Discontinued Operation (Details) (USD $) In Millions	3 Months Ended	6 Months Ended
Sep. 30, 2010	Sep. 30, 2010
Net sales proceeds		$ 109
Discontinued operation - gain on sale, net of tax	72	72
McKesson Asia Pacific Pty Limited [Member]
Utilization of capital loss carry-forwards, previously recorded as valuation allowance		15
Technology Solutions [Member]
Net sales proceeds		109
Pre tax gain from divestiture		95
Discontinued operation - gain on sale, net of tax		$ 72

Pretax gain (loss), not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

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-Section 45

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 144

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

-Section 50

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