Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation Plans (Details)

v3.20.1
Stock-Based Compensation Plans (Details) - USD ($)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Mar. 02, 2019
Apr. 30, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Mar. 01, 2018
May 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares available for issuance (in shares)     310,086        
Tax withholding associated with awards issued     $ 955 $ 641 $ 500    
Compensation expense not yet recognized     $ 873 $ 1,500      
Weighted average amortization period of compensation not yet recognized     1 year 9 months 31 days 1 year 9 months 26 days      
Restricted Stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock-based compensation expense     $ 3,264 $ 2,885 3,058    
Tax withholding associated with awards issued     688 641 500    
Stock-based compensation included in costs and operating expenses     3,264 3,027 3,068    
Income tax benefit recognized for stock-based compensation     (663) (755) (1,180)    
Stock-based compensation expense, net of income tax benefit     2,601 2,272 1,888    
Restricted Stock | Non-employee Directors              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock-based compensation expense     597 553 642    
Restricted Stock | Employee              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Stock-based compensation expense     $ 2,667 $ 2,332 $ 2,416    
Restricted Stock Plan 2006              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Shares authorized (in shares)     1,000,000       500,000
Restricted Stock Plan 2006 | Non-employee Directors              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock awarded (in shares)     18,900 11,200 16,100    
Stock-based compensation expense     $ 597 $ 553 $ 642    
Restricted Stock Plan 2006 | Employee              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock awarded (in shares) 44,839            
Grant date fair value (in dollars per share) $ 34.84            
Vested award is paid in our shares 100.00%         100.00%  
Restricted Stock Plan 2006 | President, CEO, and COO              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Restricted stock awarded (in shares)   20,348          
Grant date fair value (in dollars per share)   $ 30.66          
Stock-based compensation expense   $ 736          
Tax withholding associated with awards issued   $ 267          
Restricted Stock Plan 2006 | Restricted Stock              
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]              
Grant date fair value (in dollars per share)     $ 31.58 $ 49.38 $ 39.85