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Finance Leases, Net Investment in Sales Type Leases, Unguaranteed Residual Values of Leased Property

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- Definition

Lessee Operating Lease Terms of Contract

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Lessee Operating and Finance Lease Term of Contract

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- Definition

Operating Leases Future Minimum Payments Due in Six Years

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The number of units (items of property) owned.

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

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Sublease Terms

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

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- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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 the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Leases (Details)	3 Months Ended	12 Months Ended
Leases (Details)	Sep. 30, 2017 USD ($)	Dec. 31, 2019 USD ($) aircraft	Dec. 31, 2018 USD ($) aircraft Years
Property Subject to or Available for Operating Lease, Number of Units \| Years			51
Sublease Income		$ 97,000,000
Sublease income - 2020		78,000,000	$ 357,000,000
Sublease income - 2021		41,000,000	244,000,000
Sublease income - 2022		17,000,000	172,000,000
Sublease income - 2023		7,000,000	146,000,000
Sublease income - 2024		1,000,000
Unrecorded Unconditional Purchase Obligation		$ 543,000,000
Lessee, Operating Lease, Lease Not yet Commenced, Description \| aircraft		16
Capital Leased Assets, Gross			1,300,000,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation			$ 304,000,000
September 2017 Remaining -300 Aircraft grounding charge	$ 63,000,000
B-717-200
Property Subject to or Available for Operating Lease, Number of Units \| aircraft		65	73
Finance Leases, Net Investment in Sales Type Leases, Contingent Payments on Leased Property		$ 0
Finance Leases, Net Investment in Sales Type Leases, Unguaranteed Residual Values of Leased Property		$ 0
Finance Leased Assets, Number of Units \| aircraft		2
Property Subject To Or Available For Lease, Number Of Units, Total \| aircraft		88
Property Subject To Or Available For Lease Remaining, Number Of Units, Total \| aircraft		85
Minimum \| B-717-200
Sublease Terms		1 month
Minimum \| 737 MAX 8
Lessee, Renewal Term		8 years
Minimum \| Aircraft
Lessee, Renewal Term		1 year
Lessee Operating and Finance Lease Term of Contract		1 month
Minimum \| Airport-Related
Lessee, Renewal Term		1 year
Lessee Operating Lease Terms of Contract		1 month
Minimum \| Other Property
Lessee, Renewal Term		6 months
Lessee Operating and Finance Lease Term of Contract		2 months
Maximum \| B-717-200
Sublease Terms		5 years
Maximum \| 737 MAX 8
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract		9 years
Maximum \| Aircraft
Lessee, Renewal Term		6 years
Lessee Operating and Finance Lease Term of Contract		12 years
Maximum \| Airport-Related
Lessee, Renewal Term		10 years
Lessee Operating Lease Terms of Contract		27 years
Maximum \| Other Property
Lessee, Renewal Term		5 years
Lessee Operating and Finance Lease Term of Contract		7 years
Property Available for Operating Lease [Member]
Property Subject to or Available for Operating Lease, Number of Units \| aircraft			124
Assets Sold to Third Party \| B-717-200
Owned Assets, Number of Units \| aircraft		10
Lease Expired \| B-717-200
Property Subject to or Available for Operating Lease, Number of Units \| aircraft		8
Property Subject To Or Available For Lease, Number Of Units, Total \| aircraft			3