Goodwill and Intangible Assets, Net - Schedule of Changes in the Carrying Amount of Goodwill (Details) $ in Millions	6 Months Ended
Sep. 30, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 9,493
Goodwill acquired	4
Foreign currency translation adjustments, net	(24)
Ending balance	9,473
Held-for-sale \| European Businesses (Disposal Group)
Goodwill [Roll Forward]
Intangible assets, net	279
U.S. Pharmaceutical
Goodwill [Roll Forward]
Beginning balance	3,963
Goodwill acquired	0
Foreign currency translation adjustments, net	(9)
Ending balance	3,954
Prescription Technology Solutions
Goodwill [Roll Forward]
Beginning balance	1,542
Goodwill acquired	0
Foreign currency translation adjustments, net	0
Ending balance	1,542
Medical-Surgical Solutions
Goodwill [Roll Forward]
Beginning balance	2,453
Goodwill acquired	0
Foreign currency translation adjustments, net	0
Ending balance	2,453
International
Goodwill [Roll Forward]
Beginning balance	1,535
Goodwill acquired	4
Foreign currency translation adjustments, net	(15)
Ending balance	$ 1,524

Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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