REVENUE - Cargo and Other Revenue (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Revenue	$ 11,735	$ 10,426	$ 9,646
Cargo and other revenue
Disaggregation of Revenue [Line Items]
Revenue	348	252	248
Passenger | Cargo and other revenue
Disaggregation of Revenue [Line Items]
Revenue	169	128	133
Other Services | Cargo and other revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 179	$ 124	$ 115