Goodwill and Intangible Assets - Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	$ 163,737	$ 124,887
Accumulated Amortization	(117,799)	(112,854)
Foreign Currency Translation	451	1,057
Intangible assets, net	46,389us-gaap_FiniteLivedIntangibleAssetsNet	13,090us-gaap_FiniteLivedIntangibleAssetsNet
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	100,380	84,680
Accumulated Amortization	(79,875)	(78,072)
Foreign Currency Translation	135	519
Intangible assets, net	20,640	7,127
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	35,821	14,571
Accumulated Amortization	(12,634)	(9,831)
Foreign Currency Translation	280	454
Intangible assets, net	23,467	5,194
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	27,536	25,636
Accumulated Amortization	(25,290)	(24,951)
Foreign Currency Translation	36	84
Intangible assets, net	$ 2,282	$ 769

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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