Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Options Other Info (Details)

v3.21.2
Stockholders' Equity - Options Other Info (Details) - USD ($)
$ / shares in Units, $ in Millions
9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Options outstanding    
Intrinsic value of options exercisable $ 0.5  
Closing price of Company's stock (in dollars per share) $ 1.23  
Employee Stock Option    
Options outstanding    
Unrecognized compensation expense $ 5.9  
Weighted average remaining period for recognition of unrecognized compensation expense 3 years 3 days  
Per-share weighted-average grant date fair value of options granted (in dollars per share) $ 1.45 $ 0.73
Employee Stock Option | Weighted-average    
Weighted-average assumptions:    
Expected term of options (in years) 6 years 1 month 6 days 5 years 8 months 12 days
Risk-free interest rate (as a percent) 0.90% 0.70%
Expected volatility (as a percent) 97.80% 96.10%