Loans, Allowance for Loan and Lease Losses, and Reserve for Off-Balance Sheet Credit Commitments (Details 6) (USD $)			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended				3 Months Ended	9 Months Ended		3 Months Ended	9 Months Ended			3 Months Ended	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Total Troubled Debt Restructured Loans item	Sep. 30, 2012 Total Troubled Debt Restructured Loans item	Sep. 30, 2013 Total Troubled Debt Restructured Loans item	Sep. 30, 2012 Total Troubled Debt Restructured Loans item	Sep. 30, 2013 Commercial item	Sep. 30, 2012 Commercial item	Sep. 30, 2013 Commercial item	Sep. 30, 2012 Commercial item	Sep. 30, 2013 Commercial real estate mortgages item	Sep. 30, 2012 Commercial real estate mortgages item	Sep. 30, 2012 Home equity loans and lines of credit item	Sep. 30, 2013 Home equity loans and lines of credit item	Sep. 30, 2012 Home equity loans and lines of credit item	Sep. 30, 2012 Fixed item	Sep. 30, 2012 Fixed item	Sep. 30, 2012 Real estate construction item	Sep. 30, 2012 Construction item	Sep. 30, 2012 Land item	Sep. 30, 2012 Land item
Financing Receivable, Impaired
Impaired restructured loans on accrual status	$ 52,500,000	$ 48,800,000
TDR loans	69,300,000	94,900,000
Specific Reserves	900,000	1,700,000
Number of Contracts			2	11	14	26	2	6	12	15	1	2	1	1	1	3	4	4	3	1	1
Pre-Modification Outstanding Principal			7,575,000	11,879,000	17,150,000	78,384,000	7,575,000	1,624,000	16,258,000	36,785,000	547,000	15,832,000	257,000	345,000	257,000	1,578,000	2,233,000	23,277,000	14,857,000	8,420,000	8,420,000
Period-End Outstanding Principal			7,486,000	10,863,000	14,157,000	63,123,000	7,486,000	1,538,000	13,624,000	23,219,000	533,000	16,353,000	149,000		149,000	1,078,000	1,078,000	22,324,000	14,226,000	8,098,000	8,098,000
Financial Effects			$ 344,000	$ 11,277,000	$ 344,000	$ 11,277,000	$ 344,000	$ 10,528,000	$ 344,000	$ 10,528,000						$ 485,000	$ 485,000	$ 264,000		$ 264,000	$ 264,000