Annual report pursuant to Section 13 and 15(d)

Equity Compensation - Narrative (Details)

v3.20.4
Equity Compensation - Narrative (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Equity-based compensation expense $ 5,184 $ 3,843 $ 3,098
Stock Option      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Options outstanding (in shares) 912,923 1,116,045  
Share price (in usd per share) $ 13.23 $ 27.95 $ 30.45
Weighted average fair value of options vested (in usd per share) $ 14.77 $ 15.91 $ 16.54
Total fair value of options that vested during the year $ 1,400 $ 1,600 $ 1,400
Total compensation costs related to non-vested awards $ 4,300    
Weighted average period (in years) 2 years    
Weighted average fair value of options granted (in usd per share) $ 0 $ 11.93 $ 14.64
Restricted Stock Units (RSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Period of options granted (in years) 3 years    
Total compensation costs related to non-vested awards $ 2,700    
Weighted average period (in years) 1 year 6 months    
Number of awards granted in period (in shares) 190,100    
Weighted-average price of awards (in usd per share) $ 19.69    
Number of awards vested in period (in shares) 44,800    
Equity-based compensation expense $ 2,600    
Employee Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Share price (in usd per share) $ 6.73    
Cash compensation limit $ 25    
Common stock price to market value (percentage) 85.00%    
Number of shares employees had subscribed to purchase (in shares) 533,138    
Weighted average fair value of options granted (in usd per share) $ 3.43 $ 8.26 $ 8.48
Stock Incentive Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Stock option exercisable period (not exceeding, in years) 10 years    
Period of options granted (in years) 5 years    
Options outstanding (in shares) 485,027    
Directors Stock Option Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Stock option exercisable period (not exceeding, in years) 10 years    
Period of options granted (in years) 6 months    
Options outstanding (in shares) 92,115    
Long Term Incentive Plan      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Period of options granted (in years) 6 months    
Options outstanding (in shares) 557,238    
Options available for future grant (in shares) 1,123,291    
Director      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Period of options granted (in years) 6 months    
Key Employee      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Period of options granted (in years) 5 years    
Key Employee | Restricted Stock Units (RSUs)      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Period of options granted (in years) 3 years    
Maximum      
Share-based Compensation Arrangement by Share-based Payment Award [Roll Forward]      
Stock option exercisable period (not exceeding, in years) 10 years