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DERIVATIVE INSTRUMENTS - INCOME STATEMENT (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Gains (losses) recognized in interest income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Loss expected to be reclassified	$ (6)
Interest rate swaps agreements [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Losses recognized in income	8
Derivative Instruments Not Designated as Hedges [Member] \| Fuel hedge contracts [Member] \| Gains (losses) recognized in aircraft fuel expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on Derivative Instruments, Net, Pretax	(62)	$ 93	$ 104
Cash Flow Hedging [Member] \| Derivative Instruments Designated as Hedges [Member] \| Interest rate swaps agreements [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	$ (7)	$ 23	$ 17