period End2020-12-31
Value4.75
Percentage of DefinedBenefitPlanHealthCareCostTrendRateReachedIn2028100.0

luv:DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal

luv:DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value131907768604980120150953332751751368492771209.06.01.04.01386271183145306
Percentage of DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:OtherAssetsCurrent, us-gaap:CommodityContract


Derivative
Period End2020-12-312019-12-312018-12-312017-12-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value10.03843971.02.0130.00.02.0150.012664367503048
Percentage of DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal11.177.645.371.31.12.610.80.00.00.0166.70.014.024.423.546.20.00.015.7

us-gaap:OtherAssets, us-gaap:CommodityContract


Derivative
Period End2020-12-312019-12-312018-12-312017-12-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value90479513691771202.00.0157.00.072254165125589.0172221
Percentage of DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal100.095.9100.0100.098.9100.0100.00.00.00.077.80.083.793.790.286.20.00.00.072.2

us-gaap:OtherAssets, us-gaap:InterestRateSwap


Derivative
Period End2021-03-312020-06-302020-03-312019-12-312019-09-302018-12-312017-06-302016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value6.00.00.02.01.00.01.00.01321162.06.01.04.0131417182022222931
Percentage of DerivativeAssetFairValueAmountOffsetAgainstCollateralTotal4.60.00.04.11.20.01.10.00.00.00.022.2100.0100.0100.0100.016.36.39.813.80.00.00.010.1

luv:DerivativeAssetFairValueGrossLiabilityOffset us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:DerivativeAssetFairValueGrossLiabilityOffset

luv:OtherAssetsCurrent, us-gaap:CommodityContract


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value153.01.01.01.010.00.00.0150.01481288350641.02.048131928260.012240169182253101327
Percentage of DerivativeAssetFairValueGrossLiabilityOffset100.0100.0100.0100.0100.0100.00.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherAssets, us-gaap:CommodityContract


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value5731263119150.00.00.00.01732200.0153451589.011300.00.0871926910012038-232.0-367.0
Percentage of DerivativeAssetFairValueGrossLiabilityOffset380.01033.32600.03100.01900.0150.00.00.00.00.011.525.024.10.023.43400.02550.0120.869.257.9107.10.00.0725.080.040.854.947.437.60.0-112.2

luv:DerivativeAssetNoncurrentCollateralObligationToReturnCashOffset us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:DerivativeAssetNoncurrentCollateralObligationToReturnCashOffset

us-gaap:OtherAssets, us-gaap:CommodityContract


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-09-302018-06-302018-03-312017-12-31
Value5731263119151732200.0
Percentage of DerivativeAssetNoncurrentCollateralObligationToReturnCashOffset100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

luv:DerivativeLiabilityFairValueAmountOffsetAgainstCollateralTotal us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:DerivativeLiabilityFairValueAmountOffsetAgainstCollateralTotal

us-gaap:OtherNoncurrentLiabilities, us-gaap:InterestRateSwap


Derivative
Period End2020-12-312019-12-312018-12-312017-12-312017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302012-12-31
Value6.01.012212430353644464954546161374041455437
Percentage of DerivativeLiabilityFairValueAmountOffsetAgainstCollateralTotal100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:DerivativeLiabilityFairValueGrossAssetOffset us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:DerivativeLiabilityFairValueGrossAssetOffset

luv:OtherAssetsCurrent, us-gaap:CommodityContract


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302012-12-31
Value153.01.01.01.010.00.01481288350641.02.048131928260.012240169182253101327
Percentage of DerivativeLiabilityFairValueGrossAssetOffset100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherAssets, us-gaap:CommodityContract


