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Leases (Details) (USD $) | 3 Months Ended | 12 Months Ended | 3 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2013 CapitalLeases aircraft | Dec. 31, 2014 CapitalLeases aircraft | Dec. 31, 2013 CapitalLeases aircraft | Dec. 31, 2012 | Dec. 31, 2014 aircraft | Jun. 30, 2014 | Sep. 30, 2012 | Jul. 09, 2012 aircraft
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract] |  |  |  |  |  |  |  |  |  |
Flight equipment | $ 69,000,000 us-gaap_CapitalLeasedAssetsGross | $ 214,000,000 us-gaap_CapitalLeasedAssetsGross |  | $ 69,000,000 us-gaap_CapitalLeasedAssetsGross |  |  | $ 214,000,000 us-gaap_CapitalLeasedAssetsGross |  |  |
Less: accumulated amortization | 12,000,000 us-gaap_CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation | 22,000,000 us-gaap_CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation |  | 12,000,000 us-gaap_CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation |  |  | 22,000,000 us-gaap_CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation |  |  |
Total | 57,000,000 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet | 192,000,000 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet |  | 57,000,000 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet |  |  | 192,000,000 us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet |  |  |
Capital leases |  |  |  |  |  |  |  |  |  |
2015 |  | 33,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent |  |  |  |  | 33,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueCurrent |  |  |
2016 |  | 42,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears |  |  |  |  | 42,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInTwoYears |  |  |
2017 |  | 45,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears |  |  |  |  | 45,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInThreeYears |  |  |
2018 |  | 44,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears |  |  |  |  | 44,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFourYears |  |  |
2019 |  | 43,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears |  |  |  |  | 43,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueInFiveYears |  |  |
Thereafter |  | 202,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter |  |  |  |  | 202,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDueThereafter |  |  |
Total minimum lease payments |  | 409,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDue |  |  |  |  | 409,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsDue |  |  |
Less amount representing interest |  | 75,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments |  |  |  |  | 75,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments |  |  |
Present value of minimum lease payments |  | 334,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments |  |  |  |  | 334,000,000 us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments |  |  |
Less current portion |  | 23,000,000 us-gaap_CapitalLeaseObligationsCurrent |  |  |  |  | 23,000,000 us-gaap_CapitalLeaseObligationsCurrent |  |  |
Long-term portion |  | 311,000,000 us-gaap_CapitalLeaseObligationsNoncurrent |  |  |  |  | 311,000,000 us-gaap_CapitalLeaseObligationsNoncurrent |  |  |
Facility Operating leases |  |  |  |  |  |  |  |  |  |
2015 |  | 753,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent |  |  |  |  | 753,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent |  |  |
2016 |  | 715,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears |  |  |  |  | 715,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears |  |  |
2017 |  | 671,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears |  |  |  |  | 671,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears |  |  |
2018 |  | 573,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears |  |  |  |  | 573,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears |  |  |
2019 |  | 502,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears |  |  |  |  | 502,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears |  |  |
Thereafter |  | 1,802,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter |  |  |  |  | 1,802,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter |  |  |
Total minimum lease payments |  | 5,016,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDue |  |  |  |  | 5,016,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDue |  |  |
Subleases |  |  |  |  |  |  |  |  |  |
2015 |  | (93,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableCurrent |  |  |  |  | (93,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableCurrent |  |  |
2016 |  | (103,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears |  |  |  |  | (103,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears |  |  |
2017 |  | (103,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears |  |  |  |  | (103,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears |  |  |
2018 |  | (102,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInFourYears |  |  |  |  | (102,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInFourYears |  |  |
2019 |  | (97,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears |  |  |  |  | (97,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears |  |  |
Thereafter |  | (144,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableThereafter |  |  |  |  | (144,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableThereafter |  |  |
Total minimum lease payments |  | (642,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivable |  |  |  |  | (642,000,000)us-gaap_OperatingLeasesFutureMinimumPaymentsReceivable |  |  |
Operating leases, net |  |  |  |  |  |  |  |  |  |
2015 |  | 684,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetCurrent |  |  |  |  | 684,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetCurrent |  |  |
2016 |  | 636,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInTwoYears |  |  |  |  | 636,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInTwoYears |  |  |
2017 |  | 592,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInThreeYears |  |  |  |  | 592,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInThreeYears |  |  |
