EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
		May 31, 2021	May 31, 2020	May 31, 2019
Earnings Per Share [Abstract]
Net income		$ 13,746	$ 10,135	$ 11,083
Weighted average common shares outstanding		2,945	3,211	3,634
Dilutive effect of employee stock plans		77	83	98
Dilutive weighted average common shares outstanding		3,022	3,294	3,732
Basic earnings per share		$ 4.67	$ 3.16	$ 3.05
Diluted earnings per share		$ 4.55	$ 3.08	$ 2.97
Shares subject to anti-dilutive restricted stock-based awards and stock options excluded from calculation	[1]	36	56	71

[1] These weighted shares relate to anti-dilutive restricted stock-based awards and stock options, both of which were service-based, as calculated using the treasury stock method and contingently issuable shares, substantially all of which were related to PSO agreements. Such shares could be dilutive in the future. See Note 13 for information regarding the exercise prices of our outstanding, unexercised stock options.