Parent corporation only financial statements (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Assets        
Cash and due from banks $ 10,848 $ 17,076    
Total assets 444,802 419,941 $ 434,004  
Liabilities        
Other liabilities 6,596 8,116    
Total liabilities 401,188 389,582    
Shareholders' equity        
Preferred stock 23 23    
Common stock 5,629 5,562    
Additional paid-in capital 58,643 58,497    
Accumulated deficit (21,172) (33,948)    
Accumulated other comprehensive loss (241) (507)    
Total shareholders' equity 43,614 30,359 $ 19,058 $ 18,244
Liabilities and Equity 444,802 419,941    
Parent Company [Member]        
Assets        
Cash and due from banks 1,770 3,494    
Investment in subsidiaries 50,230 38,665    
Investment in special purpose subsidiary 264 264    
Prepaid expenses and other assets 2,935 45    
Total assets 55,199 42,468    
Liabilities        
Balance due to nonbank subsidiaries 8,764 8,764    
Other liabilities 2,821 3,345    
Total liabilities 11,585 12,109    
Shareholders' equity        
Preferred stock 23 23    
Common stock 5,629 5,562    
Additional paid-in capital 58,643 58,497    
Warrant surplus 732 732    
Accumulated deficit (21,172) (33,948)    
Stock in directors rabbi trust (1,034) (1,034)    
Directors deferred fees obligation 1,034 1,034    
Accumulated other comprehensive loss (241) (507)    
Total shareholders' equity 43,614 30,359    
Liabilities and Equity $ 55,199 $ 42,468