Annual report pursuant to Section 13 and 15(d)

Stock Option Plans - Assumptions Used To Compute The Fair Value Of Stock Options (Details)

v3.20.4
Stock Option Plans - Assumptions Used To Compute The Fair Value Of Stock Options (Details) - USD ($)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Assumptions for Black-Scholes:      
Expected annual dividends $ 0 $ 0 $ 0
Value of options granted:      
Number of options granted 1,481,000 73,500 330,500
Weighted average fair value per share $ 1.08 $ 1.71 $ 5.01
Fair value of options issued $ 1,602,267 $ 125,814 $ 1,655,390
Minimum [Member]      
Assumptions for Black-Scholes:      
Expected term in years 6 years 2 months 12 days 6 years 2 months 12 days 6 years 4 months 24 days
Volatility 73.30% 79.40% 108.90%
Risk-free interest rate 0.41% 1.63% 2.95%
Maximum      
Assumptions for Black-Scholes:      
Expected term in years 6 years 7 months 6 days 6 years 3 months 18 days 6 years 7 months 6 days
Volatility 76.80% 89.40% 119.40%
Risk-free interest rate 0.55% 1.68% 3.08%