Liability Related to Sale of Future Royalties - Rollforward of Liability Related to Sale of Future Royalties (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Contractual Arrangement, Royalties Agreement, Liability, Noncurrent [Roll Forward]
Liability related to sale of future royalties, net beginning balance at December 31, 2021	$ 53,079
MTPC royalties payable	(1,195)
Non-cash interest expense recognized	6,352	$ 6,779
Liability related to sale of future royalties, net — ending balance	$ 58,236