Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	$ 7,294	$ 6,377
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	10,023	9,051
Interest rate swap contracts [Member] | Derivatives Designated as Cash Flow Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives
Interest rate swap contracts [Member] | Derivatives Designated as Cash Flow Hedging Instruments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	1,775	1,802
Commitments to originate fixed rate mortgage loans to be sold [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	3,065	1,864
Commitments to originate fixed rate mortgage loans to be sold [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	2
Commitments to sell fixed rate mortgage loans [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	4
Commitments to sell fixed rate mortgage loans [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	3,889	2,580
Interest rate swaps with customers [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives	4,225	4,513
Interest rate swaps with customers [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives
Mirror swaps with counterparties [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives
Mirror swaps with counterparties [Member] | Derivatives not Designated as Hedging Instruments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives	$ 4,357	$ 4,669