Acquisitions - Pro Forma Effect on Operating Results (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Grass Valley and Prosoft [Member]
Business Acquisition [Line Items]
Revenues	$ 2,401,200	$ 2,420,099
Income from continuing operations	67,956	66,874
Diluted income per share from continuing operations	$ 1.54	$ 1.49
PPC Broadband and Miranda Technologies [Member]
Business Acquisition [Line Items]
Revenues			2,163,302
Income from continuing operations			$ 78,827
Diluted income per share from continuing operations			$ 1.72

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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

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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

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