EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator (basic and diluted):
Net income	$ 1,791	$ 1,721	$ 1,652
Less: Preferred stock dividends	73	29	14
Net income available to common stockholders	$ 1,718	$ 1,692	$ 1,638
Denominator:
Weighted-average common shares outstanding - basic (in shares)	449,731,453	478,822,072	502,157,440
Dilutive common shares: share-based awards (in shares)	1,482,248	1,608,669	1,527,651
Weighted-average common shares outstanding - diluted (in shares)	451,213,701	480,430,741	503,685,091
Earnings per common share:
Basic (in dollars per share)	$ 3.82	$ 3.54	$ 3.26
Diluted (in dollars per share)	$ 3.81	$ 3.52	$ 3.25
Antidilutive securities (in shares)	783	0	533