Condensed Consolidated Statements of Earnings - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues
Total revenues	$ 94,976	$ 85,474
Costs and expenses
Cost of goods sold	4,152	3,684
Research and development	18,937	15,394
Selling, general and administrative	42,875	40,968
Total costs and expenses	65,964	60,046
Operating earnings	29,012	25,428
Other income (expense)
Interest expense	(5,755)	(5,870)
Interest income, net	5,777	4,681
Total other income (expense)	22	(1,189)
Earnings before income taxes	29,034	24,239
Income tax expense	7,516	5,899
Net earnings	$ 21,518	$ 18,340
Earnings per share
Basic (in dollars per share)	$ 0.41	$ 0.35
Diluted (in dollars per share)	$ 0.40	$ 0.34
Weighted-average shares outstanding
Basic (in shares)	52,534,787	52,336,443
Diluted (in shares)	53,581,051	53,985,385
Net product sales
Revenues
Total revenues	$ 92,490	$ 83,099
Royalty revenues
Revenues
Total revenues	$ 2,486	$ 2,375