Sale of Future Revenue (Details) - USD ($) $ in Thousands			1 Months Ended	2 Months Ended	3 Months Ended			9 Months Ended		11 Months Ended
	Nov. 03, 2020	Apr. 01, 2016	Nov. 30, 2020	Dec. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Payments for loan acquisition costs								$ 2,909
Revenues					$ 13,287	$ 8,260		39,754	$ 38,700
Royalty
Disaggregation of Revenue [Line Items]
Revenues								(1,077)
Marathon Pangolin Royalty LLC | Maximum
Disaggregation of Revenue [Line Items]
Proceeds from sale of future revenue	$ 125,000
License Agreement with Sunovion Pharmaceuticals, Inc.
Disaggregation of Revenue [Line Items]
Revenues		$ 22,000
Minimum annual royalty receivable					$ 1,000		$ 1,000	$ 1,000		$ 1,000
Guaranteed royalty period							8 years	8 years
License Agreement with Sunovion Pharmaceuticals, Inc. | Royalty
Disaggregation of Revenue [Line Items]
Revenues							$ 8,000
Monetization Agreement
Disaggregation of Revenue [Line Items]
Effective annual interest rate	24.90%
Monetization Agreement | Marathon Pangolin Royalty LLC
Disaggregation of Revenue [Line Items]
Proceeds from sale of future revenue	$ 40,000			$ 10,000						$ 50,000
Proceeds from debt, contingent on additional milestones			$ 75,000