Goodwill and Intangible Assets - Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	$ 168,847	$ 163,737
Accumulated Amortization	(119,470)	(117,799)
Foreign Currency Translation	176	451
Intangible assets, net	49,553us-gaap_FiniteLivedIntangibleAssetsNet	46,389us-gaap_FiniteLivedIntangibleAssetsNet
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	101,200	100,380
Accumulated Amortization	(80,477)	(79,875)
Foreign Currency Translation	(78)	135
Intangible assets, net	20,645	20,640
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	37,251	35,821
Accumulated Amortization	(13,610)	(12,634)
Foreign Currency Translation	228	280
Intangible assets, net	23,869	23,467
Patents, Trademarks, Trade Names and Other [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, Gross	30,396	27,536
Accumulated Amortization	(25,383)	(25,290)
Foreign Currency Translation	26	36
Intangible assets, net	$ 5,039	$ 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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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for foreign currency translation adjustments.

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