Loans Allowance for Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	$ 15,298	$ 15,003
Charge-offs	(890)	(297)
Recoveries	95	67
Provision	100	280
Allowance for Loan Losses, Ending Balance	14,603	15,053
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		853
Allowance for loan losses - Loans Collectively Evaluated for Impairment	14,603	15,053	14,445
Ending Loan Balance - Individually Evaluated for Impairment	2,809	3,864	5,253
Ending Loan Balance - Collectively Evaluated for Impairment	1,161,950	1,133,683	1,167,088
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	2,344	1,927
Charge-offs	(773)	(5)
Recoveries	4	2
Provision	44	(90)
Allowance for Loan Losses, Ending Balance	1,619	1,834
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		853
Allowance for loan losses - Loans Collectively Evaluated for Impairment	1,619	1,834	1,491
Ending Loan Balance - Individually Evaluated for Impairment	37	62	1,432
Ending Loan Balance - Collectively Evaluated for Impairment	89,130	102,091	104,104
Commercial Construction [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	601	602
Charge-offs	0	0
Recoveries	0	0
Provision	11	59
Allowance for Loan Losses, Ending Balance	612	661
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	612	661	601
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	27,380	10,814	29,149
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	3,050	3,136
Charge-offs	(11)	(167)
Recoveries	0	0
Provision	340	328
Allowance for Loan Losses, Ending Balance	3,379	3,297
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	3,379	3,297	3,050
Ending Loan Balance - Individually Evaluated for Impairment	1,505	1,454	2,528
Ending Loan Balance - Collectively Evaluated for Impairment	253,737	232,863	242,649
Other Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	304	350
Charge-offs	(8)	(19)
Recoveries	0	6
Provision	12	15
Allowance for Loan Losses, Ending Balance	308	352
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	308	352	304
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	7,031	6,470	6,684
Automobile [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	4,536	4,496
Charge-offs	(98)	(106)
Recoveries	91	59
Provision	(235)	81
Allowance for Loan Losses, Ending Balance	4,294	4,530
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	4,294	4,530	4,536
Ending Loan Balance - Individually Evaluated for Impairment	182	240	203
Ending Loan Balance - Collectively Evaluated for Impairment	353,819	328,436	348,897
Residential [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	3,405	3,414
Charge-offs	0	0
Recoveries	0	0
Provision	(13)	(114)
Allowance for Loan Losses, Ending Balance	3,392	3,300
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	3,392	3,300	3,405
Ending Loan Balance - Individually Evaluated for Impairment	1,085	2,108	1,090
Ending Loan Balance - Collectively Evaluated for Impairment	430,853	453,009	435,605
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Allowance for Loan Losses, Beginning Balance	1,058	1,078
Charge-offs	0	0
Recoveries	0	0
Provision	(59)	1
Allowance for Loan Losses, Ending Balance	999	1,079
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Allowance for loan losses - Loans Individually Evaluated for Impairment	0		0
Allowance for loan losses - Loans Collectively Evaluated for Impairment	999	1,079	1,058
Ending Loan Balance - Individually Evaluated for Impairment	0	0	0
Ending Loan Balance - Collectively Evaluated for Impairment	$ 0	$ 0	$ 0

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

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

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

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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.

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-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

-Paragraph 1

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