Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accrued Expenses
Employee compensation expenses	$ 2,885	$ 4,389
Research and development expenses	2,771	1,278
Litigation settlements (see Note 16)		2,650
Other	1,915	1,734
Total accrued expenses	$ 7,571	$ 10,051