Troubled Debt Restructuring (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	$ 1,051		$ 1,068
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	3,468		4,107
Impaired Financing Receivable, Trouble Debt Structuring, Total	4,519		5,175
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	331		263
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	2
Financing Receivable, Modification, Pre-Modification Recorded Investment	562
Financing Receivable, Modifications, Post-Modifications Recorded Investment	562
Financing Receivable, Modifications, Subsequent Default [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	1	1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	1,197	2,386
Commercial and Industrial Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	160		169
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	0		0
Impaired Financing Receivable, Trouble Debt Structuring, Total	160		169
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	0		0
Construction And Land Development Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	1,615		1,623
Impaired Financing Receivable, Trouble Debt Structuring, Total	1,615		1,623
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	121		129
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts		2
Financing Receivable, Modification, Pre-Modification Recorded Investment		2,842
Financing Receivable, Modifications, Post-Modifications Recorded Investment		1,753
Financing Receivable, Modifications, Subsequent Default [Line Items]
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	1	1
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	1,197	2,386
Commercial Real Estate Owner Occupied Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	891		899
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	307		1,045
Impaired Financing Receivable, Trouble Debt Structuring, Total	1,198		1,944
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	126		134
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts		1
Financing Receivable, Modification, Pre-Modification Recorded Investment		818
Financing Receivable, Modifications, Post-Modifications Recorded Investment		818
Commercial Real Estate Other Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	429		432
Impaired Financing Receivable, Trouble Debt Structuring, Total	429		432
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	0		0
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	1	2
Financing Receivable, Modification, Pre-Modification Recorded Investment	431	1,804
Financing Receivable, Modifications, Post-Modifications Recorded Investment	431	1,657
Commercial Real Estate Loans, Total [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	891		899
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	736		1,477
Impaired Financing Receivable, Trouble Debt Structuring, Total	1,627		2,376
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	126		134
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	1	3
Financing Receivable, Modification, Pre-Modification Recorded Investment	431	2,622
Financing Receivable, Modifications, Post-Modifications Recorded Investment	431	2,475
Residential Real Estate Consumer Mortgage Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	802		819
Impaired Financing Receivable, Trouble Debt Structuring, Total	802		819
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	84		0
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	1
Financing Receivable, Modification, Pre-Modification Recorded Investment	131
Financing Receivable, Modifications, Post-Modifications Recorded Investment	131
Residential Real Estate Investment Property Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	315		188
Impaired Financing Receivable, Trouble Debt Structuring, Total	315		188
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	0		0
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	0
Financing Receivable, Modification, Pre-Modification Recorded Investment	0
Financing Receivable, Modifications, Post-Modifications Recorded Investment	0
Residential Real Estate Loans, Total [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	1,117		1,007
Impaired Financing Receivable, Trouble Debt Structuring, Total	1,117		1,007
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	84		0
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts	1
Financing Receivable, Modification, Pre-Modification Recorded Investment	131
Financing Receivable, Modifications, Post-Modifications Recorded Investment	131
Consumer Installment and Revolving Loans [Member]
Impaired Financing Receivable And Troubled Debt Restructing [Line Items]
Impaired Financing Receivable, Troubled Debt Restructuring, Still Accruing	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Nonaccrual	0		0
Impaired Financing Receivable, Trouble Debt Structuring, Total	0		0
Impaired Financing Receivable, Troubled Debt Restructuring, Allowance for Credit Losses	0		0
Trouble Debt Restructurings Total [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modification, Number of Contracts		5
Financing Receivable, Modification, Pre-Modification Recorded Investment		5,464
Financing Receivable, Modifications, Post-Modifications Recorded Investment		$ 4,228