Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Apr. 30, 2021	Apr. 30, 2020
Goodwill [Roll Forward]
Beginning balance	$ 756	$ 753
Sale of business	(4)
Acquisition of business	8	11
Foreign currency translation adjustment	19	(8)
Impairment		0
Ending balance	779	756
Indefinite-lived Intangible Assets [Roll Forward]
Beginning balance	635	645
Sale of business	(1)
Acquisition of business	8	12
Foreign currency translation adjustment	34	(9)
Impairment		(13)
Ending balance	$ 676	$ 635

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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