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Percentage of voting equity interests acquired in the business combination.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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Amount of deferred tax assets or liabilities for the differences between the values assigned and the tax bases of assets and liabilities in a business combination, net of any valuation allowance for deferred tax assets.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

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The useful life of all finite-lived intangible assets.

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Acquisitions (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended	6 Months Ended		6 Months Ended											6 Months Ended
	Sep. 30, 2011	Mar. 31, 2011	Sep. 30, 2011 ITKO [Member]	Sep. 30, 2011 ITKO [Member]	Aug. 31, 2011 ITKO [Member]	Sep. 30, 2011 ITKO [Member] Minimum [Member] Year	Sep. 30, 2011 ITKO [Member] Minimum [Member] Purchased software products [Member] Year	Sep. 30, 2011 ITKO [Member] Maximum [Member] Year	Sep. 30, 2011 ITKO [Member] Maximum [Member] Purchased software products [Member] Year	Sep. 30, 2011 Fiscal 2012 Acquisitions [Member]	Sep. 30, 2011 Fiscal 2012 Acquisitions [Member] Minimum [Member] Year	Sep. 30, 2011 Fiscal 2012 Acquisitions [Member] Minimum [Member] Purchased software products [Member] Year	Sep. 30, 2011 Fiscal 2012 Acquisitions [Member] Maximum [Member] Year	Sep. 30, 2011 Fiscal 2012 Acquisitions [Member] Maximum [Member] Purchased software products [Member] Year	Sep. 30, 2011 Arcot [Member]	Dec. 31, 2010 Arcot [Member]	Sep. 30, 2011 Arcot [Member] Minimum [Member] Year	Sep. 30, 2011 Arcot [Member] Maximum [Member] Year	Sep. 30, 2011 Arcot [Member] Purchased software products [Member] Year
Allocation of purchase price and estimated useful lives
Business acquisition, percentage of voting interests acquired					100.00%											100.00%
Finite-lived intangible assets			$ 6	$ 6						$ 11					$ 39
Purchase software			148	148						8					86
Goodwill			192	192						20					60
Deferred tax assets/(liabilities)			(50)	(50)						(3)					(1)
Other assets net of other liabilities assumed			21	21						3					13
Purchase Price			317	317						39					197
Cash acquired from acquisition			20
Estimated Useful Life
Finite-lived intangible assets, estimated useful life						3	5	15	7		3	5	15	7			2	5	10
Goodwill, estimated useful life				Indefinite						Indefinite					Indefinite
Acquisitions (Textual) [Abstract]
Accrued acquisition-related costs relative to amounts withheld subject to indemnification protections	$ 44	$ 77