Revenue by Product - Summary of Revenue (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)
Segment Reporting [Abstract]
Number of operating segments (in segments) | segment			1
Segment Reporting Information [Line Items]
Total revenues	$ 17,554	$ 29,230	$ 33,991	$ 62,523
Bloxiverz
Segment Reporting Information [Line Items]
Total revenues	2,358	5,544	4,926	13,035
Vazculep
Segment Reporting Information [Line Items]
Total revenues	9,410	11,377	18,883	24,338
Akovaz
Segment Reporting Information [Line Items]
Total revenues	5,946	11,875	9,738	22,092
Other
Segment Reporting Information [Line Items]
Total revenues	(160)	320	444	2,812
Product sales
Segment Reporting Information [Line Items]
Total revenues	17,554	29,116	33,991	62,277
License revenue
Segment Reporting Information [Line Items]
Total revenues	$ 0	$ 114	$ 0	$ 246