ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2018
Contract with Customer, Asset and Liability [Abstract]
Revenues recognized included in opening deferred revenue balance	$ 8,400	$ 8,300
Impairment losses recognized on receivables	0	0	$ 0
Revenue, Performance Obligation [Abstract]
Remaining Performance Obligation, Amount, Total	$ 37,000
Remaining Performance Obligation, Percentage, to be recognized in the next twelve months	62.00%
Sales of Financing Receivables [Abstract]
Sales of financing receivables	$ 1,500	1,800	1,700
Inventory Net [Abstract]
Total inventories	211	320
Other Receivables [Narrative] [Abstract]
Other receivables included in prepaid expenses and other current assets	778	776
Goodwill, Intangible Assets and Impairment Assessments [Abstract]
Goodwill impairment loss	0	0	0
Foreign Currency [Abstract]
Net foreign exchange transaction losses included in non-operating income, net	$ 185	111	74
Stock-Based Compensation [Abstract]
Service period of award	4 years
Advertising [Abstract]
Advertising expenses	$ 178	$ 169	$ 138
Minimum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, estimated useful lives	1 year
Goodwill, Intangible Assets and Impairment Assessments [Abstract]
Finite lived intangible assets, useful life	1 year
Maximum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, estimated useful lives	40 years
Goodwill, Intangible Assets and Impairment Assessments [Abstract]
Finite lived intangible assets, useful life	10 years