BASIS OF PRESENTATION, RECENT ACCOUNTING PRONOUNCEMENTS AND OTHER (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Nov. 30, 2020	Nov. 30, 2019	Nov. 30, 2020	Nov. 30, 2019
Acquisition Related and Other Expenses [Abstract]
Transitional and other employee related costs	$ 1	$ 3	$ 3	$ 7
Business combination adjustments, net	0	(4)	1	2
Other, net	75	13	91	28
Total acquisition related and other expenses	76	12	95	37
Non-Operating Income, net [Abstract]
Interest income	27	145	58	335
Foreign currency losses, net	(16)	(26)	(66)	(80)
Noncontrolling interests in income	(43)	(46)	(81)	(87)
Other, net	21	19	76	23
Total non-operating (expenses) income, net	$ (11)	$ 92	$ (13)	$ 191