Intangible Assets - Schedule of Amortizable Purchased Intangible Assets from Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross	$ 42,520	$ 42,520
Accumulated Amortization	(11,647)	(10,752)
Accumulated Impairment	(29,749)	(29,749)
Net	1,124us-gaap_FiniteLivedIntangibleAssetsNet	2,019us-gaap_FiniteLivedIntangibleAssetsNet
Developed technologies
Finite-Lived Intangible Assets [Line Items]
Gross	26,000	26,000
Accumulated Amortization	(6,453)	(6,120)
Accumulated Impairment	(19,547)	(19,547)
Net	0	333
Trade name
Finite-Lived Intangible Assets [Line Items]
Gross	12,800	12,800
Accumulated Amortization	(3,183)	(2,665)
Accumulated Impairment	(8,582)	(8,582)
Net	1,035	1,553
Other
Finite-Lived Intangible Assets [Line Items]
Gross	3,720	3,720
Accumulated Amortization	(2,011)	(1,967)
Accumulated Impairment	(1,620)	(1,620)
Net	$ 89	$ 133

Intangible assets impaired accumulated impairment loss.

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- Definition

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

+ References

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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- Definition

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

+ References

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

+ References

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