Accrued Liabilities - Schedule of Accrued Compensation and Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued compensation:
Accrued paid time off	$ 4,561	$ 2,441
Accrued bonuses	3,194	11,582
Other accrued compensation	3,056	1,997
Total accrued compensation	10,811	16,020
Accrued expenses and other current liabilities:
Accrued research and development	3,121	1,197
Accrued property and equipment	2,594	2,892
Accrued professional fees	2,051	1,717
Other	3,405	3,660
Total accrued expenses and other current liabilities	$ 11,171	$ 9,466