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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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

No definition available.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ 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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Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($)		12 Months Ended
	Apr. 29, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		$ 565,698,000	$ 573,353,000
Impairment Charges		(1,511,000)	0	$ 0
Accumulated Amortization		(199,619,000)	(160,813,000)
Foreign Currency Translation		1,830,000	(4,536,000)
Intangible assets, net		366,398,000	408,004,000
Acquired intangible assets	$ 404,506,000
Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			404,506,000
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		172,431,000	176,586,000
Impairment Charges		(105,000)
Accumulated Amortization		(115,371,000)	(97,707,000)
Foreign Currency Translation		333,000	(1,068,000)
Intangible assets, net		57,288,000	77,811,000
Completed Technology [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			75,386,000
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		282,744,000	285,044,000
Impairment Charges		(1,406,000)
Accumulated Amortization		(45,518,000)	(29,709,000)
Foreign Currency Translation		1,571,000	(3,404,000)
Intangible assets, net		237,391,000	251,931,000
Customer Relationships [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 247,793,000		247,793,000
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross		110,523,000	111,723,000
Accumulated Amortization		(38,730,000)	(33,397,000)
Foreign Currency Translation		(74,000)	(64,000)
Intangible assets, net		$ 71,719,000	78,262,000
Patents, Trademarks, Trade Names and Other [Member] \| Newport [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets			$ 81,327,000