Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Acquired Intangible Assets by Major Class [Line Items]
Trademarks, net	$ 2,308	$ 2,308	[1]
Deferred Costs, Net Amount	4,372	5,834
Amortized Intangible Assets, Gross Carrying Amount	76,775	81,375
Amortized Intangible Assets, Accumulated Amortization	(41,222)	(39,190)
Amortized Intangible Assets, Net Amount	$ 35,553	42,185	[1]
4.50% Convertible senior notes
Acquired Intangible Assets by Major Class [Line Items]
Deferred Costs, Weighted Useful Lives (Years)	3 years 26 days
Deferred Costs, Gross Carrying Amount	$ 1,865	1,865
Deferred Costs, Accumulated Amortization	(1,463)	(1,048)
Deferred Costs, Net Amount	402	817
Licenses
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 20,130	24,930
Weighted Useful Lives (Years)	5 years 9 months 22 days
Amortized Intangible Assets, Accumulated Amortization	$ (16,942)	(20,436)
Amortized Intangible Assets, Net Amount	3,188	4,494
Product Lines
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 50,293	50,093
Weighted Useful Lives (Years)	7 years 6 months
Amortized Intangible Assets, Accumulated Amortization	$ (18,993)	(14,376)
Amortized Intangible Assets, Net Amount	31,300	35,717
Customer relationships
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 3,152	3,152
Weighted Useful Lives (Years)	4 years 10 months 24 days
Amortized Intangible Assets, Accumulated Amortization	$ (2,620)	(2,195)
Amortized Intangible Assets, Net Amount	532	957
Trade Name
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 3,000	3,000
Weighted Useful Lives (Years)	5 years
Amortized Intangible Assets, Accumulated Amortization	$ (2,500)	(2,050)
Amortized Intangible Assets, Net Amount	500	950
Non-compete agreements
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 200	200
Weighted Useful Lives (Years)	5 years
Amortized Intangible Assets, Accumulated Amortization	$ (167)	(133)
Amortized Intangible Assets, Net Amount	$ 33	$ 67

[1] Derived from audited financial statements