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Stock-Based Compensation - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares available for issuance under plans (in shares) 1,587,625    
Weighted average fair value of stock options granted (in dollars per share)     $ 20.30
Options granted (in shares) 0 0 35,800
Weighted average forfeiture rate 7.40%    
Net proceeds from exercise of stock options $ 1,169 $ 1,266 $ 1,444
Dividend yield     3.60%
Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years    
Expiration period 10 years    
Compensation cost $ 570 649 $ 729
Net proceeds from exercise of stock options 1,169 1,266 1,444
Unrecognized compensation cost $ 344    
Term over which unrecognized compensation cost recognized 8 months 21 days    
Restricted Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 4 years    
Weighted average forfeiture rate 10.20%    
Compensation cost $ 10,606 8,072 $ 7,316
Unrecognized compensation cost $ 10,870    
Term over which unrecognized compensation cost recognized 2 years    
Performance-Based Stock Units      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Vesting period 3 years    
Compensation cost $ 1,873 840  
Unrecognized compensation cost $ 2,739 $ 1,681  
Term over which unrecognized compensation cost recognized 2 years 2 years  
Performance component weight percentage 50.00%    
Minimum shares issued for each PSU (in shares) 0    
Maximum shares issued for each PSU (in shares) 2    
Dividend yield 0.00% 0.00%