Intangible Assets - Changes in Carrying Amount of Trademarks (Details) - Trademarks [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Indefinite-lived Intangible Assets [Roll Forward]
Trademarks, Beginning Balance	$ 121,972	$ 129,671
Translation impact	3,987	(4,794)
Reclassify to assets held for sale	(33,201)	(2,905)
Trademarks, Ending Balance	92,758	121,972
Broadcast Solutions [Member]
Indefinite-lived Intangible Assets [Roll Forward]
Trademarks, Beginning Balance	76,287	80,922
Translation impact	2,727	(4,635)
Reclassify to assets held for sale	0	0
Trademarks, Ending Balance	79,014	76,287
Enterprise Solutions [Member]
Indefinite-lived Intangible Assets [Roll Forward]
Trademarks, Beginning Balance	4,063	4,063
Translation impact	0	0
Reclassify to assets held for sale	0	0
Trademarks, Ending Balance	4,063	4,063
Industrial Solutions [Member]
Indefinite-lived Intangible Assets [Roll Forward]
Trademarks, Beginning Balance	6,225	9,090
Translation impact	602	40
Reclassify to assets held for sale	(2,201)	(2,905)
Trademarks, Ending Balance	4,626	6,225
Network Solutions [Member]
Indefinite-lived Intangible Assets [Roll Forward]
Trademarks, Beginning Balance	35,397	35,596
Translation impact	658	(199)
Reclassify to assets held for sale	(31,000)	0
Trademarks, Ending Balance	$ 5,055	$ 35,397

Amount of foreign currency translation gain (loss) which increases (decreases) an asset, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of divestiture of an asset lacking physical substance and having a projected indefinite period of benefit to fair value. Excludes financial assets and goodwill.

+ References

No definition available.

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- Definition

Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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