EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Aug. 31, 2019	Aug. 31, 2018
Earnings Per Share [Abstract]
Net income		$ 2,137	$ 2,265
Weighted average common shares outstanding		3,317	3,904
Dilutive effect of employee stock plans		93	95
Dilutive weighted average common shares outstanding		3,410	3,999
Basic earnings per share		$ 0.64	$ 0.58
Diluted earnings per share		$ 0.63	$ 0.57
Shares subject to anti-dilutive restricted stock-based awards and stock options excluded from calculation	[1]	55	81

[1] These weighted shares relate to anti-dilutive restricted service based stock-based awards and stock options as calculated using the treasury stock method and contingently issuable shares under performance-based stock option (PSO) and performance-based restricted stock unit award (PSU) arrangements. Such shares could be dilutive in the future.