Revenue Recognition - Revenue Recognized By Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Passenger travel	$ 1,792	$ 1,888
Loyalty revenue - air transportation	177	167
Loyalty revenue	122	107
Other revenue	49	47
Total operating revenue	$ 2,140	$ 2,209

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