Material Agreements (Details) - USD ($) $ in Thousands		1 Months Ended		2 Months Ended	3 Months Ended		6 Months Ended		8 Months Ended	17 Months Ended	63 Months Ended
	Nov. 03, 2020	Nov. 30, 2020	Jun. 30, 2020	Dec. 31, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Feb. 20, 2019	Jun. 30, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues					$ 15,345	$ 21,675	$ 26,467	$ 30,440
License and royalty revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues					2,311	12,928	$ 4,672	$ 13,354
Commercial Exploitation Agreement with Indivior
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
License agreement term							7 years
Automatic renewal period of agreement							1 year
Commercial Exploitation Agreement with Indivior | Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Notice period of intent not to renew agreement							1 year
Supplemental Agreement with Indivior
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent payments receivable in the future					34,250		$ 34,250		$ 34,250		$ 34,250
Revenues										$ 40,750
Supplemental Agreement with Indivior | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent payments receivable in the future					75,000		75,000		75,000		75,000
Supplemental Agreement with Indivior Performance or Event-Based Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent payments receivable in the future					33,000		33,000		33,000		33,000
Supplemental Agreement with Indivior Additional Process Patent Rights to the Company
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Contingent payments receivable in the future					1,250		1,250		1,250		1,250
License Agreement with Sunovion Pharmaceuticals, Inc.
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues											22,000
License Agreement with Sunovion Pharmaceuticals, Inc. | License and royalty revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues						$ 8,000
License Agreement with Sunovion Pharmaceuticals, Inc Milestones
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues											17,000
License Agreement with Sunovion Pharmaceuticals, Inc Milestones | License and royalty revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues							$ 4,000
License Agreement with Sunovion Pharmaceuticals, Inc. Upfront
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues											$ 5,000
Marathon Pangolin Royalty LLC | Monetization Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from sale of future revenue	$ 40,000			$ 10,000					$ 50,000
Proceeds from debt, contingent on additional milestones		$ 75,000
Marathon Pangolin Royalty LLC | Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from sale of future revenue	$ 125,000
Agreement to Terminate CLA with KemPharm | License and royalty revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenues			$ 500		$ 2,000