Derivative
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-31
Value5731263119150.01732200.0153451589.011300.00.0871926910012038-232.0-367.0
Percentage of DerivativeLiabilityFairValueGrossAssetOffset380.01033.32600.03100.01900.0150.00.011.525.024.10.023.43400.02550.0120.869.257.9107.10.00.0725.080.040.854.947.437.60.0-112.2

luv:DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI

luv:DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI


Discontinuationof
Period End2021-06-302021-03-31
Value6062
Percentage of DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI100.0100.0

luv:DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI us-gaap:DerivativeInstrumentRisk, us-gaap:HedgingDesignation

us-gaap:InterestRateSwap, us-gaap:Nondesignated


Discontinuationof
Period End2020-09-302020-06-302020-03-31
Value141417
Percentage of DiscontinuationofInterestRateCashFlowHedgeBalanceinAOCI0.00.00.0

luv:EmergencyExtendedTimeOffTotalAccrued

luv:EmergencyExtendedTimeOffTotalAccrued


Emergency
Period End2020-09-30
Value588
Percentage of EmergencyExtendedTimeOffTotalAccrued100.0

luv:EmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020 us-gaap:UnusualOrInfrequentItem

luv:EmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020

luv:COVID19


Employees
Period End2021-06-302020-06-01
Value7000.011000.0
Percentage of EmployeesWhoParticipatedInExtendedEmergencyTimeOffDuring2020100.0100.0

luv:ExtendedEmergencyTimeOffAccruedLiability

luv:ExtendedEmergencyTimeOffAccruedLiability


Extended
Period End2021-06-302021-03-312020-12-312020-09-30
Value763190393457
Percentage of ExtendedEmergencyTimeOffAccruedLiability100.0100.0100.0100.0

luv:ExtendedEmergencyTimeOffOtherNoncurrentLiability

luv:ExtendedEmergencyTimeOffOtherNoncurrentLiability


Extended
Period End2020-12-312020-09-30
Value57131
Percentage of ExtendedEmergencyTimeOffOtherNoncurrentLiability100.0100.0

luv:FinanceLeaseRightofUseAssetAccumulatedDepreciation

luv:FinanceLeaseRightofUseAssetAccumulatedDepreciation


Finance
Period End2020-12-312019-12-31
Value567455
Percentage of FinanceLeaseRightofUseAssetAccumulatedDepreciation100.0100.0

luv:FuelPayable

luv:FuelPayable


Fuel
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value112986649685712912010611912210895107123139795795665449484668598599106100102112
Percentage of FuelPayable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived us-gaap:CounterpartyName, us-gaap:Range, us-gaap:DerivativeInstrumentRisk

luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived

luv:CounterpartyAlpha, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value0.00.00.00.00.00.00.05050505050
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived0.00.00.00.00.00.00.0100.0100.0100.0100.0100.0

luv:CounterpartyD, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value125125-125.0-125.0125125125125125125125125
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived0.00.00.00.00.00.00.0250.0250.0250.0250.0250.0

luv:CounterpartyE, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value100100100100100100100100-100.0-100.0100-100.0
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelInWhichCashIsReceived0.00.00.00.00.00.00.0200.0-200.0-200.0200.0-200.0

luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold1 us-gaap:CounterpartyName, us-gaap:Range, us-gaap:DerivativeInstrumentRisk

luv:InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold1

luv:CounterpartyAlpha, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-100000000.0-100000000.0-100000000.0-100000000.0-100000000.0-100000000.0-100000000.0-50000000.0-50000000.0-50000000.0-50000000.0-50000000.0
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

luv:CounterpartyE, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-40000000.0-40000000.0-40000000.0-40000000.0-40000000.0-40000000.0-40000000.0-40000000.0-40000000.0-125000000.0-125000000.0-125000000.0
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold140.040.040.040.040.040.040.080.080.0250.0250.0250.0

luv:CounterpartyF, srt:Minimum, us-gaap:CommodityContract


Investment
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-65000000.0-65000000.0-65000000.0-65000000.0-65000000.0-65000000.0-70000000.0-70000000.0-70000000.0-70000000.0-70000000.0
Percentage of InvestmentGradeRatingFairValueOfFuelDerivativeLevelsInWhichCashIsProvidedThreshold165.065.065.065.065.065.0140.0140.0140.0140.0140.0

luv:LeaseLiability

luv:LeaseLiability


Lease
Period End2020-12-312019-12-31
Value24101958
Percentage of LeaseLiability100.0100.0

luv:LeaseRightofUseAsset

luv:LeaseRightofUseAsset


Lease
Period End2020-12-312019-12-31
Value25592128
Percentage of LeaseRightofUseAsset100.0100.0

luv:LetterOfCreditPercentOfCollateral

luv:LetterOfCreditPercentOfCollateral


Letter
Period End2021-06-30
Value100.0
Percentage of LetterOfCreditPercentOfCollateral100.0

