Goodwill and Intangible Assets - Intangible Assets by Major Asset Class (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Intangible Assets By Major Class [Line Items]
Gross	$ 128,152		$ 128,132
Accumulated Amortization	39,409		39,350
Net Book Value	88,743		88,782
Aggregate amortization expense on intangible assets	59	$ 38
Patents
Intangible Assets By Major Class [Line Items]
Gross	31,581		31,581
Accumulated Amortization	31,428		31,389
Net Book Value	$ 153		192
Patents | Minimum
Intangible Assets By Major Class [Line Items]
Useful Life (years)	2 years
Patents | Maximum
Intangible Assets By Major Class [Line Items]
Useful Life (years)	16 years
Developed technology and other
Intangible Assets By Major Class [Line Items]
Gross	$ 7,981		7,961
Accumulated Amortization	7,981		7,961
Net Book Value	$ 0		0
Developed technology and other | Minimum
Intangible Assets By Major Class [Line Items]
Useful Life (years)	1 year
Developed technology and other | Maximum
Intangible Assets By Major Class [Line Items]
Useful Life (years)	9 years
Trade name, trademark and trade dress and other
Intangible Assets By Major Class [Line Items]
Gross	$ 88,590		88,590
Net Book Value	$ 88,590		$ 88,590