Revenues, Recognition and Allowances - Adjustments to Gross Product Sales (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Gross product sales	$ 41,814	$ 40,111	$ 108,550	$ 124,801
Deduction to gross product sales:
Chargebacks and billbacks	14,573	10,739	37,285	49,103
Wholesaler fees for service	2,355	1,662	6,303	2,774
Sales discounts and other allowances	6,658	11,335	16,371	28,636
Total reduction to gross product sales	23,586	23,736	59,959	80,513
Company product sales, net	18,466	18,294	49,929	49,088
Company product sales
Deduction to gross product sales:
Company product sales, net	$ 18,228	$ 16,375	$ 48,591	$ 44,288