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalThereafter

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalThereafter


Longterm
Period End2020-09-30
Value4500
Percentage of LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalThereafter100.0

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalinYearSix

luv:LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalinYearSix


Longterm
Period End2020-09-30
Value4000
Percentage of LongtermDebtandCapitalLeaseObligationsMaturitiesRepaymentsofPrincipalinYearSix100.0

luv:MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther

luv:MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther


Maximum
Period End2021-06-302021-03-312020-12-312020-09-30
Value9000000.04000000.010000000.09000000.0
Percentage of MaximumSumOfDerivativesOfCounterpartyToBeIncludedInOther100.0100.0100.0100.0

luv:MunicipalBondsPrincipalRemaining luv:AirportProject

luv:MunicipalBondsPrincipalRemaining

luv:DAL


Municipal
Period End2020-12-312018-12-31
Value399416
Percentage of MunicipalBondsPrincipalRemaining100.0100.0

luv:NetPresentValueofPrincipalRemaining luv:AirportProject

luv:NetPresentValueofPrincipalRemaining

luv:DAL


Net
Period End2020-12-312019-12-31
Value433444
Percentage of NetPresentValueofPrincipalRemaining100.0100.0

luv:NetPresentValueofPrincipalRemaining us-gaap:OtherCommitments

luv:DAL


Net
Period End2021-06-302021-03-312020-09-30
Value432438448
Percentage of NetPresentValueofPrincipalRemaining0.00.00.0

luv:NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets us-gaap:StatementEquityComponents

luv:NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets

luv:OtherComprehensiveIncomeOtherChangesNetOfTax


New
Period End2021-03-31
Value-31.0
Percentage of NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets100.0

us-gaap:AccumulatedNetUnrealizedInvestmentGainLoss


New
Period End2021-03-31
Value12
Percentage of NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets-38.7

us-gaap:AccumulatedOtherComprehensiveIncome


New
Period End2021-03-312018-12-31
Value-19.00.0
Percentage of NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets61.30.0

us-gaap:AociIncludingPortionAttributableToNoncontrollingInterest


New
Period End2021-03-31
Value-19.0
Percentage of NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets61.3

us-gaap:RetainedEarnings


New
Period End2021-03-312018-12-31
Value1955
Percentage of NewAccountingPronouncementOrChangeInAccountingPrincipleCumulativeEffectOfChangeOnEquityOrNetAssets-61.30.0

luv:NumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12ToBeDeliveredIn2022

luv:NumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12ToBeDeliveredIn2022


Number
Period End2021-03-31
Value30.0
Percentage of NumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12ToBeDeliveredIn2022100.0

luv:OperatingLeasesFutureMinimumPaymentsDueThereafterYear6 us-gaap:SaleLeasebackTransactionDescription

luv:OperatingLeasesFutureMinimumPaymentsDueThereafterYear6

luv:A2Q20SaleleasebackOf10737800And10737MAX8Aircraft


Operating
Period End2020-09-30
Value440
Percentage of OperatingLeasesFutureMinimumPaymentsDueThereafterYear6100.0

luv:OperatingLeasesFutureMinimumPaymentsDueinSixYears us-gaap:SaleLeasebackTransactionDescription

luv:OperatingLeasesFutureMinimumPaymentsDueinSixYears

luv:A2Q20SaleleasebackOf10737800And10737MAX8Aircraft


Operating
Period End2020-09-30
Value71
Percentage of OperatingLeasesFutureMinimumPaymentsDueinSixYears100.0

luv:Outstandingremainingguaranteedobligation us-gaap:OtherCommitments

luv:Outstandingremainingguaranteedobligation

luv:LosAngelesWorldAirportTerminal1.5


Outstandingremainingguaranteedobligationus-gaap:
Period End2020-09-302019-03-312018-09-30
Value28912583
Percentage of Outstandingremainingguaranteedobligation100.0100.0100.0

luv:PercentageOfEmployeesRepresentedByUnionsUnderCollectiveBargainingAgreementsInNegotiations

luv:PercentageOfEmployeesRepresentedByUnionsUnderCollectiveBargainingAgreementsInNegotiations


