Annual report pursuant to Section 13 and 15(d)

Stock - Based Compensation - Stock Options by Exercise Price Range (Details)

v3.20.4
Stock - Based Compensation - Stock Options by Exercise Price Range (Details)
 12 Months Ended
Dec. 31, 2020
$ / shares
shares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Number of outstanding stock options (in shares) | shares 179,531
Number of exercisable stock options (in shares) | shares 86,531
Exercise Price of $11.35  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 11.35
Number of outstanding stock options (in shares) | shares 11,713
Weighted average exercise price (in dollars per share) $ 11.35
Weighted average remaining contractual life in years 1 year 1 month 6 days
Number of exercisable stock options (in shares) | shares 11,713
Exercisable stock options, weighted average exercise price (in dollars per share) $ 11.35
Exercise Price of $13.70  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 13.70
Number of outstanding stock options (in shares) | shares 13,994
Weighted average exercise price (in dollars per share) $ 13.70
Weighted average remaining contractual life in years 2 years 1 month 6 days
Number of exercisable stock options (in shares) | shares 13,994
Exercisable stock options, weighted average exercise price (in dollars per share) $ 13.70
Exercise Price of $14.76  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 14.76
Number of outstanding stock options (in shares) | shares 8,109
Weighted average exercise price (in dollars per share) $ 14.76
Weighted average remaining contractual life in years 3 years 1 month 17 days
Number of exercisable stock options (in shares) | shares 8,109
Exercisable stock options, weighted average exercise price (in dollars per share) $ 14.76
Exercise Price of $16.01  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 16.01
Number of outstanding stock options (in shares) | shares 20,715
Weighted average exercise price (in dollars per share) $ 16.01
Weighted average remaining contractual life in years 4 years 1 month 9 days
Number of exercisable stock options (in shares) | shares 20,715
Exercisable stock options, weighted average exercise price (in dollars per share) $ 16.01
Exercise Price of $13.00  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 13.00
Number of outstanding stock options (in shares) | shares 105,000
Weighted average exercise price (in dollars per share) $ 13.00
Weighted average remaining contractual life in years 9 years 1 month 6 days
Number of exercisable stock options (in shares) | shares 32,000
Exercisable stock options, weighted average exercise price (in dollars per share) $ 13.00
Exercise price of $7.33  
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]  
Range of exercise prices (in dollars per share) $ 7.33
Number of outstanding stock options (in shares) | shares 20,000
Weighted average exercise price (in dollars per share) $ 7.33
Weighted average remaining contractual life in years 9 years 6 months
Number of exercisable stock options (in shares) | shares 0
Exercisable stock options, weighted average exercise price (in dollars per share) $ 7.33