Goodwill and Intangible Assets - Intangible Assets by Major Asset Class (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Intangible Assets By Major Class [Line Items]
Gross	$ 264,051		$ 128,152
Accumulated Amortization	39,700		39,421
Net Book Value	224,351		88,731
Aggregate amortization expense on intangible assets	280	$ 59
Patents
Intangible Assets By Major Class [Line Items]
Gross	31,581		31,581
Accumulated Amortization	31,478		31,440
Net Book Value	$ 103		141
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	$ 15,780		7,981
Accumulated Amortization	8,222		7,981
Net Book Value	$ 7,558		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)	10 years
Trade name, trademark and trade dress and other
Intangible Assets By Major Class [Line Items]
Gross	$ 216,690		88,590
Net Book Value	$ 216,690		$ 88,590