Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Summary of Stock Option Information by Exercise Price Range (Details)

v3.20.4
Stock-Based Compensation - Summary of Stock Option Information by Exercise Price Range (Details)
12 Months Ended
Dec. 31, 2020
$ / shares
shares
Number of options outstanding | shares 3,624,000
Options outstanding, weighted - average remaining contractual life in years 8 years
Options outstanding, weighted - average exercise price $ 5.85
Number of options exercisable | shares 1,247,000
Options exercisable, weighted - average exercise price $ 5.60
Exercise Price Range One [Member]  
Exercise price, upper limit 2.33
Exercise price, lower limit $ 3.63
Number of options outstanding | shares 16,000
Options outstanding, weighted - average remaining contractual life in years 3 years
Options outstanding, weighted - average exercise price $ 2.33
Number of options exercisable | shares 16,000
Options exercisable, weighted - average exercise price $ 2.33
Exercise Price Range Two [Member]  
Exercise price, upper limit 3.64
Exercise price, lower limit $ 4.93
Number of options outstanding | shares 276,000
Options outstanding, weighted - average remaining contractual life in years 6 years
Options outstanding, weighted - average exercise price $ 4.64
Number of options exercisable | shares 168,000
Options exercisable, weighted - average exercise price $ 4.63
Exercise Price Range Three [Member]  
Exercise price, upper limit 4.94
Exercise price, lower limit $ 6.23
Number of options outstanding | shares 2,767,000
Options outstanding, weighted - average remaining contractual life in years 8 years
Options outstanding, weighted - average exercise price $ 5.89
Number of options exercisable | shares 1,063,000
Options exercisable, weighted - average exercise price $ 5.81
Exercise Price Range Four [Member]  
Exercise price, upper limit 6.24
Exercise price, lower limit $ 7.54
Number of options outstanding | shares 565,000
Options outstanding, weighted - average remaining contractual life in years 9 years
Options outstanding, weighted - average exercise price $ 6.33
Number of options exercisable | shares
Options exercisable, weighted - average exercise price $ 0.00