Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Stock Option Activity (Details)

v3.20.4
Stock-Based Compensation - Stock Option Activity (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Number of Options    
Number of options exercisable (in shares) 1,972,740  
Weighted Average Exercise Price per Option    
Weighted average exercise price per option, exercisable (in usd per share) $ 2.1  
Weighted Average Grant Date Fair Value per Option    
Weighted average remaining contractual term, outstanding 5 years 6 months  
Weighted average remaining contractual term, exercisable 5 years 9 months 18 days  
Stock Option | Directors, officers consultants and employees    
Number of Options    
Number of options outstanding, beginning balance (in shares) 3,725,000 3,867,621
Number of options granted (in shares) 877,575 2,450,000
Number of options exercised (in shares) (2,112,392) (736,552)
Number of options forfeited (in shares) (118,943) (907,500)
Number of options exercised (in shares) (20,000) (948,569)
Number of options outstanding, ending balance (in shares) 2,351,240 3,725,000
Weighted Average Exercise Price per Option    
Weighted average exercise price per option outstanding, beginning balance (in usd per share) $ 2.3 $ 4.1
Weighted average exercise price per option outstanding, grants in period (in usd per share) 1.9 1.0
Weighted average exercise price per option outstanding, exercised in period (in usd per share) 2.4 0.7
Weighted average exercise price per option outstanding, forfeited in period (in usd per share) 5.8 4.5
Weighted average exercise price per option outstanding, expirations in period (in usd per share) 2.4 5.0
Weighted average exercise price per option outstanding, ending balance (in usd per share) 2.0 2.3
Weighted Average Grant Date Fair Value per Option    
Weighted average grant date fair value per option, grants in period (in usd per share) $ 0.6 $ 0.5