Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accrued Expenses and Other Current Liabilities
Research and development costs	$ 12,164	$ 17,480
Professional fees	3,494	2,163
Payroll related	3,131	8,371
Royalties	4,866	791
Other	1,544	1,279
Accrued expenses and other current liabilities	$ 25,199	$ 30,084