Loans and Leases and the Allowance for Loan and Lease Losses (Details 6) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2012 contract	Sep. 30, 2012 contract M	Dec. 31, 2011
Loans and Leases and the Allowance for Loan and Lease Losses
Loans modified in a TDR	$ 41,300,000	$ 41,300,000	$ 38,800,000
Lease financing modifications, forbearance period (in months)		3
Loans Modified as a TDR
Number of Contracts	66	158
Recorded Investment (as of period end)	3,392,000	9,575,000
Increase in Allowance (as of period end)	516,000	965,000
TDRs that Defaulted During the Period, Within Twelve Months of their Modification Date
Number of Contracts	3	8
Recorded Investment (as of period end)	6,000	734,000
Minimum
TDRs that Defaulted During the Period, Within Twelve Months of their Modification Date
Default period past due following modification of loans in TDR (in days)		60
Commercial
Loans Modified as a TDR
Number of Contracts		1
Recorded Investment (as of period end)		953,000
Construction
Loans Modified as a TDR
Number of Contracts		1
Recorded Investment (as of period end)		953,000
Consumer
Loans Modified as a TDR
Number of Contracts	66	157
Recorded Investment (as of period end)	3,392,000	8,622,000
Increase in Allowance (as of period end)	516,000	965,000
TDRs that Defaulted During the Period, Within Twelve Months of their Modification Date
Number of Contracts	3	8
Recorded Investment (as of period end)	6,000	734,000
Residential Mortgage
Loans and Leases and the Allowance for Loan and Lease Losses
Period of loans modified in TDR (in years)		2
Loans Modified as a TDR
Number of Contracts	6	11
Recorded Investment (as of period end)	2,757,000	7,106,000
Increase in Allowance (as of period end)	513,000	957,000
TDRs that Defaulted During the Period, Within Twelve Months of their Modification Date
Number of Contracts		2
Recorded Investment (as of period end)		702,000
Number of contracts temporarily lowered		1
Land Loans | Minimum
Loans and Leases and the Allowance for Loan and Lease Losses
Period for the balloon payment extension (in years)		1
Land Loans | Maximum
Loans and Leases and the Allowance for Loan and Lease Losses
Period for the balloon payment extension (in years)		3
Automobile
Loans Modified as a TDR
Number of Contracts	60	146
Recorded Investment (as of period end)	635,000	1,516,000
Increase in Allowance (as of period end)	3,000	8,000
TDRs that Defaulted During the Period, Within Twelve Months of their Modification Date
Number of Contracts	3	6
Recorded Investment (as of period end)	$ 6,000	$ 32,000