Shareholders' Equity (Details) (USD $)
12 Months Ended 0 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Jun. 18, 2013
Jun. 10, 2013
Sep. 09, 2013
Dec. 19, 2008
Class of Stock [Line Items]              
Preferred stock issued (in shares) 0 0          
Public offering, value, now closed   $ 65,419,000          
Antidilutive securities excluded from computation of earnings per share (shares) 396,000 460,000 216,905        
Trust Preferred Securities Subject to Mandatory Redemption              
Class of Stock [Line Items]              
Financial instruments subject to mandatory redemption, settlement terms, number of series           2  
Common Stock              
Class of Stock [Line Items]              
Public offering, value, now closed         60,000,000    
Share price (in dollars per share)         $ 12.00    
Public offering, exercise of underwriters option       9,000,000      
United States Department of Treasury              
Class of Stock [Line Items]              
Number of warrants issued (in shares) 2,665,946            
Warrant exercise price (in USD per warrant) 2.71            
Preferred stock issued (in shares)             48,200
Warrants purchase price             $ 48,200,000