Accrued Expenses & Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accrued expenses and other current liabilities:
Accrued compensation and benefits	$ 15,207	$ 11,169
Accrued consulting and professional fees	2,645	3,810
Accrued research and development	2,222	8,734
Accrued revenue reserves	66,552	38,450
Accrued other	4,097	3,213
Total accrued expenses and other current liabilities	$ 90,723	$ 65,376