Earnings Per Share - Reconciliation from Basic Earnings Per Share to Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Earnings Per Share [Abstract]
Net income available to common stockholders	$ 1,367	$ 1,092
Determination of shares:
Weighted average common shares outstanding	1,562.4	1,594.0
Assumed conversion of dilutive stock options and awards	35.1	40.4
DILUTED WEIGHTED AVERAGE COMMON SHARES OUTSTANDING	1,597.5	1,634.4
Earnings per common share:
Basic (in dollars per share)	$ 0.87	$ 0.69
Diluted (in dollars per share)	$ 0.86	$ 0.67