INCOME TAXES - Gross Unrecognized Tax Benefits, Including Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Gross Unrecognized Tax Benefits Including Acquisitions [Abstract]
Gross unrecognized tax benefits as of June 1	$ 4,919	$ 4,561	$ 4,038
Increases related to tax positions from prior fiscal years	200	128	350
Decreases related to tax positions from prior fiscal years	(65)	(218)	(111)
Increases related to tax positions taken during current fiscal year	833	595	461
Settlements with tax authorities	(42)	(85)	(73)
Lapses of statutes of limitation	(273)	(47)	(73)
Cumulative translation adjustments and other, net		(15)	(31)
Cumulative translation adjustments and other, net	13
Total gross unrecognized tax benefits as of May 31	$ 5,585	$ 4,919	$ 4,561

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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