Accrued Liabilities - Schedule of Accrued Compensation and Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accrued compensation:
Accrued bonuses	$ 6,364	$ 11,582
Accrued paid time off	4,924	2,441
Other accrued compensation	4,006	1,997
Total accrued compensation	15,294	16,020
Accrued expenses and other current liabilities:
Accrued research and development	3,734	1,197
Accrued professional fees	2,875	1,717
Accrued property and equipment	2,514	2,892
Other accrued current liabilities	3,707	3,660
Total accrued expenses and other current liabilities	$ 12,830	$ 9,466