Segment Information (Details) (USD $) In Millions	3 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Revenues
Segment Reporting Revenue From External Customers	$ 29,980	$ 27,450
Operating profit
Interest Expense	(64)	(43)
Income Before Income Taxes	416	440
Finite Lived Intangible Assets Amortization Expense [Abstract]
Amortization of acquisition-related intangibles	48	28
Technology Solutions [Member]
Revenues
Segment Reporting Revenue From External Customers	802	759
Operating profit
Operating profit	100	64
Technology Solutions - Services [Member]
Revenues
Segment Reporting Revenue From External Customers	630	595
Technology Solutions - Software & Software Systems [Member]
Revenues
Segment Reporting Revenue From External Customers	144	135
Technology Solutions - Hardware [Member]
Revenues
Segment Reporting Revenue From External Customers	28	29
Distribution Solutions [Member]
Revenues
Segment Reporting Revenue From External Customers	29,178	26,691
Operating profit
Operating profit	475	505
Distribution Solutions Direct Distribution and services [Member]
Revenues
Segment Reporting Revenue From External Customers	20,827	18,702
Distribution Solutions - Sales to Customers' Warehouses [Member]
Revenues
Segment Reporting Revenue From External Customers	4,891	4,743
Distribution Solutions - Total U.S. Pharmaceutical Distribution & Services [Member]
Revenues
Segment Reporting Revenue From External Customers	25,718	23,445
Distribution Solutions - Canada Pharmaceutical Distribution & Services [Member]
Revenues
Segment Reporting Revenue From External Customers	2,729	2,560
Distribution Solutions - Medical - Surgical Distribution & Services
Revenues
Segment Reporting Revenue From External Customers	731	686
Reportable Segment [Member]
Operating profit
Operating profit	575	569
Corporate [Member]
Operating profit
Operating profit	$ (95)	$ (86)

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Operating profit before interest expense, income taxes and results from discontinued operations.

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Aggregate amount of intangible asset amortization recognized as expense during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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Interest and debt related expenses associated with nonoperating financing activities of the entity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21
-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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 1

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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