Restricted Cash - Summary of Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash	$ 8,819	$ 2,143
Fremont, CA
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash	6,676
Cambridge, MA
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash	961	961
South San Francisco, CA
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash	816	816
Seattle, WA
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash	$ 366	$ 366