Fair Value Measurements, Investments and Notes Receivable - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
Jan. 31, 2023 aircraft	Dec. 31, 2022 USD ($) aircraft regional_carrier
Fair Value [Line Items]
Number of regional carriers \| regional_carrier		3
Investments in securities accounted for under the equity method \| $		$ 188
Carrying amount of loan receivable \| $		$ 101
Champlain
Fair Value [Line Items]
Number of regional aircraft		63
Republic
Fair Value [Line Items]
Number of regional aircraft		66
Champlain
Fair Value [Line Items]
Ownership stake		40.00%
Republic
Fair Value [Line Items]
Ownership stake		19.00%
Mesa Air Group, Inc. \| Subsequent Event
Fair Value [Line Items]
Number of regional aircraft	63
Ownership stake	10.00%
Potential number of aircraft operated	80
Fulcrum BioEnergy, Inc., Boom, Alder Fuels LLC, Heart Aerospace Incorporated and ZeroAvia, Inc.
Fair Value [Line Items]
Carrying value of other investment \| $		$ 434

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Fair Value [Line Items]

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Number of Regional Carriers

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Potential Number of Aircraft Operated

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of investment in equity security without readily determinable fair value.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Number of aircraft operated by the carrier.

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