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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.

No definition available.

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Additional cost due to the grounding of the B-717 Fleet as of December 28, 2014.

No definition available.

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Interest Expense, Accretion

No definition available.

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The number of years the aircraft involved in the sale to the third party lessor will be under lease to the lessee.

No definition available.

Name:	luv_LeasebackPeriod
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Lease terms for owned aircraft.

No definition available.

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The number of aircraft delivered to the sublessee.

No definition available.

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Number of Aircraft Expected To Be Converted to Sublease Per Month

No definition available.

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The number of aircraft sold to third party aircraft lessors and immediately leased back by the Company in sale and leaseback transactions.

No definition available.

Name:	luv_NumberOfAircraftSoldInSaleAndLeasebackTransaction
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Future minimum rental payments, net in aggregate as of the balance sheet date under operating leases.

No definition available.

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Future rental payments, net due within one year of the balance sheet date under an operating lease.

No definition available.

Name:	luv_OperatingLeasesFutureMinimumPaymentsNetCurrent
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Future rental payments, net due within the fifth year of the balance sheet date under an operating lease.

No definition available.

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Future rental payments, net due within the fourth year of the balance sheet date under an operating lease.

No definition available.

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Future rental payments, net due within the third year of the balance sheet date under an operating lease.

No definition available.

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Future rental payments, net due within the second year of the balance sheet date under an operating lease.

No definition available.

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Future minimum lease payments, net due under operating leases for periods greater than five years following the balance sheet date.

No definition available.

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The number of units (items of property) owned.

No definition available.

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The number of units (items of property) under lease arrangements.

No definition available.

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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.

No definition available.

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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.

No definition available.

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Sublease terms for leased aircraft.

No definition available.

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Sublease Transaction Costs

No definition available.

Name:	luv_SubleaseTransactionCosts
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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Name:	us-gaap_CapitalLeasedAssetsLineItems
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The number of units (items of property) under capital lease arrangements.

No definition available.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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Amount due based upon the occurrence of an event specified in the contractual terms.

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

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The estimate of the lease property's economic value at the end of the sales-type lease term excluding any amounts guaranteed by either the lessee or a third-party.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Term of the lessee's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

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Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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The number of units (items of property) under operating lease arrangements.

No definition available.

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