Loans, Allowance for Loan Losses and Credit Quality (Details Textual) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Tdrs Recorded Investment On Nonaccrual Status	$ 5,962,000	$ 9,230,000
Loans Allowance for Loan Losses and Credit Quality (Textual) [Abstract]
The amount of deferred fees	3,200,000	2,900,000
Proportion of home equity loans in first lien	61.10%	54.80%
Significant advanced considered for risk rating change	$ 50,000,000
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Days to be termed as non accrual loans	90 days