Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Revenue from Contract with Customer [Abstract]
Non-expiring flight credits issued					$ 7,900
Total operating revenues	$ 8,432	$ 7,244	$ 15,682	$ 13,672
Flight credits, expiration period			18 months
Flight credits (as a percent)	6.00%		6.00%		5.00%

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details