Total Purchase Consideration and Preliminary Purchase Price Allocation (Detail) (USD $) In Thousands, unless otherwise specified	Oct. 31, 2012	Oct. 01, 2012
SpringSoft Corporation
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Cash paid	$ 373,519	$ 373,519
Fair value of shares to be acquired through a follow-on merger	34,054
Fair value of assumed equity awards allocated to purchase consideration	9,383
Total purchase consideration	416,956	416,956
Goodwill	247,482
Identifiable intangibles assets acquired	108,867
Cash and other assets acquired	137,222
Liabilities assumed	(76,615)
Total purchase allocation	416,956
Magma Corporation
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Cash paid	543,437
Fair value of assumed equity awards allocated to purchase consideration	6,797
Total purchase consideration	550,234
Goodwill	316,263
Identifiable intangibles assets acquired	184,300
Cash and other assets acquired	116,265
Liabilities assumed	(66,594)
Total purchase allocation	$ 550,234

Business Combination Cost Of Acquired Entity Equity Interests Issued And Issuable Fair Value Method

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Amount of cash paid to acquire the entity.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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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 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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Amount of acquisition cost of a business combination allocated to other assets not separately disclosed in the balance sheet.

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