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Noncontrolling Interests, Put Right, Exercise Price

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Noncontrolling Interests, Put Right, Exercise Price, Increase

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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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Aggregate dividends paid during the period for each share of common stock outstanding.

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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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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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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 Units, shares in Millions		3 Months Ended		9 Months Ended
	Sep. 19, 2018 € / shares $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2018 € / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) shares	Dec. 31, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 02, 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%
Carrying value of redeemable noncontrolling interests							$ 1,404,000,000	$ 1,459,000,000
Noncontrolling Interests							204,000,000	253,000,000
Net income attributable to noncontrolling interests		$ 57,000,000	$ 58,000,000		$ 169,000,000	$ 169,000,000
Net Income (Loss) Attributable to Parent		469,000,000	903,000,000		830,000,000	1,213,000,000
Net income attributable to McKesson and transfers from noncontrolling interests					830,000,000	1,216,000,000
Mckesson Europe Subsidiary
Noncontrolling Interest [Line Items]
Dividend (in usd per share) \| € / shares				€ 0.83
Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Net income attributable to noncontrolling interests					34,000,000	32,000,000
Decrease in redeemable noncontrolling interests						53,000,000
Carrying value of redeemable noncontrolling interests			1,435,000,000			1,435,000,000	1,404,000,000	1,459,000,000	$ 1,327,000,000
Additional Paid-in Capital
Noncontrolling Interest [Line Items]
Effect of changes in ownership interests with noncontrolling interests						3,000,000
Mckesson Europe Subsidiary
Noncontrolling Interest [Line Items]
One-time guaranteed dividend (in usd per share) \| € / shares										€ 0.83
Net income attributable to noncontrolling interests		11,000,000	12,000,000		34,000,000	32,000,000
Put right redemption price per share (in euros per share) \| € / shares	€ 23.50
Payments to acquire shares of Celesio						$ 50,000,000
Number of redeemable noncontrolling interest shares repurchased (shares) \| shares						1.9
Carrying value of redeemable noncontrolling interests							1,400,000,000	1,460,000,000
Maximum redemption value of redeemable noncontrolling interest							$ 1,258,000,000.000	$ 1,350,000,000.00
Ownership percentage (as a percent)							77.00%	77.00%
Increase in Put Amount (in euros per share) \| $ / shares	€ 0.51
Mckesson Europe Subsidiary \| Redeemable Noncontrolling Interest
Noncontrolling Interest [Line Items]
Decrease in redeemable noncontrolling interests						$ 53,000,000
Vantage and ClarusOne Sourcing Services LLC
Noncontrolling Interest [Line Items]
Noncontrolling Interests							$ 204,000,000	$ 253,000,000
Net income attributable to noncontrolling interests		$ 46,000,000	$ 46,000,000		$ 135,000,000	$ 137,000,000