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Stock-Based Compensation Expense - Additional Information (Details) - USD ($)
1 Months Ended 12 Months Ended
Jan. 31, 2021
Apr. 30, 2020
Feb. 29, 2016
Dec. 31, 2021
Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares granted       428,500  
Shares of common stock reserved for future issuances       3,545,808  
Stock-based compensation expense       $ 2,770,000 $ 1,813,000
Weighted-average fair value of options granted to employees, directors and consultants       $ 6.89 $ 9.66
Aggregate intrinsic value of stock options exercised       $ 300,000 $ 27,000
Unrecognized stock-based compensation expense relating to unvested stock options       $ 5,700,000  
Unvested stock options expected to be recognized over a weighted-average period       2 years 7 months 6 days  
Milestone-based Awards          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Stock-based compensation expense       $ 0 $ 0
Revenue Based Milestone Awards [Member]          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Unrecognized stock-based compensation expense relating to unvested stock options       $ 36,000  
Minimum          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Vesting period       4 years  
Maximum          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Stock option expiration period       10 years  
2005 and 2016 Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares granted     0    
2020 Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Shares of common stock reserved for future issuances   2,100,000      
Maximum number of common shares issued   8,800,000      
Percentage of common shares increase automatically in each year   4.00%      
Increase in Shares available for grant 517,295        
Number of shares available for future grant       1,668,286  
2020 ESPP          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Shares of common stock reserved for future issuances   150,000      
Maximum number of common shares issued   987,500      
Annual increase in number of shares available for issuance as percentage of outstanding shares common stock on final day of immediately preceding fiscal year   0.50%      
Purchase price of shares as percentage lower of fair market value of common stock   85.00%