Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

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.

+ References

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+ Details

Segment and Geographic Information 3 (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2012 Country Customer	Mar. 31, 2011 Customer	Mar. 31, 2010 Customer
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Carrying amount of goodwill	$ 5,856	$ 5,686	$ 5,605
Wholly-owned subsidiaries in number of foreign countries	47
Segment and Geographic Information (Textual) [Abstract]
Customer accounted for 10% or more of total revenue	0	0	0
Mainframe Solutions [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Carrying amount of goodwill	4,179
Mainframe Solutions [Member] \| Restructuring Activity Fiscal Plan 2012 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs	22
Mainframe Solutions [Member] \| Restructuring Activity Fiscal Plan 2010 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs			23
Enterprise Solutions [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Carrying amount of goodwill	1,596
Enterprise Solutions [Member] \| Restructuring Activity Fiscal Plan 2012 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs	19
Enterprise Solutions [Member] \| Restructuring Activity Fiscal Plan 2010 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs			23
Services [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Carrying amount of goodwill	81
Services [Member] \| Restructuring Activity Fiscal Plan 2012 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs	1
Services [Member] \| Restructuring Activity Fiscal Plan 2010 [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Severance costs			$ 2
North America [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Wholly-owned subsidiaries in number of foreign countries	4
Europe [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Wholly-owned subsidiaries in number of foreign countries	21
Asia/Pacific [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Wholly-owned subsidiaries in number of foreign countries	14
South America [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Wholly-owned subsidiaries in number of foreign countries	7
Africa [Member]
Schedule of Revenues from External Customers and Long Lived Assets (Textual) [Abstract]
Wholly-owned subsidiaries in number of foreign countries	1