Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue
Net product sales	$ 73,328	$ 50,335	$ 129,697	$ 93,360
Royalty revenue	1,179	1,205	2,328	2,324
Licensing revenue	1,322	86	1,380	135
Total revenue	75,829	51,626	133,405	95,819
Costs and expenses
Cost of product sales	3,861	2,751	6,809	4,786
Research and development	10,823	11,109	20,425	21,671
Selling, general and administrative	35,078	26,121	63,316	51,281
Total costs and expenses	49,762	39,981	90,550	77,738
Operating income	26,067	11,645	42,855	18,081
Other income (expense)
Interest income	656	365	1,187	693
Interest expense	(58)	(196)	(147)	(375)
Interest expense-nonrecourse liability related to sale of future royalties	(160)	(1,281)	(1,119)	(2,560)
Changes in fair value of derivative liabilities	23	123	76	224
Loss on extinguishment of debt	(103)		(204)	(382)
Total other income (expense)	358	(989)	(207)	(2,400)
Earnings before income taxes	26,425	10,656	42,648	15,681
Income tax expense	9,057	405	14,983	605
Net income	$ 17,368	$ 10,251	$ 27,665	$ 15,076
Earnings per share:
Basic (in dollars per share)	$ 0.34	$ 0.21	$ 0.55	$ 0.31
Diluted (in dollars per share)	$ 0.32	$ 0.18	$ 0.52	$ 0.28
Weighted-average number of common shares outstanding:
Basic (in shares)	50,530,968	49,427,825	50,345,830	49,333,962
Diluted (in shares)	53,223,714	51,745,342	53,026,323	51,484,686