Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation, Weighted-Average Assumptions Used in Black-Scholes Option-pricing Model (Details)

v3.22.2
Stock-based Compensation, Weighted-Average Assumptions Used in Black-Scholes Option-pricing Model (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2022
Jun. 30, 2021
Jun. 30, 2022
Jun. 30, 2021
2018 Equity Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]        
Common stock available for future issuance (in shares) 0   0  
2020 Plan Evergreen Provision [Member]        
Weighted-average Assumptions Used in Black-Scholes Option-pricing Model [Abstract]        
Expected stock price volatility 96.20% 99.20% 98.80% 97.20%
Expected life of options 5 years 8 months 12 days 5 years 9 months 18 days 5 years 10 months 24 days 5 years 9 months 18 days
Expected dividend yield 0.00% 0.00% 0.00% 0.00%
Risk free interest rate 3.30% 0.90% 2.10% 0.90%
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]        
Stock options vested (in shares) 204,406 114,727 267,103 232,944
Stock options forfeited (in shares) 6,000 25,558 14,288 25,558
Common stock available for future issuance (in shares) 1,098,645   1,098,645  
Unrecognized stock-based compensation cost $ 3.2   $ 3.2  
Weighted average period to recognized stock-based compensation     1 year 4 months 24 days  
Inducement Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]        
Common stock available for future issuance (in shares) 1,098,645   1,098,645