Adjustments to Additional Paid in Capital, Exercise of Put Right

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Annual Recurring Compensation Per Share to Noncontrolling Interests

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Noncontrolling Interest, Decrease for Exercise of Put Right

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Noncontrolling Interests, Put Right, Exercise Price

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Put Right Value, Interest Rate Spread

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Reclassification of Temporary Equity to Noncontrolling Interest

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Repurchase of Redeemable Noncontrolling Interest, Shares Repurchased

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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

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The cash outflow during the period for redemption of redeemable noncontrolling interests.

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Redeemable Noncontrolling Interests and Noncontrolling Interests - Narrative (Details) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($) shares	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2014 € / shares
Noncontrolling Interest [Line Items]
Put right redemption price per share (in euros per share) \| € / shares									€ 22.99
Put right value, interest rate spread (as a percent)									5.00%
Payments for purchase shares of McKesson Europe			$ 0	$ 1,031
Associated increase in Company's ownership interest on its equity				8
Reclassification of McKesson Europe AG redeemable noncontrolling interests				287
Noncontrolling interests	$ 518		518			$ 480
Net income attributable to noncontrolling interests	41	$ 43	82	90
Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests		0		8
Decrease in noncontrolling interest				(983)
Reclassification of McKesson Europe AG redeemable noncontrolling interests				(287)
Additional Paid-in Capital
Noncontrolling Interest [Line Items]
Associated increase in Company's ownership interest on its equity				178
Noncontrolling Interests
Noncontrolling Interest [Line Items]
Decrease in noncontrolling interest				0
Reclassification of McKesson Europe AG redeemable noncontrolling interests				287
Noncontrolling interests	518	484	518	484	$ 532	$ 480	$ 484	$ 196
Net income attributable to noncontrolling interests	41	43	82	82
McKesson Europe Subsidiary
Noncontrolling Interest [Line Items]
Annual recurring dividend (in euro per share) \| € / shares									€ 0.83
McKesson Europe Subsidiary \| Noncontrolling Interests
Noncontrolling Interest [Line Items]
Noncontrolling interests	382		382
McKesson Europe Subsidiary
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests				8
Payments for purchase shares of McKesson Europe				$ 1,000
Shares purchased (in shares) \| shares				34.5
Vantage, ClarusOne Sourcing Services LLC and McKesson Europe
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests	$ 41	$ 43	$ 82	$ 82