Percentage
Period End2020-12-31
Value55.0
Percentage of PercentageOfEmployeesRepresentedByUnionsUnderCollectiveBargainingAgreementsInNegotiations100.0

luv:PrincipalRemaining us-gaap:OtherCommitments

luv:PrincipalRemaining

luv:DAL


Principal
Period End2021-03-312020-09-30
Value399407
Percentage of PrincipalRemaining100.0100.0

luv:ProceedsFromPSP3PayrollSupportProgramGrantPerAmericanRescuePlanActOf2021ReceivedinApril2021 us-gaap:SubsequentEventType

luv:ProceedsFromPSP3PayrollSupportProgramGrantPerAmericanRescuePlanActOf2021ReceivedinApril2021

us-gaap:SubsequentEvent


Proceeds
Period End2021-04-23
Value926
Percentage of ProceedsFromPSP3PayrollSupportProgramGrantPerAmericanRescuePlanActOf2021ReceivedinApril2021100.0

luv:ProceedsFromPSP3PayrollSupportProgramPerAmericanRescuePlanActOf2021 us-gaap:SubsequentEventType

luv:ProceedsFromPSP3PayrollSupportProgramPerAmericanRescuePlanActOf2021

us-gaap:SubsequentEvent


Proceeds
Period End2021-04-23
Value1900
Percentage of ProceedsFromPSP3PayrollSupportProgramPerAmericanRescuePlanActOf2021100.0

luv:ProceedsFromPayrollSupportProgram

luv:ProceedsFromPayrollSupportProgram


Proceeds
Period End2021-03-31
Value3400
Percentage of ProceedsFromPayrollSupportProgram100.0

luv:ProceedsFromPayrollSupportProgramExtensionDuringFirstQuarter2021

luv:ProceedsFromPayrollSupportProgramExtensionDuringFirstQuarter2021


Proceeds
Period End2021-03-31
Value1700
Percentage of ProceedsFromPayrollSupportProgramExtensionDuringFirstQuarter2021100.0

luv:ProceedsFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsActThatWillBeUsedToOffsetSalariesWagesAndBenefitsExpensesIn1Q21

luv:ProceedsFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsActThatWillBeUsedToOffsetSalariesWagesAndBenefitsExpensesIn1Q21


Proceeds
Period End2020-12-31
Value1700
Percentage of ProceedsFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsActThatWillBeUsedToOffsetSalariesWagesAndBenefitsExpensesIn1Q21100.0

luv:ProceedsFromPayrollSupportProgramExtensionGrantReceivedInJanuary2021 us-gaap:SubsequentEventType

luv:ProceedsFromPayrollSupportProgramExtensionGrantReceivedInJanuary2021

us-gaap:SubsequentEvent


Proceeds
Period End2021-01-15
Value864
Percentage of ProceedsFromPayrollSupportProgramExtensionGrantReceivedInJanuary2021100.0

luv:ProceedsFromPayrollSupportProgramExtensionReceivedInApril2021 luv:PayrollSupportProgramAgreement, us-gaap:SubsequentEventType

luv:ProceedsFromPayrollSupportProgramExtensionReceivedInApril2021

luv:PSP2PayrollSupportProgramExtensionTopoffReceivedApril232021, us-gaap:SubsequentEvent


Proceeds
Period End2021-04-23
Value259
Percentage of ProceedsFromPayrollSupportProgramExtensionReceivedInApril2021100.0

luv:ProceedsFromPayrollSupportProgramGrantReceivedInJuly2020

luv:ProceedsFromPayrollSupportProgramGrantReceivedInJuly2020


Proceeds
Period End2020-07-30
Value326
Percentage of ProceedsFromPayrollSupportProgramGrantReceivedInJuly2020100.0

luv:ProceedsFromPayrollSupportProgramGrantReceivedInSeptember2020

luv:ProceedsFromPayrollSupportProgramGrantReceivedInSeptember2020


Proceeds
Period End2020-09-30
Value94
Percentage of ProceedsFromPayrollSupportProgramGrantReceivedInSeptember2020100.0

luv:ProceedsFromPayrollSupportProgramGrantRemainingToBeAllocatedToPayrollSupportVoluntarySeparationNet

luv:ProceedsFromPayrollSupportProgramGrantRemainingToBeAllocatedToPayrollSupportVoluntarySeparationNet


