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Fair Value Measurements, Investments and Notes Receivable - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2023 USD ($) aircraft
Fair Value [Line Items] |
Investments in securities accounted for under the equity method | $ 230
Carrying amount of loan receivable | $ 103
Maximum | Corporate Debt |
Fair Value [Line Items] |
Available for sale investment maturity term | 15 months
Champlain |
Fair Value [Line Items] |
Number of regional aircraft | aircraft | 53
Republic |
Fair Value [Line Items] |
Number of regional aircraft | aircraft | 66
Champlain |
Fair Value [Line Items] |
Ownership stake | 40.00%
Republic |
Fair Value [Line Items] |
Ownership stake | 19.00%
UAV Fund |
Fair Value [Line Items] |
Ownership stake | 38.00%
Fulcrum BioEnergy, Inc., Boom, Alder Fuels LLC, Heart Aerospace Incorporated and ZeroAvia, Inc. |
Fair Value [Line Items] |
Carrying value of other investment | $ 401

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