Gain (Loss) on Derecognition of Liability

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- Definition

Gain (Loss) on Disposition of Business After Tax

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No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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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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No definition available.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount after tax of loss recognized that results from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

No definition available.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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The change in the inventory reserve representing the cumulative difference in cost between the first in, first out and the last in, first out inventory valuation methods, which change has been reflected in the statement of income during the period.

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- Definition

Cash received for the settlement of litigation during the current period.

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Cash inflow representing an adjustment to the purchase price of a previous acquisition.

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Quarterly Financial Information (Unaudited) - Narrative (Details) $ in Millions, $ in Millions			3 Months Ended								6 Months Ended		12 Months Ended
	May 23, 2018 USD ($)	May 23, 2018 CAD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2017 CAD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Quarterly Financial Information [Line Items]
Pretax charges (credits) related to last-in-first-out method of accounting for inventory			$ (146)	$ (21)	$ (22)	$ (21)	$ (94)	$ (2)	$ (29)	$ 26			$ (210)	$ (99)	$ (7)
Net cash proceeds from settlements			63	104		35
Goodwill impairment charge													1,797	1,738	290
Long-lived asset impairment charges, before tax			190			20
Proportionate share of income (loss) from Change Healthcare							23	(90)	(61)	$ (120)
Goodwill impairment, net of tax														1,738
Pre-tax gain on sale of business													0	109	0
Disposal Group, Held-for-sale, Not Discontinued Operations \| Enterprise Information Solutions
Quarterly Financial Information [Line Items]
Pre-tax gain on sale of business								109						109
Gain from sale of business, after tax								$ 30
Intangible Asset and Store Assets Impairment \| Fiscal 2018 McKesson Europe Plan
Quarterly Financial Information [Line Items]
Long-lived asset impairment charges, before tax							257		189
European Pharmaceutical Solutions
Quarterly Financial Information [Line Items]
Goodwill impairment charge			1,206			570							1,776	1,283
Long-lived asset impairment charges, before tax													210	446
Proportionate share of income (loss) from Change Healthcare													43	32	30
Goodwill impairment, net of tax													1,756	1,283
Technology Solutions
Quarterly Financial Information [Line Items]
Goodwill impairment charge															290
Goodwill impairment, net of tax															282
Change Healthcare
Quarterly Financial Information [Line Items]
Proportionate share of income (loss) from Change Healthcare			$ (32)	(50)	(56)	$ (56)							(194)	(248)	0
Operating Segments \| Technology Solutions \| Core MTS Businesses
Quarterly Financial Information [Line Items]
Gain from sale of business, after tax															$ 3,000
Operating Segments \| Change Healthcare \| Technology Solutions \| Core MTS Businesses
Quarterly Financial Information [Line Items]
Pre-tax gain on sale of business														37
Gain from sale of business, after tax														22
CANADA \| Rexall Health \| Third Party Seller of Rexall Health
Quarterly Financial Information [Line Items]
Proceeds from escrow settlement related to previous Acquisition	$ 97	$ 125									$ 119	$ 147	97
Mckesson Europe Reporting Unit \| European Pharmaceutical Solutions
Quarterly Financial Information [Line Items]
Goodwill impairment charge							933		350
Goodwill impairment, net of tax									$ 350
Rexall Health
Quarterly Financial Information [Line Items]
Goodwill impairment charge							$ 455
Long-lived asset impairment charges, before tax				$ 35									35	488
Corporate Joint Venture \| Change Healthcare
Quarterly Financial Information [Line Items]
Proportionate share of income (loss) from Change Healthcare													(194)	$ (248)
Pre-tax credit representing reduction in TRA liability					$ 90								$ (90)