Proceeds
Period End2021-06-302020-12-312020-06-302019-12-31
Value483939570.0
Percentage of ProceedsFromPayrollSupportProgramGrantRemainingToBeAllocatedToPayrollSupportVoluntarySeparationNet100.0100.0100.00.0

luv:RequiredMinimumLiquidityLevelatAllTimesAfterMarch312021

luv:RequiredMinimumLiquidityLevelatAllTimesAfterMarch312021


Required
Period End2020-12-312020-09-30
Value15002500
Percentage of RequiredMinimumLiquidityLevelatAllTimesAfterMarch312021100.0100.0

luv:ResidualTravelFunds

luv:ResidualTravelFunds


Residual
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-31
Value15.022.028.027.00.280.330.13
Percentage of ResidualTravelFunds100.0100.0100.0100.0100.0100.0100.0

luv:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAveragePrice us-gaap:AwardType

luv:ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAveragePrice

us-gaap:StockCompensationPlan


Share
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-31
Value29.652.0153.0157.0442.941.2724.91
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWeightedAveragePrice100.0100.0100.0100.0100.0100.0100.0

luv:TerminatedInterestRateSwapLiability

luv:TerminatedInterestRateSwapLiability


Terminated
Period End2020-09-30
Value28
Percentage of TerminatedInterestRateSwapLiability100.0

luv:TotalCapitalCommitmentsShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020

luv:TotalCapitalCommitmentsShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020


Total
Period End2020-12-31
Value2100
Percentage of TotalCapitalCommitmentsShiftingIntoFuturePeriodsAssociatedWithContractualObligationsThatDidNotTakePlaceIn2019Or2020100.0

luv:TotalCollateralAlreadyPostedAggregateFairValue us-gaap:DerivativeInstrumentRisk

luv:TotalCollateralAlreadyPostedAggregateFairValue

us-gaap:CommodityContract


Total
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312014-03-312013-12-312013-06-302012-12-31
Value34-25.00.0-15.03018352660.00.0650.0
Percentage of TotalCollateralAlreadyPostedAggregateFairValue100.0100.00.0100.0100.0100.0100.00.00.0100.00.0

luv:TotalCollateralAlreadyReceivedAggregateFairValue us-gaap:BalanceSheetLocation, us-gaap:DerivativeInstrumentRisk

luv:TotalCollateralAlreadyReceivedAggregateFairValue

luv:OtherAssetsCurrent, us-gaap:CommodityContract


Total
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-06-302014-03-312013-12-31
Value3.010.00.0153.01.02.04.06.09.09.00.02310.00.0
Percentage of TotalCollateralAlreadyReceivedAggregateFairValue100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0

us-gaap:OtherAssets, us-gaap:CommodityContract


Total
Period End2020-12-312019-12-312018-12-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-06-302013-12-31
Value31150.00.01.01.05.06.09.0114.00.0820.0
Percentage of TotalCollateralAlreadyReceivedAggregateFairValue1033.3150.00.00.033.3100.0250.0150.0150.0122.244.40.0356.50.0

luv:TotalNotToExceedCostOfAirportProject us-gaap:OtherCommitments

luv:TotalNotToExceedCostOfAirportProject

luv:LosAngelesWorldAirportTerminal15


Total
Period End2021-06-30
Value410
Percentage of TotalNotToExceedCostOfAirportProject100.0

luv:TotalNumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12

luv:TotalNumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12


Total
Period End2021-03-31
Value100.0
Percentage of TotalNumberOfBoeing737MAX7FirmOrdersAddedToPurchaseAgreementPerSupplementalAgreementNo12100.0

luv:TotalNumberOfBoeing737MAX8FirmOrdersConvertedTo737MAX7FirmOrdersPerSupplementalAgreementNo12

luv:TotalNumberOfBoeing737MAX8FirmOrdersConvertedTo737MAX7FirmOrdersPerSupplementalAgreementNo12


Total
Period End2021-03-31
Value70.0
Percentage of TotalNumberOfBoeing737MAX8FirmOrdersConvertedTo737MAX7FirmOrdersPerSupplementalAgreementNo12100.0

luv:TotalNumberOfBoeing737MAXOptionsAddedToPurchaseAgreementPerSupplementalAgreementNo12

luv:TotalNumberOfBoeing737MAXOptionsAddedToPurchaseAgreementPerSupplementalAgreementNo12


