Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Acquired Intangible Assets by Major Class [Line Items]
Trademarks, net	$ 300	$ 300
Amortized Intangible Assets, Gross Carrying Amount	60,340	60,340
Amortized Intangible Assets, Accumulated Amortization	(39,317)	(38,150)
Amortized Intangible Assets, Net Amount	$ 21,023	22,190
Licenses
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	5 years 9 months 22 days
Amortized Intangible Assets, Gross Carrying Amount	$ 20,130	20,130
Amortized Intangible Assets, Accumulated Amortization	(18,900)	(18,620)
Amortized Intangible Assets, Net Amount	$ 1,230	1,510
Product Lines
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	10 years 4 months 9 days
Amortized Intangible Assets, Gross Carrying Amount	$ 33,858	33,858
Amortized Intangible Assets, Accumulated Amortization	(14,065)	(13,178)
Amortized Intangible Assets, Net Amount	$ 19,793	20,680
Customer relationships
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	4 years 10 months 25 days
Amortized Intangible Assets, Gross Carrying Amount	$ 3,152	3,152
Amortized Intangible Assets, Accumulated Amortization	$ (3,152)	(3,152)
Trade Name
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	5 years
Amortized Intangible Assets, Gross Carrying Amount	$ 3,000	3,000
Amortized Intangible Assets, Accumulated Amortization	$ (3,000)	(3,000)
Non-compete/Employment contracts
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	5 years
Amortized Intangible Assets, Gross Carrying Amount	$ 200	200
Amortized Intangible Assets, Accumulated Amortization	$ (200)	$ (200)