Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued compensation	$ 10,920	$ 15,161
Accrued variable consideration	14,239	5,025
Accrued professional fees	5,069	3,183
Accrued interest on convertible notes	4,200	1,369
Accrued other	48	52
Total other accrued liabilities	$ 34,476	$ 24,790