Total Purchase Consideration And Preliminary Purchase Price Allocation (Detail) (Magma Corporation, USD $) In Thousands, unless otherwise specified	Feb. 22, 2012
Magma Corporation
Business Acquisition [Line Items]
Cash paid	$ 543,437
Fair value of assumed equity awards allocated to purchase consideration	6,797
Total purchase consideration	550,234
Goodwill	303,487
Identifiable intangibles assets acquired	184,300
Other assets acquired	115,948
Debt and liabilities assumed	(53,501)
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 amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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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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