XML 12 R39.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Fair Value Measurements - Measured on Recurring Basis (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2015 | Dec. 31, 2012 | Dec. 31, 2014
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | $ 1,244 us-gaap_DerivativeFairValueOfDerivativeAsset | [1] |  | $ 1,360 us-gaap_DerivativeFairValueOfDerivativeAsset | [1]
Fuel derivatives: |  |  |  |  |
Derivative Liability, Fair Value, Gross Liability | (2,367)us-gaap_DerivativeFairValueOfDerivativeLiability | [1] |  | (2,409)us-gaap_DerivativeFairValueOfDerivativeLiability | [1]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount | 0 us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount |  |  | 0 us-gaap_FairValueAssetsLevel1ToLevel2TransfersAmount |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount | 0 us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount |  |  | 0 us-gaap_FairValueLiabilitiesLevel1ToLevel2TransfersAmount |
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount | 0 us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount |  |  | 0 us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount | 0 us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount |  |  | 0 us-gaap_FairValueLiabilitiesLevel2ToLevel1TransfersAmount |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet |  | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Transfers, Net | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet |  | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityTransfersNet |  |
Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Treasury bills | 1,150 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 1,450 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Interest rate derivatives | 4 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 13 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Other available for sale securities | 61 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 68 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total assets | 4,770 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 4,443 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Liabilities |  |  |  |  |
Interest rate derivatives | (61)us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | (61)us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total Liabilities | (2,367)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | (2,409)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Treasury bills | 1,150 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 1,450 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Interest rate derivatives | 0 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Other available for sale securities | 61 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 63 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total assets | 3,102 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 2,623 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Liabilities |  |  |  |  |
Interest rate derivatives | 0 us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total Liabilities | 0 us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Treasury bills | 0 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Interest rate derivatives | 4 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 13 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Other available for sale securities | 0 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total assets | 916 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 896 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Liabilities |  |  |  |  |
Interest rate derivatives | (61)us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | (61)us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total Liabilities | (397)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | (426)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Treasury bills | 0 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Interest rate derivatives | 0 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InterestRateDerivativeAssetsAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Other available for sale securities | 0 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 5 us-gaap_OtherAssetsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total assets | 752 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 924 us-gaap_AssetsFairValueDisclosureRecurring / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Liabilities |  |  |  |  |
Interest rate derivatives | 0 us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InterestRateDerivativeLiabilitiesAtFairValue / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Total Liabilities | (1,970)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | (1,983)us-gaap_LiabilitiesFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Cash Equivalents | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 1,891 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2] |  | 1,110 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2]
Cash Equivalents | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 1,891 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2] |  | 1,110 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2]
Cash Equivalents | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2] |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2]
Cash Equivalents | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2] |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CashEquivalentsMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [2]
Commercial paper | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents |  |  |  | 70 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Commercial paper | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents |  |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Commercial paper | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents |  |  |  | 70 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Commercial paper | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents |  |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CommercialPaperMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 18 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 4 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 18 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 4 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_CertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Eurodollar time deposits | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 116 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 98 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Eurodollar time deposits | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Eurodollar time deposits | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 116 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 98 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Eurodollar time deposits | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Cash equivalents | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_CashAndCashEquivalentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_EuroDollarCertificatesOfDepositMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Investments | 263 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 256 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Investments | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Investments | 263 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 256 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Certificates of deposit | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Investments | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |  |  | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = luv_CertificatesOfDepositCurrentMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember |
Auction rate securities | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Assets |  |  |  |  |
Investments | 27 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] |  | 27 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3]
Auction rate securities | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Assets |  |  |  |  |
Investments | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] |  | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3]
Auction rate securities | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Assets |  |  |  |  |
Investments | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] |  | 0 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3]
Auction rate securities | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Assets |  |  |  |  |
Investments | 27 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3] |  | 27 us-gaap_InvestmentsFairValueDisclosure / luv_FairValueByFairValueAssetDescriptionAxis = us-gaap_AuctionRateSecuritiesMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [3]
Swap | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Fuel derivatives: |  |  |  |  |
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Fuel derivatives: |  |  |  |  |
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Swap | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
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Fuel derivatives: |  |  |  |  |
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Swap | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 515 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 455 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | (336)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | (365)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Swap | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
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Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_SwapMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Options Held | Fair Value, Measurements, Recurring | Period end date |  |  |  |  |
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 725 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 892 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | (1,970)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | (1,983)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_EstimateOfFairValueFairValueDisclosureMember / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Options Held | Fair Value, Measurements, Recurring | Quoted prices in active markets for identical assets (Level 1) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Options Held | Fair Value, Measurements, Recurring | Significant other observable inputs (Level 2) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 0 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 0 us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Options Held | Fair Value, Measurements, Recurring | Significant unobservable inputs (Level 3) |  |  |  |  |
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Asset | 725 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | 892 us-gaap_DerivativeFairValueOfDerivativeAsset / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
Fuel derivatives: |  |  |  |  |
Derivative Asset, Fair Value, Gross Liability | $ (1,970)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4] |  | $ (1,983)us-gaap_DerivativeAssetFairValueGrossLiability / us-gaap_DerivativeByNatureAxis = us-gaap_OptionMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member / us-gaap_FairValueByMeasurementFrequencyAxis = us-gaap_FairValueMeasurementsRecurringMember | [4]
[1] | Represents the position of each trade before consideration of offsetting positions with each counterparty and does not include the impact of cash collateral deposits provided to or received from counterparties. See discussion of credit risk and collateral following in this Note.
[2] | Cash equivalents are primarily composed of money market investments.
[3] | Noncurrent investments are included in Other assets in the unaudited Condensed Consolidated Balance Sheet.
[4] | In the unaudited Condensed Consolidated Balance Sheet amounts are presented as a net liability.

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