Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
Apr. 29, 2016	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		$ 573,353	$ 573,353
Impairment Charges		(1,511)
Accumulated Amortization		(196,347)	(160,813)
Foreign Currency Translation		839	(4,536)
Intangible assets, net		376,334	408,004
Acquired intangible assets	$ 404,506
Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			404,506
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		176,586	176,586
Impairment Charges		(105)
Accumulated Amortization		(114,095)	(97,707)
Foreign Currency Translation		49	(1,068)
Intangible assets, net		62,435	77,811
Completed Technology [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			75,386
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		285,044	285,044
Impairment Charges		(1,406)
Accumulated Amortization		(43,397)	(29,709)
Foreign Currency Translation		832	(3,404)
Intangible assets, net		241,073	251,931
Customer Relationships [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 247,793		247,793
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		111,723	111,723
Accumulated Amortization		(38,855)	(33,397)
Foreign Currency Translation		(42)	(64)
Intangible assets, net		$ 72,826	78,262
Patents, Trademarks, Trade Names and Other [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			$ 81,327

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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