Operating Leases - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee, Lease, Description [Line Items]
Cash paid for amounts included in measurement of lease liabilities	$ 535	$ 464	$ 461
Aircraft and Aircraft Engines
Lessee, Lease, Description [Line Items]
Acquired aircraft and engines through operating leases	$ 864	$ 405