Balance Sheet Accounts and Supplemental Disclosures - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheets Accounts And Supplemental Disclosures [Abstract]
Accrued compensation	$ 6,453	$ 12,194
Accrued interest, current	3,594	1,094
Operating lease liabilities, current	3,518	3,633
Accrued professional service fees	2,349	2,823
Accrued other	733	742
Accrued in process research and development	215	225
Total accrued expenses	$ 16,862	$ 20,711