REVENUE - Air Traffic Liability Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Air Traffic Liability [Roll Forward]
Air traffic liability - beginning balance	$ 8,279	$ 8,250
Current period sales	25,057	23,766
Revenue from amounts included in contract liability opening balances	(5,082)	(5,031)
Revenue from current period sales	(20,012)	(18,706)
Air traffic liability - ending balance	$ 8,242	$ 8,279