Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued Expenses
Employee compensation expenses	$ 3,910	$ 5,295
Research and development expenses	6,661	2,689
Licensing expenses	5,478	500
Restructuring expenses (Note 15)	3,112
Other	285	217
Total accrued expenses	$ 19,446	$ 8,701