Acquisitions - Pro Forma Effect on Operating Results (Detail) (Grass Valley And Prosoft [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Grass Valley And Prosoft [Member]
Business Acquisition [Line Items]
Revenues	$ 612,617	$ 609,760	$ 1,790,876	$ 1,851,860
Income from continuing operations	$ 36,036	$ 70,399	$ 49,645	$ 81,707
Diluted income per share from continuing operations	$ 0.82	$ 1.58	$ 1.12	$ 1.82

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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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