Goodwill, Capitalized Software and Other Intangible Assets 3 (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Dec. 31, 2014
Goodwill activity by segment
Balance at March 31, 2014	$ 5,922us-gaap_Goodwill
Divestiture	(109)
Foreign currency translation adjustment	(4)us-gaap_GoodwillTranslationAdjustments
Balance at December 31, 2014	5,809us-gaap_Goodwill
Mainframe Solutions [Member]
Goodwill activity by segment
Balance at March 31, 2014	4,178
Divestiture	0
Foreign currency translation adjustment	0
Balance at December 31, 2014	4,178
Enterprise Solutions [Member]
Goodwill activity by segment
Balance at March 31, 2014	1,663
Divestiture	(109)
Foreign currency translation adjustment	(4)
Balance at December 31, 2014	1,550
Services [Member]
Goodwill activity by segment
Balance at March 31, 2014	81
Divestiture	0
Foreign currency translation adjustment	0
Balance at December 31, 2014	$ 81

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=14024403&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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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

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

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-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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+ References

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

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