INCOME TAXES Continued (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2016	May 31, 2015	May 31, 2014
Components of Deferred Tax Assets and Liabilities [Abstract]
Non-current deferred tax assets	$ 1,291	$ 1,458
Non-current deferred tax liabilities (in other non-current liabilities)	(160)	(465)
Net deferred tax assets	1,131	993
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	4,005	4,492	$ 4,796
Foreign earnings at other than United States rates	(1,284)	(1,627)	(1,790)
State tax expense, net of federal benefit	176	176	154
Settlements and releases from judicial decisions and statute expirations, net	(150)	(85)	(168)
Domestic production activity deduction	(155)	(188)	(174)
Other, net	(51)	128	(69)
Total provision for income taxes	$ 2,541	$ 2,896	$ 2,749