Redeemable Noncontrolling Interests and Noncontrolling Interests - Schedule of Changes in Redeemable Noncontrolling Interests and Noncontrolling Interests (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Noncontrolling Interests
Beginning balance			$ 480
Net income attributable to noncontrolling interests	$ 41	$ 43	82	$ 90
Payments to noncontrolling interests	(41)	(40)	(77)	(79)
Ending balance	518		518
Redeemable Noncontrolling Interests
Payments to noncontrolling interests	(41)	(40)	(77)	(79)
Reclassification of McKesson Europe AG redeemable noncontrolling interests				287
Noncontrolling Interests
Noncontrolling Interests
Beginning balance	532	484	480	196
Net income attributable to noncontrolling interests	41	43	82	82
Other comprehensive income	(6)		44	0
Reclassification of recurring compensation to other accrued liabilities	2	(2)	4	(2)
Payments to noncontrolling interests	(41)	(40)	(77)	(79)
Other	(6)	(1)	(7)	0
Ending balance	518	484	518	484
Redeemable Noncontrolling Interests
Other comprehensive income	(6)		44	0
Payments to noncontrolling interests	(41)	(40)	(77)	(79)
Decrease in noncontrolling interest				0
Reclassification of McKesson Europe AG redeemable noncontrolling interests				287
Other	$ 6	1	$ 7	0
Redeemable Noncontrolling Interest
Noncontrolling Interests
Other comprehensive income				3
Reclassification of recurring compensation to other accrued liabilities		0		(8)
Payments to noncontrolling interests		0		0
Other		(7)		(4)
Redeemable Noncontrolling Interests
Beginning balance		7		1,271
Net income attributable to noncontrolling interests		0		8
Other comprehensive income				3
Payments to noncontrolling interests		0		0
Decrease in noncontrolling interest				(983)
Reclassification of McKesson Europe AG redeemable noncontrolling interests				(287)
Other		7		4
Ending balance		$ 0		$ 0

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests.

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