Company Operations by Product, Customer and Geographic Area - Revenue by Significant Customer (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total revenues	$ 103,269	$ 173,245	$ 150,246
Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	101,423	172,841	147,222
Customer A | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	26,794	44,762	51,648
Customer B | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	25,413	37,965	39,359
Customer C | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	18,620	25,691	30,916
Customer D | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	9,653	53,342	17,728
Others | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	20,943	11,081	7,571
License revenue
Segment Reporting Information [Line Items]
Total revenues	1,846	404	3,024
License revenue | Wholesaler Customer
Segment Reporting Information [Line Items]
Total revenues	$ 1,846	$ 404	$ 3,024