CAPITAL STOCK - Net Income (loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic:
Loss attributable to common stock	$ (386)	$ (360)	$ (4,866)	$ (407)
Weighted average number of shares outstanding, basic (in shares)	378	377	378	376
Basic net income (loss) per share (in USD per share)	$ (1.02)	$ (0.96)	$ (12.88)	$ (1.08)
Effect of Dilutive Securities:
Stock options and other (in shares)	0	0	0	0
Stock options and other (in USD per share)	$ 0	$ 0	$ 0	$ 0
Diluted:
Loss attributable to common stock	$ (386)	$ (360)	$ (4,866)	$ (407)
Income (loss) attributable to common stock, shares	378	377	378	376
Diluted net income (loss) per share (in USD per share)	$ (1.02)	$ (0.96)	$ (12.88)	$ (1.08)