Revenue Recognition - Revenue Recognized By Revenue (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Passenger revenue
Passenger travel	$ 7,983	$ 8,403	$ 8,078
Loyalty revenue - air transportation	634	605	508
Other revenue
Loyalty revenue	464	422	391
Other revenue	198	185	181
Total operating revenue	$ 9,279	$ 9,615	$ 9,158

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