Loans, Allowance for Loan and Lease Losses, and Reserve for Off-Balance Sheet Credit Commitments (Details 5) (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, 2012	Dec. 31, 2011	Sep. 30, 2012 Total Troubled Debt Restructured Loans contract	Sep. 30, 2012 Total Troubled Debt Restructured Loans contract	Sep. 30, 2012 Commercial contract	Sep. 30, 2012 Commercial contract	Sep. 30, 2012 Commercial real estate mortgages contract	Sep. 30, 2012 Fixed contract	Sep. 30, 2012 Fixed contract	Sep. 30, 2012 Real estate construction contract	Sep. 30, 2012 Construction contract	Sep. 30, 2012 Land contract	Sep. 30, 2012 Land contract	Sep. 30, 2012 Equity lines of credit contract	Sep. 30, 2012 Equity lines of credit contract
Financing Receivable, Impaired
Troubled debt restructured loans on accrual	$ 70,800,000	$ 46,600,000
TDR loans	113,800,000	89,400,000
Specific Reserves	1,300,000	1,700,000
Number of Contracts			11	26	6	15	2	3	4	4	3	1	1	1	1
Pre-Modification Outstanding Principal			11,879,000	78,384,000	1,624,000	36,785,000	15,832,000	1,578,000	2,233,000	23,277,000	14,857,000	8,420,000	8,420,000	257,000	257,000
Period-End Outstanding Principal			10,863,000	63,123,000	1,538,000	23,219,000	16,353,000	1,078,000	1,078,000	22,324,000	14,226,000	8,098,000	8,098,000	149,000	149,000
Financial Effects			$ 11,277,000	$ 11,277,000	$ 10,528,000	$ 10,528,000		$ 485,000	$ 485,000	$ 264,000		$ 264,000	$ 264,000