Segment Information Segment Information 3 (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended	3 Months Ended
Sep. 30, 2012 Enterprise Solutions [Member]	Sep. 30, 2011 Restructuring Activity Fiscal Plan 2012 [Member] Mainframe Solutions [Member]	Sep. 30, 2011 Restructuring Activity Fiscal Plan 2012 [Member] Enterprise Solutions [Member]	Sep. 30, 2011 Restructuring Activity Fiscal Plan 2012 [Member] Services [Member]
Segment Reporting [Line Items]
Intellectual Property Assets Transaction Value	$ 35
Severance Costs		$ 23	$ 20	$ 1

The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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+ Details