Acquisitions - Pro Forma Effect on Operating Results (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Tripwire [Member]
Business Acquisition [Line Items]
Revenues	$ 563,371	$ 499,491
Income (loss) from continuing operations	(215)	1,927
Diluted income (loss) per share from continuing operations	$ (0.01)	$ 0.04
Grass Valley and Prosoft [Member]
Business Acquisition [Line Items]
Revenues		563,624
Income (loss) from continuing operations		$ 2,297
Diluted income (loss) per share from continuing operations		$ 0.05

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The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, per diluted share of common stock for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

+ Details

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- Definition

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

+ Details

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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