INCOME TAXES - Gross Unrecognized Tax Benefits, Including Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2019	May 31, 2018	May 31, 2017
Gross Unrecognized Tax Benefits Including Acquisitions [Abstract]
Gross unrecognized tax benefits as of June 1	$ 5,592	$ 4,919	$ 4,561
Increases related to tax positions from prior fiscal years	772	200	128
Decreases related to tax positions from prior fiscal years	(135)	(65)	(218)
Increases related to tax positions taken during current fiscal year	540	840	595
Settlements with tax authorities	(153)	(42)	(85)
Lapses of statutes of limitation	(202)	(273)	(47)
Cumulative translation adjustments and other, net	(66)		(15)
Cumulative translation adjustments and other, net	0	13
Total gross unrecognized tax benefits as of May 31	$ 6,348	$ 5,592	$ 4,919

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.

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