INCOME TAXES Continued (Details) - USD ($) $ in Millions	12 Months Ended
	May. 31, 2015	May. 31, 2014	May. 31, 2013
Components of Deferred Tax Assets and Liabilities [Abstract]
Current deferred tax assets	$ 663	$ 914
Non-current deferred tax assets	795	837
Current deferred tax liabilities (in other current liabilities)	(85)	(129)
Non-current deferred tax liabilities (in other non-current liabilities)	(380)	(258)
Net deferred tax assets	993	1,364
Reconciliation of Differences Between Amount Computed by Applying Federal Statutory Rate to our Income Before Provision for Income Taxes and Provision for Income Taxes [Abstract]
Tax provision at statutory rate	4,492	4,796	$ 4,865
Foreign earnings at other than United States rates	(1,627)	(1,790)	(1,637)
State tax expense, net of federal benefit	176	154	299
Settlements and releases from judicial decisions and statute expirations, net	(85)	(168)	(144)
Domestic production activity deduction	(188)	(174)	(155)
Other, net	128	(69)	(255)
Total provision for income taxes	$ 2,896	$ 2,749	$ 2,973