EQUITY METHOD INTERESTS - Summary of Combined Statement of Operations Equity Method Interests (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Operating income	$ 2,888	$ (4,102)	$ (2,152)
Net income	1,402	(4,904)	(3,682)
Equity Method Investment, Nonconsolidated Investee
Schedule of Equity Method Investments [Line Items]
Operating revenues	1,082	707	302
Operating income	548	331	121
Net income	468	256	120
Other comprehensive income (loss)	$ 4	$ 3	$ (8)