Total
Period End2021-03-31
Value155.0
Percentage of TotalNumberOfBoeing737MAXOptionsAddedToPurchaseAgreementPerSupplementalAgreementNo12100.0

luv:TotalProceedsFromPayrollSupportProgramExtensionPSP2 luv:PayrollSupportProgramAgreement, us-gaap:SubsequentEventType

luv:TotalProceedsFromPayrollSupportProgramExtensionPSP2

luv:TotalAmountOfPSP2PayrollSupportProgramExtensionAgreement, us-gaap:SubsequentEvent


Total
Period End2021-04-23
Value2000
Percentage of TotalProceedsFromPayrollSupportProgramExtensionPSP2100.0

luv:TotalProceedsToBeProvidedToUSAirlinesFromPSP3PayrollSupportPerAmericanRescuePlanActOf2021

luv:TotalProceedsToBeProvidedToUSAirlinesFromPSP3PayrollSupportPerAmericanRescuePlanActOf2021


Total
Period End2021-03-11
Value14000
Percentage of TotalProceedsToBeProvidedToUSAirlinesFromPSP3PayrollSupportPerAmericanRescuePlanActOf2021100.0

luv:TotalProceedsToBeProvidedToUSAirlinesFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsAct

luv:TotalProceedsToBeProvidedToUSAirlinesFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsAct


Total
Period End2020-12-27
Value15000
Percentage of TotalProceedsToBeProvidedToUSAirlinesFromPayrollSupportProgramExtensionGrantOfConsolidatedAppropriationsAct100.0

luv:TradeReceivables

luv:TradeReceivables


Trade
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312018-12-31
Value59464846445357
Percentage of TradeReceivables100.0100.0100.0100.0100.0100.0100.0

luv:UnsecuredTermLoanToBeIssuedThroughPayrollSupportProgramExtensionOfConsolidatedAppropriationsAct

luv:UnsecuredTermLoanToBeIssuedThroughPayrollSupportProgramExtensionOfConsolidatedAppropriationsAct


Unsecured
Period End2020-12-31
Value259
Percentage of UnsecuredTermLoanToBeIssuedThroughPayrollSupportProgramExtensionOfConsolidatedAppropriationsAct100.0

luv:VendorPrepayment

luv:VendorPrepayment


Vendor
Period End2021-03-312020-12-31
Value277600
Percentage of VendorPrepayment100.0100.0

luv:VoluntarySeparationProgram2020AccruedLiability

luv:VoluntarySeparationProgram2020AccruedLiability


Voluntary
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302019-12-31
Value1121241432423070.0
Percentage of VoluntarySeparationProgram2020AccruedLiability100.0100.0100.0100.0100.00.0

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffTotalAccrued

luv:VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffTotalAccrued


Voluntary
Period End2021-03-312020-12-312020-09-302020-06-30
Value6119141207307
Percentage of VoluntarySeparationProgram2020AndExtendedEmergencyTimeOffTotalAccrued100.0100.0100.0100.0

luv:VoluntarySeparationProgram2020OtherNoncurrentLiability

luv:VoluntarySeparationProgram2020OtherNoncurrentLiability


Voluntary
Period End2021-06-302021-03-312020-12-312020-09-30
Value276297321377
Percentage of VoluntarySeparationProgram2020OtherNoncurrentLiability100.0100.0100.0100.0

luv:VoluntarySeparationProgram2020Participants luv:Workgroup

luv:VoluntarySeparationProgram2020Participants

luv:ManagerialAndAdministrative


Voluntary
Period End2020-12-312020-09-302020-06-30
Value1140.01140.01145.0
Percentage of VoluntarySeparationProgram2020Participants100.0100.0100.0

luv:Pilots


Voluntary
Period End2020-12-312020-09-302020-06-30
Value630.0630.0640.0
Percentage of VoluntarySeparationProgram2020Participants55.355.355.9

luv:VoluntarySeparationProgram2020Participants us-gaap:UnusualOrInfrequentItem

luv:COVID19


Voluntary
Period End2021-06-30
Value4200.0
Percentage of VoluntarySeparationProgram2020Participants0.0

