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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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Redeemable Noncontrolling Interests, Maximum Redemption Value

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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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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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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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

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Redeemable Noncontrolling Interests and Noncontrolling Interests - Narrative (Details) shares in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)	Sep. 30, 2020 € / shares	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)
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%		5.00%
Decrease in carrying value of non-controlling interest	$ 50,000,000	$ 37,000,000	$ 93,000,000	$ 76,000,000
Associated increase in Company's ownership interest on its equity			3,000,000
Carrying value of redeemable noncontrolling interests	1,265,000,000		1,265,000,000				$ 1,402,000,000
Noncontrolling interests	200,000,000		200,000,000				217,000,000
Net income attributable to noncontrolling interests	50,000,000	53,000,000	100,000,000	107,000,000
Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests	10,000,000	11,000,000	21,000,000	22,000,000
Decrease in carrying value of non-controlling interest	0	0	0	0
Decrease in noncontrolling interest			(49,000,000)
Carrying value of redeemable noncontrolling interests	1,265,000,000	1,384,000,000	1,265,000,000	1,384,000,000		$ 1,414,000,000	1,402,000,000	$ 1,399,000,000	$ 1,393,000,000
Additional Paid-in Capital
Noncontrolling Interest [Line Items]
Associated increase in Company's ownership interest on its equity			3,000,000
Mckesson Europe Subsidiary
Noncontrolling Interest [Line Items]
Annual recurring dividend (in euro per share) \| € / shares					€ 0.83
Mckesson Europe Subsidiary
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests	10,000,000	11,000,000	21,000,000	22,000,000
Payments for purchase shares of Mckesson Europe			$ 49,000,000
Shares purchased (shares) \| shares			1.8
Carrying value of redeemable noncontrolling interests	1,300,000,000		$ 1,300,000,000				1,400,000,000
Maximum redemption value of redeemable noncontrolling interest	$ 1,200,000,000		$ 1,200,000,000				$ 1,200,000,000
Ownership percentage (as a percent)	78.00%		78.00%				77.00%
Vantage and ClarusOne Sourcing Services LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests	$ 200,000,000		$ 200,000,000				$ 217,000,000
Net income attributable to noncontrolling interests	$ 40,000,000	$ 42,000,000	$ 79,000,000	$ 85,000,000