Earnings Per Share - Reconciliation from Basic to Diluted Earnings Per Share (Detail) - $ / shares shares in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017
Determination of shares:
Weighted average common shares outstanding	1,581.4	1,627.0	1,587.7	1,633.1
Assumed conversion of dilutive stock options and awards	39.3	33.9	39.5	36.0
DILUTED WEIGHTED AVERAGE COMMON SHARES OUTSTANDING	1,620.7	1,660.9	1,627.2	1,669.1
Earnings per common share:
Basic (in dollars per share)	$ 0.54	$ 0.47	$ 1.22	$ 1.05
Diluted (in dollars per share)	$ 0.52	$ 0.46	$ 1.19	$ 1.03