Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net revenues	$ 32,200	$ 27,484
Cost of product sales	15,219	13,505
Operating expenses:
Selling, general and administrative	26,035	23,689
Research and development	6,934	11,766
Total operating expenses	32,969	35,455
Loss from operations	(15,988)	(21,476)
Interest expense, net	(15,510)	(10,886)
Other expense, net	(560)	(307)
Loss before provision for income taxes	(32,058)	(32,669)
Benefit from (Provision for) income taxes	211	(159)
Net loss	$ (31,847)	$ (32,828)
Net loss per common share—basic and diluted (in usd per share)	$ (1.67)	$ (1.76)
Weighted-average shares outstanding—basic and diluted (in shares)	19,022	18,703