luv:VoluntarySeparationProgram2020TotalAccrued

luv:VoluntarySeparationProgram2020TotalAccrued


Voluntary
Period End2020-09-302020-06-30
Value619307
Percentage of VoluntarySeparationProgram2020TotalAccrued100.0100.0

luv:WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan

luv:WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan


Weighted
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
Value34.3947.650.7350.1336.5736.423.1712.038.019.7311.256.7811.29
Percentage of WeightedAverageFairValueOfStockPurchaseRightUnderEmployeeStockPurchasePlan100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsAndOtherReceivablesNetCurrent

us-gaap:AccountsAndOtherReceivablesNetCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-31
Value132893711308977707091086867777784568784765680662579576585546848524511474465462499365468447457419463514429332430502367299
Percentage of AccountsAndOtherReceivablesNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsPayableOtherCurrent

us-gaap:AccountsPayableOtherCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value453357409440389320521388416466526406417412569432473462535468425421442360331345358303272308323246
Percentage of AccountsPayableOtherCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccountsPayableTradeCurrent

us-gaap:AccountsPayableTradeCurrent


Accounts
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value219169111169139218304270260256263266280189186165171181138148227191178170170181123189221187189174
Percentage of AccountsPayableTradeCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccrualForTaxesOtherThanIncomeTaxesCurrent

us-gaap:AccrualForTaxesOtherThanIncomeTaxesCurrent


Accrual
Period End2020-12-312019-12-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-31
Value84797316568617256577913414568631402326212912120081506562
Percentage of AccrualForTaxesOtherThanIncomeTaxesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccruedEmployeeBenefitsCurrent

us-gaap:AccruedEmployeeBenefitsCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312010-12-31
Value109109111110104991201181109610796979510093969096908880867771728470727173626162706060565643
Percentage of AccruedEmployeeBenefitsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccruedSalariesCurrent

us-gaap:AccruedSalariesCurrent


Accrued
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312012-12-31
Value253197201184207226231199205213216183215202201175197203200149174171173340168161160142157150156148
Percentage of AccruedSalariesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AccruedVacationCurrent

us-gaap:AccruedVacationCurrent


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
Value4484434364184544434344274214134033923833723653483393343553393173143093103022972922912872822782862812752702632582532480.0002390.000235203200190
Percentage of AccruedVacationCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AirlineRelatedInventory

us-gaap:AirlineRelatedInventory


Airline
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value4644484144264225185295285104844614834594304204383653563373313282893113083263043424294354384675214614804695444464324010.0004590.000394320243
Percentage of AirlineRelatedInventory100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

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

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value161681364012722138651382950733392345135793321310133252731
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value967954871925849658879744579702715636649
Percentage of AssetsFairValueDisclosure6.07.06.86.76.113.025.921.616.221.123.119.123.8

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value50224913410910785110114187254138698283
Percentage of AssetsFairValueDisclosure3.11.81.10.80.81.73.23.35.27.64.521.010.4

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency

us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value1484313727148991478558164381430943454277395446593663
Percentage of AssetsFairValueDisclosure108.8107.9107.5106.9114.6129.2124.9121.4128.8127.5140.1134.1

us-gaap:AssetsFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


Assets
Period End2021-06-302020-12-31
Value1763713727
Percentage of AssetsFairValueDisclosure109.1107.9

us-gaap:CapitalizedComputerSoftwareNet

us-gaap:CapitalizedComputerSoftwareNet


Capitalized
Period End2020-12-312019-12-312018-12-312017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value697630674654544378403357256
Percentage of CapitalizedComputerSoftwareNet100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:CashAndCashEquivalents, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:BankTimeDeposits, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-06-302020-12-31
Value275300
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0

us-gaap:CashEquivalents, us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-06-302020-12-31
Value1375910663
Percentage of CashAndCashEquivalentsFairValueDisclosure5003.33554.3

us-gaap:CertificatesOfDeposit, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2020-12-31
Value10.0
Percentage of CashAndCashEquivalentsFairValueDisclosure3.3

