Investment Securities (Details 3) (Investment Securities Pledged as Collateral, USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Investment Securities Pledged as Collateral
   
Financial Instruments Owned and Pledged as Collateral [Line Items]    
Public deposits $ 95,003 $ 103,475
Securities sold under repurchase agreements 18,778 21,232
Total pledged securities $ 113,781 $ 124,707