EARNINGS PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Aug. 31, 2013		Aug. 31, 2012
Computation of Basic and Diluted Earnings Per Share [Abstract]
Net income	$ 2,191		$ 2,034
Weighted average common shares outstanding	4,608		4,867
Dilutive effect of employee stock plans	66		72
Dilutive weighted average common shares outstanding	4,674		4,939
Basic earnings per share	$ 0.48		$ 0.42
Diluted earnings per share	$ 0.47		$ 0.41
Shares subject to anti-dilutive stock options and restricted stock-based awards excluded from calculation	289	[1]	188	[1]

[1] These weighted shares relate to anti-dilutive stock options and restricted stock-based awards as calculated using the treasury stock method and could be dilutive in the future.