Revenue Recognition - Passenger Revenue (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Disaggregation of Revenue [Line Items]
Operating revenue	$ 9,348	$ 4,150
Passenger
Disaggregation of Revenue [Line Items]
Operating revenue	6,907	2,748
Ticket
Disaggregation of Revenue [Line Items]
Operating revenue	5,986	2,277
Loyalty travel awards
Disaggregation of Revenue [Line Items]
Operating revenue	543	241
Travel-related services
Disaggregation of Revenue [Line Items]
Operating revenue	$ 378	$ 230

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