Commitments and Contingencies (Financial Instruments with Off Balance Sheet Risk) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Commitments to originate fixed rate mortgage loans to be sold [Member] | Forward Contracts [Member] | Notional or Principal Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	$ 56,179	$ 67,792
Commitments to sell fixed rate mortgage loans [Member] | Forward Contracts [Member] | Notional or Principal Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risk, Liability	83,452	116,162
Interest rate swaps with customers [Member] | Interest Rate Swap [Member] | Notional or Principal Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	63,891	70,493
Mirror swaps with counterparties [Member] | Interest Rate Swap [Member] | Notional or Principal Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risk, Liability	63,891	70,493
Interest rate swap contracts [Member] | Interest Rate Swap [Member] | Notional or Principal Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risk, Liability	32,991	32,991
Commitments to extend credit on commerical loans [Member] | Commitments to Extend Credit [Member] | Contract Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	223,227	223,426
Commitments to extend credit on home equity lines [Member] | Commitments to Extend Credit [Member] | Contract Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	190,544	184,941
Commitments to extend credit on other loans [Member] | Commitments to Extend Credit [Member] | Contract Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	31,163	30,504
Commitments to extend credit on standby letters of credit [Member] | Commitments to Extend Credit [Member] | Contract Amount [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance Sheet Risks, Asset	$ 1,216	$ 1,039