2018 |  | 496,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInFourYears |  |  |  |  | 496,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInFourYears |  |  |
2019 |  | 430,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInFiveYears |  |  |  |  | 430,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetInFiveYears |  |  |
Thereafter |  | 2,317,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetThereafter |  |  |  |  | 2,317,000,000 luv_OperatingLeasesFutureMinimumPaymentsNetThereafter |  |  |
Total minimum lease payments |  | 5,155,000,000 luv_OperatingLeasesFutureMinimumPaymentsNet |  |  |  |  | 5,155,000,000 luv_OperatingLeasesFutureMinimumPaymentsNet |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Number of capital leased assets | 4 us-gaap_CapitalLeasedAssetsNumberOfUnits | 16 us-gaap_CapitalLeasedAssetsNumberOfUnits |  | 4 us-gaap_CapitalLeasedAssetsNumberOfUnits |  |  | 16 us-gaap_CapitalLeasedAssetsNumberOfUnits |  |  |
Rental expense for operating leases |  | 931,000,000 us-gaap_LeaseAndRentalExpense |  | 997,000,000 us-gaap_LeaseAndRentalExpense |  | 943,000,000 us-gaap_LeaseAndRentalExpense |  |  |  |
Number of operating leased assets |  | 174 us-gaap_PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits |  |  |  |  | 174 us-gaap_PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits |  |  |
Number of aircraft sold in sale and leaseback transaction | 2 luv_NumberOfAircraftSoldInSaleAndLeasebackTransaction |  |  | 2 luv_NumberOfAircraftSoldInSaleAndLeasebackTransaction |  |  |  |  |  |
Sales Leaseback Transaction Gross Proceeds | 12,000,000 luv_SalesLeasebackTransactionGrossProceeds |  |  |  |  |  |  |  |  |
Leaseback Period | 11 years |  |  |  |  |  |  |  |  |
Number of aircraft expected to be converted to sublease per month |  | 3 luv_NumberofAircraftExpectedToBeConvertedtoSubleasePerMonth |  |  |  |  | 3 luv_NumberofAircraftExpectedToBeConvertedtoSubleasePerMonth |  |  |
Minimum |  |  |  |  |  |  |  |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Renewal term |  | 1 year |  |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Renewal term |  | 5 years |  |  |  |  |  |  |  |
B-717-200 |  |  |  |  |  |  |  |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Number of capital leased assets |  |  |  |  |  |  |  |  |  | 2 us-gaap_CapitalLeasedAssetsNumberOfUnits / us-gaap_AircraftTypeAxis = us-gaap_B717200Member
Number of operating leased assets |  |  |  |  |  |  |  |  |  | 76 us-gaap_PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits / us-gaap_AircraftTypeAxis = us-gaap_B717200Member
Number of aircrafts subleased |  |  |  |  |  |  |  |  |  | 88 luv_PropertySubjectToOrAvailableForLeaseNumberOfUnitsTotal / us-gaap_AircraftTypeAxis = us-gaap_B717200Member
Number of aircraft delivered to sublessee |  | 52 luv_NumberOfAircraftDeliveredToSublessee / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  | 52 luv_NumberOfAircraftDeliveredToSublessee / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |
Number of owned assets |  |  |  |  |  |  |  |  |  | 10 luv_OwnedAssetsNumberOfUnits / us-gaap_AircraftTypeAxis = us-gaap_B717200Member
Lease terms for owned aircraft |  |  |  |  |  |  | 7 years |  |  |
Contingent rental payment due |  | 0 us-gaap_CapitalLeasesContingentRentalPaymentsDue / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  | 0 us-gaap_CapitalLeasesContingentRentalPaymentsDue / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |
Residual value of leased properties |  | 0 us-gaap_CapitalLeasesNetInvestmentInSalesTypeLeasesUnguaranteedResidualValuesOfLeasedProperty / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  | 0 us-gaap_CapitalLeasesNetInvestmentInSalesTypeLeasesUnguaranteedResidualValuesOfLeasedProperty / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |
Estimated Loss On Sublease |  |  |  |  |  |  |  |  | 137,000,000 luv_EstimatedLossOnSublease / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |
Sublease transaction costs |  | 86,000,000 luv_SubleaseTransactionCosts / us-gaap_AircraftTypeAxis = us-gaap_B717200Member | [1] | 12,000,000 luv_SubleaseTransactionCosts / us-gaap_AircraftTypeAxis = us-gaap_B717200Member | [1] |  |  |  |  |
Sublease Obligations | 122,000,000 luv_SubleaseObligations / us-gaap_AircraftTypeAxis = us-gaap_B717200Member | 63,000,000 luv_SubleaseObligations / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  | 122,000,000 luv_SubleaseObligations / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  | 128,000,000 luv_SubleaseObligations / us-gaap_AircraftTypeAxis = us-gaap_B717200Member | 63,000,000 luv_SubleaseObligations / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |
Interest expense related to accretion |  | (5,000,000)luv_InterestExpenseAccretion / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  | (6,000,000)luv_InterestExpenseAccretion / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  |  |
Additional Estimated Loss on Sublease |  | 22,000,000 luv_AdditionalEstimatedLossonSublease / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  |  | 22,000,000 luv_AdditionalEstimatedLossonSublease / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |
Grounding Loss on Sublease |  | 9,000,000 luv_GroundingLossonSublease / us-gaap_AircraftTypeAxis = us-gaap_B717200Member |  |  |  |  |  |  |  |
B-717-200 | Minimum |  |  |  |  |  |  |  |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Sublease terms |  |  |  |  |  |  | 3 years |  |  |
B-717-200 | Maximum |  |  |  |  |  |  |  |  |  |
Capital Leased Assets [Line Items] |  |  |  |  |  |  |  |  |  |
Sublease terms |  |  |  |  |  |  | 9 years |  |  |
Love Field Airport |  |  |  |  |  |  |  |  |  |
Facility Operating leases |  |  |  |  |  |  |  |  |  |
2015 |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
2016 |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
2017 |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 24,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
2018 |  | 25,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 25,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
