Loans and Allowance for Loan Losses (Details 7) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012 Contract	Sep. 30, 2011 Contract	Sep. 30, 2012 Contract	Sep. 30, 2011 Contract
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	6	16	17	48
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	$ 18,175,000	$ 3,739,000	$ 24,871,000	$ 18,190,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	18,170,000	3,579,000	24,863,000	17,511,000
Total commercial [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	6	16	17	48
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	18,175,000	3,739,000	24,871,000	18,190,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	18,170,000	3,579,000	24,863,000	17,511,000
Total commercial [Member] | Commercial and industrial [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	1	2	6	14
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	133,000	110,000	850,000	2,339,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	128,000	110,000	843,000	2,330,000
Total commercial [Member] | Vacant land, land development and residential construction [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	6	0	8
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	2,219,000	0	3,422,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	0	2,219,000	0	3,421,000
Total commercial [Member] | Real estate - owner occupied [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	0	5	7
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	0	1,588,000	3,973,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	0	0	1,587,000	3,466,000
Total commercial [Member] | Real estate - non-owner occupied [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	5	2	6	9
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	18,042,000	701,000	22,433,000	7,006,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	18,042,000	701,000	22,433,000	7,004,000
Total commercial [Member] | Real estate - multi-family and residential rental [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	6	0	10
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	709,000	0	1,450,000
Financing Receivable Modification, Post-Modification Recorded Principal Balance	0	549,000	0	1,290,000
Total retail [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	0	0	0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	0	0	0
Financing Receivable Modification, Post-Modification Recorded Principal Balance	0	0	0	0
Total retail [Member] | Home equity and other [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	0	0	0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	0	0	0
Financing Receivable Modification, Post-Modification Recorded Principal Balance	0	0	0	0
Total retail [Member] | 1 - 4 family mortgages [Member]
Loans modified as troubled debt restructurings
Financing Receivable Modification, Number of Contracts	0	0	0	0
Financing Receivable Modification, Pre-Modification Recorded Principal Balance	0	0	0	0
Financing Receivable Modification, Post-Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0