Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2019	Oct. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 282	$ 249	$ 468	$ 449
Other comprehensive income (loss), net of tax:
Currency translation adjustments	11	(27)	(3)	(39)
Cash flow hedge adjustments	(7)	22	2	45
Postretirement benefits adjustments	3	4	7	7
Net other comprehensive income (loss)	7	(1)	6	13
Comprehensive income	$ 289	$ 248	$ 474	$ 462

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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