Revenue - Air Traffic Liability Breakout (Details) - USD ($) $ in Millions	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Air traffic liability - passenger travel and ancillary passenger services	$ 3,540		$ 2,936
Air traffic liability - loyalty program	4,885	$ 4,885	4,789	$ 4,772	$ 4,719	$ 4,447
Total Air traffic liability	$ 8,425		$ 7,725	$ 8,236		$ 7,133