Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	$ 168,847	$ 163,737
Accumulated Amortization	(122,870)	(117,799)
Foreign Currency Translation	(330)	451
Intangible assets, net	45,647	46,389
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	101,200	100,380
Accumulated Amortization	(81,715)	(79,875)
Foreign Currency Translation	(286)	135
Intangible assets, net	19,199	20,640
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	37,251	35,821
Accumulated Amortization	(15,435)	(12,634)
Foreign Currency Translation	(49)	280
Intangible assets, net	21,767	23,467
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	30,396	27,536
Accumulated Amortization	(25,720)	(25,290)
Foreign Currency Translation	5	36
Intangible assets, net	$ 4,681	$ 2,282

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=26713463&loc=d3e16323-109275

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