Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2021	Feb. 29, 2020	Feb. 28, 2021	Feb. 29, 2020
Statement Of Income And Comprehensive Income [Abstract]
NET INCOME	$ 892	$ 315	$ 3,363	$ 1,620
OTHER COMPREHENSIVE INCOME (LOSS):
Foreign currency translation adjustments, net of tax expense of $1 and $5 in 2021 and tax benefit of $6 and $3 in 2020	136	(1)	389	(12)
Amortization of prior service credit, net of tax benefit of $0 and $1 in 2021 and $7 and $19 in 2020	(2)	(20)	(6)	(61)
Other comprehensive income (loss)	134	(21)	383	(73)
COMPREHENSIVE INCOME	$ 1,026	$ 294	$ 3,746	$ 1,547