Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Net revenue	$ 61,931	$ 62,197
U.S.
Disaggregation of Revenue [Line Items]
Net revenue	55,391	56,578
Non-US
Disaggregation of Revenue [Line Items]
Net revenue	6,540	5,619
Drug Revenues
Disaggregation of Revenue [Line Items]
Net revenue	1,076	1,136
Drug Revenues | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	835	910
Drug Revenues | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	241	226
Concentrate Products
Disaggregation of Revenue [Line Items]
Net revenue	60,855	61,061
Concentrate Products | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	54,556	55,668
Concentrate Products | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	6,299	5,393
Point-in-time | Drug Product Sales
Disaggregation of Revenue [Line Items]
Net revenue	835	910
Point-in-time | Drug Product Sales | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	835	910
Point-in-time | Drug Product Sales | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	0	0
Point-in-time | Concentrate Product Sales
Disaggregation of Revenue [Line Items]
Net revenue	58,913	59,100
Point-in-time | Concentrate Product Sales | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	52,614	53,707
Point-in-time | Concentrate Product Sales | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	6,299	5,393
Point-in-time | Concentrate Product License Fee
Disaggregation of Revenue [Line Items]
Net revenue	1,942	1,961
Point-in-time | Concentrate Product License Fee | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	1,942	1,961
Point-in-time | Concentrate Product License Fee | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	0	0
Over-time | Drug License Fee
Disaggregation of Revenue [Line Items]
Net revenue	241	226
Over-time | Drug License Fee | U.S.
Disaggregation of Revenue [Line Items]
Net revenue	0	0
Over-time | Drug License Fee | Non-US
Disaggregation of Revenue [Line Items]
Net revenue	$ 241	$ 226