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:CashAndCashEquivalents, us-gaap:FairValueByMeasurementFrequency

us-gaap:BankTimeDeposits, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-06-302020-12-31
Value275300
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0

us-gaap:CashEquivalents, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-06-302020-12-31
Value1375910663
Percentage of CashAndCashEquivalentsFairValueDisclosure5003.33554.3

us-gaap:CertificatesOfDeposit, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2020-12-31
Value10.0
Percentage of CashAndCashEquivalentsFairValueDisclosure3.3

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByAssetClass, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:BankTimeDeposits, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312018-09-30
Value2753001252816625252525
Percentage of CashAndCashEquivalentsFairValueDisclosure0.0100.00.00.00.00.00.00.00.0

us-gaap:CashEquivalents, us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value1160010663118371196134951999207821161870139216961133134413371110992829
Percentage of CashAndCashEquivalentsFairValueDisclosure0.03554.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CertificatesOfDeposit, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value6.010.0121919145.010.09.08.0141211134.02334
Percentage of CashAndCashEquivalentsFairValueDisclosure0.03.30.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommercialPaper, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-312014-12-312013-12-312012-12-31
Value90901359036053540529544045436935032520070280170
Percentage of CashAndCashEquivalentsFairValueDisclosure0.030.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByAssetClass, us-gaap:FairValueByMeasurementBasis, us-gaap:FairValueByMeasurementFrequency

us-gaap:BankTimeDeposits, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-06-302019-03-312018-12-312018-09-30
Value2753001252816625252525
Percentage of CashAndCashEquivalentsFairValueDisclosure0.0100.00.00.00.00.00.00.00.0

us-gaap:CashEquivalents, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-31
Value116001066311837119613495199920782116187013921696113313441337
Percentage of CashAndCashEquivalentsFairValueDisclosure0.03554.30.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CertificatesOfDeposit, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-31
Value6.010.0121919145.010.09.08.014121113
Percentage of CashAndCashEquivalentsFairValueDisclosure0.03.30.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommercialPaper, us-gaap:EstimateOfFairValueFairValueDisclosure, us-gaap:FairValueMeasurementsRecurring


Cash
Period End2021-03-312020-12-312020-09-302020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312016-12-312015-12-31
Value909013590360535405295440454369350325200
Percentage of CashAndCashEquivalentsFairValueDisclosure0.030.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1

luv:TotalAmountOfPSP2PayrollSupportProgramExtensionAgreement, luv:LUVCommonStockWarrants


Class
Period End2021-03-31
Value46.28
Percentage of ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1100.0

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType

luv:PSP3PayrollSupportProgramAgreement, us-gaap:CommonStock, us-gaap:SubsequentEvent


Class
Period End2021-04-23
Value58.51
Percentage of ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights10.0

us-gaap:ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

luv:UnitedStatesDepartmentOfTreasury, luv:AmericanRescuePlanActOf2021


Class
Period End2021-06-30
Value58.51
Percentage of ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights10.0

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Class
Period End2021-06-30
Value46.28
Percentage of ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights10.0

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights us-gaap:CounterpartyName, us-gaap:UnusualOrInfrequentItem

us-gaap:ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights

luv:UnitedStatesDepartmentOfTreasury, luv:ConsolidatedAppropriationsAct2021


Class
Period End2021-06-30
Value1200000.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights100.0

luv:UnitedStatesDepartmentOfTreasury, luv:CoronavirusAidReliefAndEconomicSecurityAct


Class
Period End2020-12-31
Value2700000.0
Percentage of ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights0.0

us-gaap:ClassOfWarrantOrRightOutstanding

us-gaap:ClassOfWarrantOrRightOutstanding


Class
Period End2020-12-31
Value2700000.0
Percentage of ClassOfWarrantOrRightOutstanding100.0

us-gaap:ClassOfWarrantOrRightOutstanding luv:PayrollSupportProgramAgreement, us-gaap:ClassOfWarrantOrRight, us-gaap:SubsequentEventType

luv:PSP2PayrollSupportProgramExtensionTopoffReceivedApril232021, luv:LUVCommonStockWarrants, us-gaap:SubsequentEvent


Class
Period End2021-04-23
Value168000.0
Percentage of ClassOfWarrantOrRightOutstanding0.0

luv:PSP3PayrollSupportProgramAgreement, luv:LUVCommonStockWarrants, us-gaap:SubsequentEvent