Revenue Derived From Services, Percentage

No definition available.

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6c)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6a)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.L)
-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e99989-122729

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6b)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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- Definition

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.

+ References

No definition available.

+ Details

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Segments of Business - Narrative (Details) $ in Millions	3 Months Ended											12 Months Ended
Segments of Business - Narrative (Details) $ in Millions	Jun. 30, 2018 segment	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| segment												2
Goodwill impairment charge												$ 1,738	$ 290	$ 0
Pre-tax charge												13	14	229
Charges (credits) associated with last-in-first-out inventory method												(99)	(7)	244
Corporate
Segment Reporting Information [Line Items]
Pre-tax charge												0	5	$ 17
Distribution Solutions
Segment Reporting Information [Line Items]
Goodwill impairment charge												$ 1,738	$ 0
Distribution Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Percentage of total revenue (less than) (as a percent)												2.00%	2.00%	2.00%
Pre-tax charge												$ 13	$ 19	$ 161
Net cash proceeds							$ 2		$ 142				144	76
Charges (credits) associated with last-in-first-out inventory method		$ (94)	$ (2)	$ (29)	$ 26	$ 144	$ (155)	$ (43)	$ 47
Distribution Solutions \| Operating Segments \| ZEE Medical Business
Segment Reporting Information [Line Items]
Pre-tax gain on sale of business										$ 52				52
Technology Solutions
Segment Reporting Information [Line Items]
Goodwill impairment charge												0	290
Technology Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Goodwill impairment charge								$ 290
Pre-tax charge												0	(10)	51
Technology Solutions \| Operating Segments \| Core MTS Businesses
Segment Reporting Information [Line Items]
Pre-tax gain on sale of business						$ 3,947							3,947
Technology Solutions \| Operating Segments \| Nurse Triage
Segment Reporting Information [Line Items]
Pre-tax gain on sale of business											$ 51			51
Cost Alignment Plan
Segment Reporting Information [Line Items]
Pre-tax charge												13	$ 14	$ 229
Disposal Group, Held-for-sale, Not Discontinued Operations \| Enterprise Information Solutions
Segment Reporting Information [Line Items]
Pre-tax gain on sale of business			$ 109
Mckesson Europe Reporting Unit
Segment Reporting Information [Line Items]
Goodwill impairment charge												1,283
Mckesson Europe Reporting Unit \| Distribution Solutions
Segment Reporting Information [Line Items]
Goodwill impairment charge		933		350
Rexall Health \| Distribution Solutions
Segment Reporting Information [Line Items]
Goodwill impairment charge		455										455
Intangible Asset and Store Assets Impairment
Segment Reporting Information [Line Items]
Pre-tax charge												479
Intangible Asset and Store Assets Impairment \| Fiscal 2018 McKesson Europe Plan
Segment Reporting Information [Line Items]
Pre-tax charge		$ 257		$ 189								446
Severance and Lease Exit Costs \| Fiscal 2018 McKesson Europe Plan
Segment Reporting Information [Line Items]
Pre-tax charge												$ 74
Expected
Segment Reporting Information [Line Items]
Number of operating segments \| segment	3