Loans and the Allowance for Credit Losses (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
Loans and the Allowance for Credit Losses (Textual) [Abstract]
Deferred loan fees and costs	$ 2.6	$ 2.6	$ 3.1
Total residential real estate home equity and consumer loans classified as substandard	13.8	13.8	18.2
Value of restructured contracts greater than $1 million	18.7	18.7
Percentage of TDRs defaulted during the period that were restructured within the last twelve months	5.70%	5.70%
Number of restructured contracts greater than $1 million		10
Percentage of largest restructurings to total restructurings at period end	47.70%	47.70%
Restructure value per contract, minimum	1	1
Tdrs Defaulted Period	90 days
Maximum [Member]
Accounts Notes Loans and Financing Receivable [Line Items]
Concessions granted for majority of ten largest TDRs		1 year
Concessions granted for majority of ten largest TDRs by lengthening the amortization period		5 years
Specific Reserves [Member]
Accounts Notes Loans and Financing Receivable [Line Items]
Specific reserve on largest TDRs	2.9	2.9
Accruing Loans [Member]
Accounts Notes Loans and Financing Receivable [Line Items]
Internally assigned loan grades to residential real estate, home equity and consumer loans	$ 2.9	$ 2.9	$ 4.2