Loans Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	$ 15,003	$ 14,689	$ 14,014
Charge-offs	(782)	(774)	(894)
Recoveries	232	243	267
Provision	845	845	1,302
Allowance for Credit Losses, Ending Balance	15,298	15,003	14,689
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	853
Allowance for Loan Losses - Collectively Evaluated for Impairment	14,445	15,003
Ending Loan Balance - Individually Evaluated for Impairment	5,253	4,395
Ending Loan Balance - Collectively Evaluated for Impairment	1,167,088	1,127,062
Commercial [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	1,927	2,037	1,304
Charge-offs	(90)	(105)	(30)
Recoveries	23	17	5
Provision	484	(22)	758
Allowance for Credit Losses, Ending Balance	2,344	1,927	2,037
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	853
Allowance for Loan Losses - Collectively Evaluated for Impairment	1,491	1,927
Ending Loan Balance - Individually Evaluated for Impairment	1,432	66
Ending Loan Balance - Collectively Evaluated for Impairment	104,104	99,725
Commercial Construction [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	602	135	0
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	(1)	467	135
Allowance for Credit Losses, Ending Balance	601	602	135
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	601	602
Ending Loan Balance - Individually Evaluated for Impairment	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	29,149	11,083
Commercial Real Estate [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	3,136	2,993	4,000
Charge-offs	(206)	0	0
Recoveries	0	0	0
Provision	120	143	(1,007)
Allowance for Credit Losses, Ending Balance	3,050	3,136	2,993
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	3,050	3,136
Ending Loan Balance - Individually Evaluated for Impairment	2,528	1,953
Ending Loan Balance - Collectively Evaluated for Impairment	242,649	230,196
Other Consumer [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	350	328	0
Charge-offs	(52)	(42)	0
Recoveries	9	28	0
Provision	(3)	36	328
Allowance for Credit Losses, Ending Balance	304	350	328
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	304	350
Ending Loan Balance - Individually Evaluated for Impairment	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	6,684	6,318
Automobile [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	4,496	4,760	4,901
Charge-offs	(401)	(480)	(864)
Recoveries	200	198	262
Provision	241	18	461
Allowance for Credit Losses, Ending Balance	4,536	4,496	4,760
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	4,536	4,496
Ending Loan Balance - Individually Evaluated for Impairment	203	268
Ending Loan Balance - Collectively Evaluated for Impairment	348,897	322,107
Residential [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	3,414	3,163	2,954
Charge-offs	(33)	(147)	0
Recoveries	0	0	0
Provision	24	398	209
Allowance for Credit Losses, Ending Balance	3,405	3,414	3,163
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	3,405	3,414
Ending Loan Balance - Individually Evaluated for Impairment	1,090	2,108
Ending Loan Balance - Collectively Evaluated for Impairment	435,605	457,633
Unallocated [Member]
Rollfoward of the Allowance for Loan Losses for the Quarterly Report [Roll Forward]
Allowance for Credit Losses, Beginning Balance	1,078	1,273	855
Charge-offs	0	0	0
Recoveries	0	0	0
Provision	(20)	(195)	418
Allowance for Credit Losses, Ending Balance	1,058	1,078	1,273
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for Loan Losses - Individually Evaluated for Impairment	0
Allowance for Loan Losses - Collectively Evaluated for Impairment	1,058	1,078
Ending Loan Balance - Individually Evaluated for Impairment	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	$ 0	$ 0

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A valuation allowance for financing receivables that are expected to be uncollectible.

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-Name Accounting Standards Codification

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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-Name Accounting Standards Codification

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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-Name Accounting Standards Codification

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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-Name Accounting Standards Codification

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Amount of direct write-downs of financing receivables charged against the allowance.

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-Name Accounting Standards Codification

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The balance of financing receivables that were collectively evaluated for impairment.

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The sum of the periodic provision charged to earnings, based on an assessment of uncollectibility from the counterparty on account of loan, lease or other credit losses, to reduce these accounts to the amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Paragraph 168, 169, 170

-IssueDate 2006-05-01

-Chapter 5

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Section S99

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