Stock Based Compensation - Narrative (Details)
9 Months Ended 12 Months Ended
Sep. 30, 2016
USD ($)
director
shares
Sep. 30, 2015
USD ($)
shares
Dec. 31, 2015
USD ($)
shares
Apr. 22, 2008
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum number of common stock authorizes for issuance (in shares) | shares       500,000
Unrecognized compensation expense $ 0      
Regular monthly board retainer director could receive in cash 1,667      
Regular monthly board retainer if restricted stock vested 2,083      
Monthly meeting fees a director could receive in cash 725      
Monthly meeting fees a director could receive if restricted stock vested $ 900      
Number of directors elected to receive stock in lieu of cash | director 13      
Director [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Shares issued as payment for deferred compensation (in shares) | shares     4,158  
Market value of shares issued as payment of deferred compensation     $ 95,000  
Restricted Stock [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum vesting period of granted restricted stock 36 months      
Unrecognized compensation expense $ 585,000   $ 340,000  
Weighted average period for recognition of unrecognized compensation cost 1 year 6 months 4 days      
Share based compensation expense $ 342,000 $ 249,000    
Number of shares issued (in shares) | shares 10,588 8,630    
Recognized share based compensation expense $ 281,000 $ 195,000