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Grant Revenue - Additional Information (Details) - Grant - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Disaggregation Of Revenue [Line Items]        
Recognized grant revenue $ 0   $ 0 $ 200,000
Maximum        
Disaggregation Of Revenue [Line Items]        
Recognized grant revenue   $ 100,000