Loans, Allowance for Loan Losses, and Credit Quality (Details Textuals) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Loans Allowance for Loan Losses and Credit Quality Disclosure (Textuals) [Abstract]
Interest income recognized on accruing restructured loans	$ 1,000,000	$ 6,000,000
Restructured Loans Subsequently Accruing	8,000,000
Performing Restructured Loans	120,093,000	121,087,000
Nonaccrual Restructured Loans	67,811,000	80,590,000
YTD restructured loans still on nonaccrual	$ 4,000,000