Annual report pursuant to Section 13 and 15(d)

Stock Based Compensation - Stock Options With Service-based Vesting Conditions (Details)

v3.20.4
Stock Based Compensation - Stock Options With Service-based Vesting Conditions (Details) - Service Based Options - $ / shares
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Number of shares    
Balance, beginning of period (in shares) 4,180,606  
Granted (in shares) 5,938,365  
Exercised (in shares) (75,239)  
Forfeited (in shares) (629,300)  
Expired (in shares) (583,758)  
Balance, end of period (in shares) 8,830,674 4,180,606
Exercisable (in shares) 2,906,450  
Weighted average exercise price per share    
Balance, beginning of period (in dollars per share) $ 4.80  
Granted (in dollars per share) 3.38  
Exercised (in dollars per share) 1.52  
Forfeited (in dollars per share) 3.26  
Expired (in dollars per share) 5.42  
Balance, end of period (in dollars per share) 3.95 $ 4.80
Exercisable (in dollars per share) 4.42  
Weighted average grant date fair value per share    
Balance, beginning of period (in dollars per share) 2.67  
Granted (in dollars per share) 2.16  
Exercised (in dollars per share) 1.34  
Forfeited (in dollars per share) 1.95  
Expired (in dollars per share) 3.02  
Balance, end of period (in dollars per share) 2.36 $ 2.67
Exercisable (in dollars per share) $ 2.46  
Weighted average remaining contractual term (in years)    
Weighted average remaining contractual term 7 years 8 months 12 days 7 years 10 months 24 days
Exercisable 5 years