Revenues, Recognition and Allowances - Adjustments to Gross Product Sales (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Gross product sales									$ 156,301	$ 158,278
Reduction to gross product sales:
Chargebacks and billbacks									60,008	60,770
Wholesaler fees for service									9,000	5,503
Sales discounts and other allowances									23,002	32,414
Total reduction to gross product sales									92,010	98,687
Total product sales, net	$ 15,967	$ 18,466	$ 18,341	$ 13,122	$ 16,777	$ 18,294	$ 16,249	$ 14,545	65,896	65,865
Company Product
Reduction to gross product sales:
Total product sales, net									$ 64,291	$ 59,591