Derivative Financial Instruments (Assets and liabilities) (Details) (USD $)
In Thousands, unless otherwise specified
Mar. 31, 2014
Dec. 31, 2013
Derivative Financial Instruments Not Designated as Hedging Instruments    
Asset Derivatives $ 20,370 $ 21,769
Liability Derivatives 20,168 21,951
Interest Rate Lock Commitments
   
Derivative Financial Instruments Not Designated as Hedging Instruments    
Asset Derivatives 443 574
Liability Derivatives 0 38
Forward Commitments
   
Derivative Financial Instruments Not Designated as Hedging Instruments    
Asset Derivatives 11 215
Liability Derivatives 8 4
Interest Rate Swap Agreements
   
Derivative Financial Instruments Not Designated as Hedging Instruments    
Asset Derivatives 19,849 20,852
Liability Derivatives 20,003 21,009
Foreign Exchange Contracts
   
Derivative Financial Instruments Not Designated as Hedging Instruments    
Asset Derivatives 67 128
Liability Derivatives $ 157 $ 900