Long-Lived Assets 5 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Goodwill activity by segment
Balance at beginning of year	$ 5,922us-gaap_Goodwill	$ 5,864us-gaap_Goodwill
Acquisitions		55us-gaap_GoodwillAcquiredDuringPeriod
Divestitures	(109)
Foreign currency translation adjustment	(7)us-gaap_GoodwillTranslationAdjustments	3us-gaap_GoodwillTranslationAdjustments
Balance at end of year	5,806us-gaap_Goodwill	5,922us-gaap_Goodwill
Mainframe Solutions
Goodwill activity by segment
Balance at beginning of year	4,178	4,178
Acquisitions		0
Divestitures	0
Foreign currency translation adjustment	0	0
Balance at end of year	4,178	4,178
Enterprise Solutions
Goodwill activity by segment
Balance at beginning of year	1,663	1,605
Acquisitions		55
Divestitures	(109)
Foreign currency translation adjustment	(7)	3
Balance at end of year	1,547	1,663
Services
Goodwill activity by segment
Balance at beginning of year	81	81
Acquisitions		0
Divestitures	0
Foreign currency translation adjustment	0	0
Balance at end of year	$ 81	$ 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

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-SubTopic 20

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