Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 236	$ 240	$ 428	$ 564
Other comprehensive income (loss), net of tax:
Currency translation adjustments	(12)	4	(22)	66
Cash flow hedge adjustments	10	6	24	(39)
Postretirement benefits adjustments	4	5	8	12
Net other comprehensive income (loss)	2	15	10	39
Comprehensive income	$ 238	$ 255	$ 438	$ 603