Revenue Recognition - Revenue Recognized By Revenue (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue from Contract with Customer [Abstract]
Passenger travel	$ 2,069	$ 2,087	$ 6,042	$ 6,402
Loyalty revenue - air transportation	129	114	476	440
Loyalty revenue	116	104	336	308
Other revenue	51	48	148	140
Total operating revenue	$ 2,365	$ 2,353	$ 7,002	$ 7,290

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