EARNINGS PER COMMON SHARE COMPUTATION (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income available for common stockholders	$ 644	$ 499	$ 1,328	$ 2,264
Weighted average outstanding shares of common stock used to compute basic earnings per common share (in shares)	137,709	144,215	137,792	145,546
Shares used to compute diluted earnings per common share (in shares)	138,678	145,360	138,695	146,622
Basic earnings per common share (in dollars per share)	$ 4.68	$ 3.46	$ 9.64	$ 15.56
Diluted earnings per common share (in dollars per share)	$ 4.65	$ 3.44	$ 9.58	$ 15.44
Number of antidilutive stock options and restricted stock excluded from computation (in shares)	36	399	284	595
Employee stock options
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dilutive effect of employee stock options and restricted stock (in shares)	186	165	199	174
Restricted stock
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dilutive effect of employee stock options and restricted stock (in shares)	783	980	704	902