Stockholders' Equity (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 01, 2018
May 16, 2018
May 15, 2018
Mar. 01, 2018
Jun. 01, 2017
Mar. 01, 2017
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Common Stock, Par or Stated Value Per Share $ 0.01             $ 0.01   $ 0.01   $ 0.01
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value     $ 25                  
Share Based Compensation Arrangement By Share Based Payment Award, Options, Aggregate Grant Date Fair Value $ 29   $ 25                  
Shares Reserved (in shares) 1,844,000             1,844,000   1,844,000    
Shares Available to Issue (in shares) 1,306,000             1,306,000   1,306,000    
Payments of Ordinary Dividends, Common Stock                   $ 2,640 $ 1,668  
Options Outstanding (in shares) 1,751,000             1,751,000   1,751,000    
Performance Awards Outstanding (in shares) 526,000             526,000   526,000    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross 1,200   978                  
Unrecognized share based compensation, expected term (in Duration)                   2 years 4 months 12 days    
Directors compensation expense               $ 118 $ 90 $ 202 $ 180  
Stock repurchase program, authorized amount $ 26,000             $ 26,000   $ 26,000    
Dividends declared per common share (in dollars per Share)   $ 0.075     $ 0.075 $ 0.05 $ 0.05 $ 0.075 $ 0.05 $ 0.150 $ 0.100  
Dividends   $ 1,433     $ 1,207 $ 835 $ 833          
Share-Based Compensation Aggrangement, By Share-Based Payment Award, Equity Instrument Other Than Options, Percent Represented By Relative Shareholder Return Performance               50.00%        
Risk-free interest rate               1.61% 1.44%      
Share-Based Compensation Arrangement By Share-Based Payment Award, Non-Option Equity Instruments, Reserved Percentage 200.00%             200.00%   200.00%    
ESPP                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Dividend yield                   0.01%    
Shares purchased through Employee Stock Purchase Plan (in Shares)               10,503   24,441    
Weighted average purchase price of ESPP shares purchased during the period (in Dollars per share)               $ 20.87   $ 21.55    
Share-based compensation expense               $ 53 $ 48 $ 150 $ 144  
Expected volatility                   20.89%    
Expected holding period (years)               6 months 3 months      
Restricted Stock                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based compensation expense               $ 220 $ 183 $ 465 372  
Stock Granted, Value, Share-based Compensation, Net of Forfeitures               2,000        
Unrecognized share based compensation $ 2,400             $ 2,400   $ 2,400    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period               77,260        
Restricted Stock | Maximum [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               3 years        
Stock Options                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Dividend yield                   1.18%    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage                   20.00%    
Share-based compensation expense               $ 200 300 $ 700 800  
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period               5 years        
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period               10 years        
Stock Granted, Value, Share-based Compensation, Net of Forfeitures               $ 1,400        
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross               212,853        
Grants in period, weighted average exercise price (in dollars per share)               $ 25.43        
Expected volatility                   27.08%    
Risk-free interest rate                   2.65%    
Expected holding period (years)                   5 years    
Performance Shares [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period               113,320        
Officers And Key Employees [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Directors compensation expense               $ 344 $ 202 $ 620 $ 257  
Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Granted In Period, Fair Value               $ 2,900        
Share-based Compensation Award, Tranche One [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Annual Vesting Percentage       50.00%                
Share-based Compensation Award, Tranche Two [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Annual Vesting Percentage       25.00%                
Amended And Restated 2006 Plan [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Shares Reserved (in shares) 0             0   0    
Shares Available to Issue (in shares) 0             0   0    
Options Outstanding (in shares) 1,528,000             1,528,000   1,528,000    
Performance Awards Outstanding (in shares) 297,000             297,000   297,000    
Cancelled shares (in shares)                   289,000    
2017 Plan [Member]                        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Shares Reserved (in shares) 1,844,000             1,844,000   1,844,000    
Shares Available to Issue (in shares) 1,306,000             1,306,000   1,306,000    
Options Outstanding (in shares) 223,000             223,000   223,000    
Performance Awards Outstanding (in shares) 229,000             229,000   229,000