Impaired Loans and Valuation Allowance for Loan Losses (Details Textual) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Impaired Loans and Valuation Allowance for Loan Losses (Textual) [Abstract]
Newly identified TDRs	$ 1,600,000
Impaired Loans and Valuation Allowance for Loan Losses (Additional Textual) [Abstract]
Loan default period	60 days
Accruing TDRs	41,200,000		41,900,000
Interest income on impaired loans	480,000	669,000
Expected future cash flows of impaired loans	240,000	219,000
Commercial real estate [Member]
Impaired Loans and Valuation Allowance for Loan Losses (Textual) [Abstract]
Newly identified TDRs	1,000,000
Residential real estate [Member]
Impaired Loans and Valuation Allowance for Loan Losses (Textual) [Abstract]
Newly identified TDRs	100,000
Consumer [Member]
Impaired Loans and Valuation Allowance for Loan Losses (Textual) [Abstract]
Newly identified TDRs	$ 100,000