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Noncontrolling Interests, Put Right, Exercise Price

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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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This element represents the total net income attributable to the parent for the period and the effect of net changes during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not result in a deconsolidation of the subsidiary from the consolidated financial statements.

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The increase (decrease) during the period impacting the parent's ownership interest in a subsidiary as it relates to the total (consolidated) equity attributable to the parent. The changes to the parent's ownership interest in a subsidiary represented by this element did not arise in a deconsolidation of the subsidiary from the consolidated financial statements.

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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 (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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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, $ in Millions		1 Months Ended	12 Months Ended
	Sep. 19, 2018 € / shares	Apr. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($) shares	Mar. 31, 2020 € / shares
Noncontrolling Interest [Line Items]
Put Right Value, Interest Rate Spread			5.00%
Carrying amount of redeemable noncontrolling interest			$ 1,402	$ 1,393
Noncontrolling interests			217	193
Net income attributable to noncontrolling interests			220	221	$ 230
Net income attributable to McKesson and transfers of interests			900	34	70
Redeemable Noncontrolling Interests
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests			42	45
Carrying amount of redeemable noncontrolling interest			1,402	1,393	1,459
Additional Paid-in Capital
Noncontrolling Interest [Line Items]
Effect of changes in ownership interests					3
McKesson Europe
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests			42	45	43
Put right (in euro per share) \| € / shares	€ 23.50					€ 22.99
Payments to purchase shares of Mckesson Europe					$ 50
Shares purchased (shares) \| shares					1.9
Maximum redemption value			$ 1,220	$ 1,230
Percentage of outstanding common shares			77.00%	77.00%
Put Right increase (euros per share) \| € / shares	€ 0.51
McKesson Europe \| Redeemable Noncontrolling Interests
Noncontrolling Interest [Line Items]
Decrease in carrying value of redeemable noncontrolling interest					$ 53
Vantage and ClarusOne Sourcing Services LLC
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests			$ 178	$ 176	$ 187
McKesson Europe
Noncontrolling Interest [Line Items]
Annual recurring compensation (in euro per share) \| € / shares						€ 0.83
Subsequent Event \| McKesson Europe
Noncontrolling Interest [Line Items]
Payments to purchase shares of Mckesson Europe		$ 46
Shares purchased (shares) \| shares		1.8
Percentage of outstanding common shares		78.00%