Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Statement Of Income And Comprehensive Income [Abstract]
NET INCOME	$ 739	$ 2,074	$ 2,509	$ 3,445
OTHER COMPREHENSIVE INCOME (LOSS):
Foreign currency translation adjustments, net of tax expense of $9 and tax benefit of $22 in 2019 and tax expense of $9 and $26 in 2018	103	100	(90)	119
Amortization of prior service credit, net of tax benefit of $7 and $21 in 2019 and tax benefit of $7 and $29 in 2018	(23)	(23)	(69)	(61)
Other comprehensive income (loss)	80	77	(159)	58
COMPREHENSIVE INCOME	$ 819	$ 2,151	$ 2,350	$ 3,503