BASIS OF PRESENTATION AND RECENT ACCOUNTING PRONOUNCEMENTS Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018	Jun. 01, 2018	May 31, 2018
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating expense	$ 6,215	$ 6,361	$ 19,091	$ 19,266
Non-operating income, net	198	409	681	891
Retained earnings	(1,284)		(1,284)			$ 19,111
Effect of Tax Cuts and Jobs Act 2017 [Abstract]
Adjustment to one-time transition tax, tax cuts and jobs act 2017	376		529
Remeasurement of deferred tax assets and liabilities, tax cuts and jobs act 2017	140		140
Contract with Customer, Asset and Liability [Abstract]
Revenues recognized included in opening deferred revenue balance			7,700
Revenue, Performance Obligation [Abstract]
Remaining Performance Obligation, Amount, Total	$ 31,500		$ 31,500
Remaining Performance Obligation, Percentage, to be recognized in the next twelve months	62.00%		62.00%
Restricted Cash Equivalents [Abstract]
Restricted cash and cash equivalent item, description			Restricted cash that was included within cash and cash equivalents as presented within our condensed consolidated balance sheets as of February 28, 2019 and May 31, 2018 and our condensed consolidated statements of cash flows for the nine months ended February 28, 2019 and 2018 was nominal.
Sales of Financing Receivables [Abstract]
Sales of financing receivables	$ 274	360	$ 1,300	1,300
ASU 2017-07 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Operating expense		(14)		(41)
Non-operating income, net		$ (14)		$ (41)
ASU 2016-16 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Prepaid assets					$ (110)
Retained earnings					$ (110)