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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Goodwill and Intangible Assets - Narratives (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) ReportingUnit	Jul. 01, 2016 USD ($)	Dec. 31, 2016 USD ($)	Oct. 31, 2016
Goodwill [Line Items]
Number of Reporting Units \| ReportingUnit	2
Goodwill	$ 240,570		$ 237,279
Goodwill, Impairment Loss	0	$ 0
Video [Member]
Goodwill [Line Items]
Goodwill	179,780		176,519
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount				67.00%
Cable Edge [Member]
Goodwill [Line Items]
Goodwill	$ 60,790		60,760
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount				123.00%
TVN [Member]
Goodwill [Line Items]
Goodwill			$ 41,670