Annual report pursuant to Section 13 and 15(d)

Stock-based Compensation, Stock Option Plan Activity (Details)

v3.24.0.1
Stock-based Compensation, Stock Option Plan Activity (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Nov. 01, 2023
Nov. 30, 2020
Dec. 31, 2019
Stock Options [Abstract]            
Stock-based compensation $ 3,510,000 $ 1,807,000        
Inducement Plan [Member]            
Stock Options [Abstract]            
Common stock reserved for issuance (in shares)       2,325,258    
2020 Equity Incentive Plan [Member]            
Stock Options [Abstract]            
Common stock reserved for issuance (in shares)         1,000,000  
Percentage of common stock shares outstanding 5.00%          
2020 Equity Incentive Plan [Member] | Maximum [Member]            
Stock Options [Abstract]            
Common stock reserved for issuance (in shares)         70,325  
Period of shares reserved under plan 10 years          
2018 Equity Incentive Plan [Member]            
Stock Options [Abstract]            
Common stock reserved for issuance (in shares) 0         1,175,000
Weighted Average Exercise Price [Abstract]            
Aggregate intrinsic value, outstanding $ 70,000 $ 59,000        
Weighted average fair value per share of options granted (in dollars per share) $ 2.41 $ 3.29        
2018 Equity Incentive Plan [Member] | Former Chief Executive Officer [Member]            
Stock Options [Abstract]            
Stock-based compensation $ 400,000          
2018 Equity Incentive Plan [Member] | Minimum [Member]            
Stock Options [Abstract]            
Vesting period 5 months          
2018 Equity Incentive Plan [Member] | Maximum [Member]            
Stock Options [Abstract]            
Vesting period 48 months          
Stock Options [Member] | 2018 Equity Incentive Plan [Member]            
Stock Options [Abstract]            
Stock-based compensation $ 2,500,000 $ 1,700,000        
Number of Options [Roll Forward]            
Outstanding, beginning balance (in shares) 2,936,044 2,096,836        
Granted (in shares) 1,768,116 893,305        
Exercised (in shares) (27,469) (24,309)        
Forfeited/Cancelled (in shares) (266,433) (29,788)        
Outstanding, ending balance (in shares) 4,410,258 2,936,044 2,096,836      
Vested and expected to vest (in shares) 4,410,258          
Vested and exercisable (in shares) 2,519,673          
Weighted Average Exercise Price [Abstract]            
Outstanding, beginning balance (in dollars per share) $ 2.87 $ 2.97        
Granted (in dollars per share) 3.2 2.64        
Exercised (in dollars per share) 1.09 1.09        
Forfeited/Cancelled (in dollars per share) 3.66 6.21        
Outstanding, ending balance (in dollars per share) 2.98 $ 2.87 $ 2.97      
Vested and expected to vest (in dollars per share) 2.98          
Vested and exercisable (in dollars per share) $ 2.77          
Weighted average remaining contractual term, outstanding 7 years 9 months 21 days 7 years 9 months 25 days 8 years 2 months 12 days      
Weighted average remaining contractual term, vested and expected to vest 7 years 9 months 21 days          
Weighted average remaining contractual term, vested and exercisable 6 years 8 months 19 days          
Aggregate intrinsic value, outstanding [1] $ 2,385,000 $ 3,314,000 $ 2,795,000      
Aggregate intrinsic value, vested and expected to vest [1] 2,385,000          
Aggregate intrinsic value, vested and exercisable [1] $ 607,000          
Aggregate intrinsic value (in dollars per share) $ 3.01 $ 3.53        
Weighted average fair value per share of options granted (in dollars per share) $ 2.53 $ 2.06        
[1] The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the fair value of our common stock as of December 31, 2023 and 2022 of $3.01 and $3.53 per share, respectively.