Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	$ 168,847	$ 168,847
Accumulated Amortization	(126,246)	(124,563)
Foreign Currency Translation	(26)	(257)
Intangible assets, net	42,575	44,027
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	101,200	101,200
Accumulated Amortization	(82,939)	(82,330)
Foreign Currency Translation	(142)	(272)
Intangible assets, net	18,119	18,598
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	37,251	37,251
Accumulated Amortization	(17,251)	(16,345)
Foreign Currency Translation	105	10
Intangible assets, net	20,105	20,916
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	30,396	30,396
Accumulated Amortization	(26,056)	(25,888)
Foreign Currency Translation	11	5
Intangible assets, net	$ 4,351	$ 4,513

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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