EARNINGS PER COMMON SHARE - Basic and Diluted Earnings Per 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
Earnings Per Share [Abstract]
Weighted average number of shares outstanding - basic (in shares)	450.4	491.1	455.8	504.5
Effect of dilutive securities common shares, employee stock awards (in shares)	0.0	0.8	1.4	0.0
Weighted average common shares outstanding - diluted (in shares)	450.4	491.9	457.1	504.5
Net income (loss)	$ (3,942)	$ 430	$ 1,505	$ (279)
Less: Net income (loss) attributable to the noncontrolling interest	86	67	123	133
Net income (loss) attributable to Holdings	(4,028)	363	1,382	(412)
Less: Preferred stock dividends	10	0	23	0
Net income (loss) available to Holdings’ common shareholders	$ (4,038)	$ 363	$ 1,359	$ (412)
Net income (loss) attributable to Holdings per common share:
Basic (in usd per share)	$ (8.96)	$ 0.74	$ 2.98	$ (0.82)
Diluted (in usd per share)	$ (8.96)	$ 0.74	$ 2.97	$ (0.82)
Effect of dilutive securities (in shares)	1.0			0.6