EARNINGS PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Feb. 28, 2013		Feb. 29, 2012		Feb. 28, 2013		Feb. 29, 2012
Computation of Basic and Diluted Earnings Per Share [Abstract]
Net income	$ 2,504		$ 2,498		$ 7,119		$ 6,529
Weighted average common shares outstanding	4,735		5,007		4,798		5,037
Dilutive effect of employee stock plans	77		73		75		81
Dilutive weighted average common shares outstanding	4,812		5,080		4,873		5,118
Basic earnings per share	$ 0.53		$ 0.50		$ 1.48		$ 1.30
Diluted earnings per share	$ 0.52		$ 0.49		$ 1.46		$ 1.28
Shares subject to anti-dilutive stock options and restricted stock-based awards excluded from calculation	210	[1]	118	[1]	207	[1]	106	[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.