EARNINGS PER SHARE - Calculation of EPS (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic EPS calculation
Net income (loss)	$ 99	$ 429	$ (262)
Less: Net income attributable to noncontrolling interests	(127)	(101)	(4)
NET (LOSS) INCOME ATTRIBUTABLE TO COMMON STOCK	(28)	328	(266)
Less: Net income allocated to participating securities	0	(7)	0
Net (loss) income available to common stockholders	$ (28)	$ 321	$ (266)
Weighted-average common shares outstanding	49,000,000.0	47,400,000	42,500,000
Basic EPS (in dollars per share)	$ (0.57)	$ 6.77	$ (6.26)
Diluted EPS calculation
Net income (loss)	$ 99	$ 429	$ (262)
Less: Net income attributable to noncontrolling interests	(127)	(101)	(4)
NET (LOSS) INCOME ATTRIBUTABLE TO COMMON STOCK	(28)	328	(266)
Less: Net income allocated to participating securities	0	(7)	0
Net (loss) income available to common stockholders	$ (28)	$ 321	$ (266)
Weighted-average common shares outstanding	49,000,000.0	47,400,000	42,500,000
Dilutive effect of potentially dilutive securities (in shares)	0	0	0
Diluted EPS (in dollars per share)	$ (0.57)	$ 6.77	$ (6.26)
Weighted-average antidilutive shares	3.1	1.6	2.3