BASIS OF PRESENTATION, RECENT ACCOUNTING PRONOUNCEMENTS AND OTHER Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Net discrete tax benefit			$ 2,300
Deferred tax asset	$ 11,300		11,300
Non-current deferred tax liability	9,100		9,100
Contract with Customer, Asset and Liability [Abstract]
Revenues recognized included in opening deferred revenues balances			7,400	$ 7,700
Revenue, Performance Obligation [Abstract]
Remaining Performance Obligation, Amount, Total	$ 35,300		$ 35,300
Remaining Performance Obligation, Percentage, to be recognized in the next twelve months	61.00%		61.00%
Sales of Financing Receivables [Abstract]
Sales of financing receivables	$ 338	$ 284	$ 1,300	$ 1,200