Intangible Assets - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 1,385,115	$ 943,374
Acquisitions and purchase accounting adjustments	8,492	476,040
Translation impact	(2,135)	(34,299)
Reclassify to assets held for sale	(5,477)
Goodwill, Ending Balance	1,385,995	1,385,115
Broadcast Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	536,388	550,362
Acquisitions and purchase accounting adjustments	8,492	11,481
Translation impact	(838)	(25,455)
Reclassify to assets held for sale	0
Goodwill, Ending Balance	544,042	536,388
Enterprise Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	73,278	73,278
Acquisitions and purchase accounting adjustments	0	0
Translation impact	0	0
Reclassify to assets held for sale	0
Goodwill, Ending Balance	73,278	73,278
Industrial Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	196,719	200,053
Acquisitions and purchase accounting adjustments	0	1,614
Translation impact	80	(4,948)
Reclassify to assets held for sale	(5,477)
Goodwill, Ending Balance	191,322	196,719
Network Solutions [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	578,730	119,681
Acquisitions and purchase accounting adjustments	0	462,945
Translation impact	(1,377)	(3,896)
Reclassify to assets held for sale	0
Goodwill, Ending Balance	$ 577,353	$ 578,730

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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Amount of divestiture 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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