Consolidated Statements of (Loss) Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues:
Total revenues	$ 103,269	$ 173,245	$ 150,246
Operating expenses:
Cost of products	17,516	16,301	13,248
Research and development expenses	39,329	33,418	34,611
Selling, general and administrative expenses	100,359	58,860	44,179
Intangible asset amortization	6,619	3,659	13,888
(Gain) loss - changes in fair value of related party contingent consideration	(22,731)	(31,040)	49,285
Impairment of intangible asset	66,087	0	0
Restructuring costs	1,016	2,542	0
Total operating expenses	208,195	83,740	155,211
Operating (loss) income	(104,926)	89,505	(4,965)
Investment and other income, net	452	2,136	2,758
Interest expense	(10,622)	(1,052)	(963)
Other income (expense) - changes in fair value of related party payable	1,899	2,071	(6,548)
(Loss) income before income taxes	(113,197)	92,660	(9,718)
Income tax (benefit) provision	(17,893)	24,389	31,558
Net (loss) income	$ (95,304)	$ 68,271	$ (41,276)
Earnings (loss) per share
Net income (loss) per share - basic (in usd per share)	$ (2.55)	$ 1.69	$ (1.00)
Net income (loss) per share - diluted (in usd per share)	$ (2.55)	$ 1.63	$ (1.00)
Weighted average number of shares outstanding
Weighted average number of shares outstanding - basic (in shares)	37,325	40,465	41,248
Weighted average number of shares outstanding - diluted (in shares)	37,325	41,765	41,248
Product sales
Revenues:
Total revenues	$ 101,423	$ 172,841	$ 147,222
License revenue
Revenues:
Total revenues	$ 1,846	$ 404	$ 3,024