2019 |  | 25,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 25,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
Thereafter |  | 659,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | 659,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
Total minimum lease payments |  | $ 781,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDue / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |  |  | $ 781,000,000 us-gaap_OperatingLeasesFutureMinimumPaymentsDue / dei_LegalEntityAxis = luv_LoveFieldAirportMember |  |  |
[1] | Includes lease conversion cost payments

X
- Definition Additional estimated cost, at the scheduled date of delivery of each B717 to Delta (including the conversion, maintenance, and other contractual costs to be incurred), of the lease of the B717s, net of the future sublease income from Delta. + References No definition available. + Details
Name: | luv_AdditionalEstimatedLossonSublease
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The remaining estimated cost, at the scheduled date of delivery of each B717 to Delta (including the conversion, maintenance, and other contractual costs to be incurred), of the lease of the B717s currently accounted for as operating leases, net of the future sublease income from Delta. + References No definition available. + Details
Name: | luv_EstimatedLossOnSublease
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Additional cost due to the grounding of the B-717 Fleet as of December 28, 2014. + References No definition available. + Details
Name: | luv_GroundingLossonSublease
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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- Definition Interest Expense, Accretion + References No definition available. + Details
Name: | luv_InterestExpenseAccretion
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition The number of years the aircraft involved in the sale to the third party lessor will be under lease to the lessee. + References No definition available. + Details
Name: | luv_LeasebackPeriod
Namespace Prefix: | luv_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Lease terms for owned aircraft. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition The number of aircraft delivered to the sublessee. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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- Definition Number of Aircraft Expected To Be Converted to Sublease Per Month + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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- Definition The number of aircraft sold to third party aircraft lessors and immediately leased back by the Company in sale and leaseback transactions. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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- Definition Future minimum rental payments, net in aggregate as of the balance sheet date under operating leases. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future rental payments, net due within one year of the balance sheet date under an operating lease. + References No definition available. + Details
Name: | luv_OperatingLeasesFutureMinimumPaymentsNetCurrent
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future rental payments, net due within the fifth year of the balance sheet date under an operating lease. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future rental payments, net due within the fourth year of the balance sheet date under an operating lease. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future rental payments, net due within the third year of the balance sheet date under an operating lease. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future rental payments, net due within the second year of the balance sheet date under an operating lease. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Future minimum lease payments, net due under operating leases for periods greater than five years following the balance sheet date. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
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- Details
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- Definition The number of units (items of property) owned. + References No definition available. + Details
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Namespace Prefix: | luv_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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- Definition The number of units (items of property) under lease arrangements. + References No definition available. + Details
Name: | luv_PropertySubjectToOrAvailableForLeaseNumberOfUnitsTotal
Namespace Prefix: | luv_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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- Definition The gross proceeds received from the asset(s) sold in connection with the transaction involving the sale of property to another party and the lease back to the seller. + References No definition available. + Details
Name: | luv_SalesLeasebackTransactionGrossProceeds
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition The remaining estimated cost (including the conversion, maintenance, and other contractual costs to be incurred) of the lease of the B717s currently accounted for as operating leases, net of the future sublease income from Delta. + References No definition available. + Details
Name: | luv_SubleaseObligations
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Definition Sublease terms for leased aircraft. + References No definition available. + Details
Name: | luv_SubleaseTerms
Namespace Prefix: | luv_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Sublease Transaction Costs + References No definition available. + Details
Name: | luv_SubleaseTransactionCosts
Namespace Prefix: | luv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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- Definition Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition The number of units (items of property) under capital lease arrangements. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
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