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, 2021	Aug. 31, 2020
Earnings Per Share [Abstract]
Net income available to common stockholders	$ 1,874	$ 1,518
Determination of shares:
Weighted average common shares outstanding (in shares)	1,581.9	1,561.8
Assumed conversion of dilutive stock options and awards (in shares)	37.7	31.5
DILUTED WEIGHTED AVERAGE COMMON SHARES OUTSTANDING (in shares)	1,619.6	1,593.3
Earnings per common share:
Basic (in dollars per share)	$ 1.18	$ 0.97
Diluted (in dollars per share)	$ 1.16	$ 0.95