Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating results:
Total revenues	$ 49,299	$ 53,889	$ 51,984	$ 61,902	$ 52,912	$ 44,921	$ 45,087	$ 47,435	$ 217,074	$ 190,355	$ 159,289
Cost of product, licensing and other revenues	38,000	34,261	30,973	32,340	31,814	30,456	25,732	24,843	135,574	112,845	78,396
Gross profit	11,299	19,628	21,011	29,562	21,098	14,465	19,355	22,592
Other costs and expenses	49,012	46,283	43,526	39,167	38,446	35,206	34,827	28,869
Interest expense and other (expense) income, net	(155)	741	(641)	920	(5,612)	3,111	(4,209)	(3,727)
Income tax expense	(39)	(103)							(142)
Net loss	$ (37,907)	$ (26,017)	$ (23,156)	$ (8,685)	$ (22,960)	$ (17,630)	$ (19,681)	$ (10,004)	$ (95,765)	$ (70,275)	$ (5,152)
Per share data:
Basic and diluted net loss per share (in dollars per share)	$ (0.72)	$ (0.50)	$ (0.46)	$ (0.17)	$ (0.47)	$ (0.39)	$ (3.58)	$ (1.89)	$ (1.86)	$ (2.68)	$ (1.07)