Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue:
Total revenue	$ 171,546	$ 187,802	$ 195,892
Operating expenses:
Cost, Product and Service [Extensible List]	Product sales, net	Product sales, net	Product sales, net
Cost of product sales	$ 31,528	$ 33,647	$ 47,891
Cost of royalty revenue	10,652	11,818	13,006
Research and development	51,275	30,785	36,810
Selling, general and administrative	75,322	78,598	76,370
Total operating expenses	168,777	154,848	174,077
Income from operations	2,769	32,954	21,815
Interest income	560	562	2,169
Interest expense	(1,635)	(2,577)	(2,686)
Other (expense) income	(6,242)	(8,262)	700
Total other (expense) income, net	(7,317)	(10,277)	183
(Loss) income before income tax provision	(4,548)	22,677	21,998
Income tax provision	(4,079)	(10,688)	(7,685)
Net (loss) income	$ (8,627)	$ 11,989	$ 14,313
(Loss) Earnings per common share:
Basic (in dollars per share)	$ (0.66)	$ 0.89	$ 1.04
Diluted (in dollars per share)	$ (0.66)	$ 0.87	$ 1.01
Weighted average number of common shares outstanding:
Basic (in shares)	13,051,095	13,481,525	13,754,516
Diluted (in shares)	13,051,095	13,771,393	14,138,733
Product sales, net
Revenue:
Total revenue	$ 65,023	$ 72,323	$ 73,989
Royalty revenue
Revenue:
Total revenue	106,523	110,479	112,903
License and other revenue
Revenue:
Total revenue	$ 0	$ 5,000	$ 9,000