Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Jul. 31, 2021	Jul. 31, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 192	$ 324
Other comprehensive income (loss), net of tax:
Currency translation adjustments	(10)	62
Cash flow hedge adjustments	14	(45)
Postretirement benefits adjustments	4	7
Net other comprehensive income (loss)	8	24
Comprehensive income	$ 200	$ 348