Amount of liabilities incurred for defined benefit postretirement plan obligations assumed at the acquisition date.

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Amount of assets acquired at the acquisition date.

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Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred revenue expected to be recognized as such within one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary difference due within one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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-SubTopic 20

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions - Fair Value of Assets Acquired and Liabilities Assumed (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2015	Dec. 31, 2014	Jan. 02, 2015	Mar. 31, 2014	Jun. 11, 2014
Business Acquisition [Line Items]
Goodwill	$ 1,411,971us-gaap_Goodwill	$ 943,374us-gaap_Goodwill
Tripwire [Member]
Business Acquisition [Line Items]
Cash			2,364
Receivables			37,792
Inventories			603
Other current assets			2,822
Property, plant and equipment			11,113
Goodwill	477,607		477,607
Intangible assets			306,000
Other non-current assets			658
Total assets			838,959
Accounts payable			3,142
Accrued liabilities			11,546
Deferred revenue			8,000
Deferred income taxes			112,522
Other non-current liabilities			540
Total liabilities			135,750
Net assets			703,209
Grass Valley [Member]
Business Acquisition [Line Items]
Cash				9,451
Receivables				67,354
Inventories				18,593
Other current assets				4,172
Property, plant and equipment				22,460
Goodwill	131,070			131,070
Intangible assets				95,500
Other non-current assets				17,101
Total assets				365,701
Accounts payable				51,276
Accrued liabilities				62,672
Deferred revenue				14,000
Postretirement benefits				16,538
Deferred income taxes				1,827
Other non-current liabilities				1,199
Total liabilities				147,512
Net assets				218,189
Prosoft Technology, Inc. [Member]
Business Acquisition [Line Items]
Cash					2,517
Receivables					5,894
Inventories					2,731
Other current assets					240
Property, plant and equipment					1,076
Goodwill					56,379
Intangible assets					40,800
Other non-current assets					622
Total assets					110,259
Accounts payable					2,544
Accrued liabilities					2,480
Other non-current liabilities					1,132
Total liabilities					6,156
Net assets					$ 104,103