Consolidated Statements of Earnings - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue
Total revenue	$ 102,996	$ 80,398	$ 292,963	$ 213,803
Costs and expenses
Cost of product sales	4,207	4,251	11,168	11,060
Research and development	20,422	12,980	59,368	33,405
Selling, general and administrative	40,892	40,825	117,838	104,141
Total costs and expenses	65,521	58,056	188,374	148,606
Operating earnings	37,475	22,342	104,589	65,197
Other income (expense)
Interest income	4,461	814	9,331	2,002
Interest expense	(4,374)		(9,415)	(148)
Interest expense-nonrecourse liability related to sale of future royalties	(1,191)	(155)	(3,096)	(1,274)
Changes in fair value of derivative liabilities				76
Loss on extinguishment of debt		(91)		(295)
Total other income (expense)	(1,104)	568	(3,180)	361
Earnings before income taxes	36,371	22,910	101,409	65,558
Income tax expense	8,360	6,949	16,309	21,932
Net earnings	$ 28,011	$ 15,961	$ 85,100	$ 43,626
Earnings per share:
Basic (in dollars per share)	$ 0.54	$ 0.31	$ 1.64	$ 0.86
Diluted (in dollars per share)	$ 0.52	$ 0.29	$ 1.57	$ 0.82
Weighted-average number of common shares outstanding:
Basic (in shares)	52,227,630	51,046,375	51,897,240	50,583,726
Diluted (in shares)	54,239,847	53,628,389	54,098,330	53,227,433
Product
Revenue
Total revenue	$ 100,227	$ 78,066	$ 286,377	$ 207,763
Royalty
Revenue
Total revenue	$ 2,769	2,010	5,836	4,338
Licensing
Revenue
Total revenue		$ 322	$ 750	$ 1,702