Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Warrant activities (Details)

v3.20.2
Stockholders' Equity - Warrant activities (Details) - Warrants [Member] - USD ($)
 9 Months Ended 12 Months Ended
Sep. 30, 2020
Dec. 31, 2019
Subsidiary or Equity Method Investee [Line Items]    
Number of shares, Outstanding 2,741,180  
Number of shares, Granted 1,849,450  
Number of shares, Forfeited (9)  
Number of shares, Outstanding 4,590,621 2,741,180
Number of shares, Exercisable 4,430,621  
Weighted average exercise price, Outstanding $ 3.19  
Weighted average exercise price, Granted 3.14  
Weighted average exercise price, Forfeited 3.00  
Weighted average exercise price, Outstanding 3.17 $ 3.19
Weighted average exercise price, Exercisable $ 3.21  
Total intrinsic value, Outstanding $ 4,111,018 $ 111,000
Total intrinsic value, Granted 1,657,538  
Total intrinsic value, Forfeited 0  
Total intrinsic value, Exercisable $ 3,816,818  
Weighted average remaining contractual life (years), Outstanding 5 years 1 month 6 days 2 years 8 months 23 days
Weighted average remaining contractual life, Exercisable (years) 5 years 18 days