Goodwill and Intangible Assets, Net (Changes In The Carrying Amount Of Goodwill) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Goodwill [Line Items]
Goodwill, beginning balance	$ 9,927us-gaap_Goodwill	$ 6,405us-gaap_Goodwill
Goodwill acquired	93us-gaap_GoodwillAcquiredDuringPeriod	3,649us-gaap_GoodwillAcquiredDuringPeriod
Amount reclassified to assets held-for-sale	(15)	(128)
Acquisition accounting, transfers and other adjustments	625	1
Foreign currency translation adjustments, net	(813)us-gaap_GoodwillTranslationAdjustments	0us-gaap_GoodwillTranslationAdjustments
Goodwill, ending balance	9,817us-gaap_Goodwill	9,927us-gaap_Goodwill
Distribution Solutions [Member]
Goodwill [Line Items]
Goodwill, beginning balance	8,078	4,413
Goodwill acquired	93	3,649
Amount reclassified to assets held-for-sale	(14)	(1)
Acquisition accounting, transfers and other adjustments	625	13
Foreign currency translation adjustments, net	(788)	4
Goodwill, ending balance	7,994	8,078
Technology Solutions [Member]
Goodwill [Line Items]
Goodwill, beginning balance	1,849	1,992
Goodwill acquired	0	0
Amount reclassified to assets held-for-sale	(1)	(127)
Acquisition accounting, transfers and other adjustments	0	(12)
Foreign currency translation adjustments, net	(25)	(4)
Goodwill, ending balance	$ 1,823	$ 1,849

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

The increase (decrease) during the period in book value of long-lived assets that the reporting entity plans to sell within one year (or one business cycle).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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