EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Numerator (basic and diluted):
Net income	$ 34	$ 439
Less: Preferred stock dividends	22	15
Net income available to common stockholders	$ 12	$ 424
Denominator:
Weighted-average common shares outstanding - basic (in shares)	427,718,421	460,713,172
Dilutive common shares: share-based awards (in shares)	1,670,434	1,807,508
Weighted-average common shares outstanding - diluted (in shares)	429,388,855	462,520,680
Earnings per common share:
Basic (in dollars per share)	$ 0.03	$ 0.92
Diluted (in dollars per share)	$ 0.03	$ 0.92
Share-based awards excluded from diluted earnings per share computation (in shares)	1,670,434	939,698