Allowance for Loan Loss (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	$ 6,503	$ 7,746	$ 6,919	$ 7,676
Financing Receivable, Allowance for Credit Losses, Charge-offs	(2,137)	(2,029)	(3,824)	(3,325)
Financing Receivable, Allowance for Credit Losses, Recoveries	129	23	200	189
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(2,008)	(2,006)	(3,624)	(3,136)
Provision for loan losses	1,550	600	2,750	1,800
Financing Receivable, Allowance for Credit Losses	6,045	6,340	6,045	6,340
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	731	767	948	972
Financing Receivable, Allowance for Credit Losses, Charge-offs	(152)	(298)	(246)	(659)
Financing Receivable, Allowance for Credit Losses, Recoveries	20	5	28	28
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(132)	(293)	(218)	(631)
Provision for loan losses	155	288	24	421
Financing Receivable, Allowance for Credit Losses	754	762	754	762
Construction And Land Development Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	1,623	2,759	1,470	2,223
Financing Receivable, Allowance for Credit Losses, Charge-offs	0	(1,572)	(231)	(1,717)
Financing Receivable, Allowance for Credit Losses, Recoveries	0	1	1	2
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	0	(1,571)	(230)	(1,715)
Provision for loan losses	(14)	(50)	369	630
Financing Receivable, Allowance for Credit Losses	1,609	1,138	1,609	1,138
Commercial Real Estate Loans, Total [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	2,817	2,722	3,009	2,893
Financing Receivable, Allowance for Credit Losses, Charge-offs	(1,626)	(79)	(2,844)	(419)
Financing Receivable, Allowance for Credit Losses, Recoveries	71	0	71	0
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(1,555)	(79)	(2,773)	(419)
Provision for loan losses	1,396	0	2,422	169
Financing Receivable, Allowance for Credit Losses	2,658	2,643	2,658	2,643
Residential Real Estate Loans, Total [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	1,278	1,104	1,363	1,336
Financing Receivable, Allowance for Credit Losses, Charge-offs	(324)	(73)	(435)	(519)
Financing Receivable, Allowance for Credit Losses, Recoveries	35	14	85	149
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(289)	(59)	(350)	(370)
Provision for loan losses	(42)	359	(66)	438
Financing Receivable, Allowance for Credit Losses	947	1,404	947	1,404
Consumer Installment and Revolving Loans [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	54	190	129	141
Financing Receivable, Allowance for Credit Losses, Charge-offs	(35)	(7)	(68)	(11)
Financing Receivable, Allowance for Credit Losses, Recoveries	3	3	15	10
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	(32)	(4)	(53)	(1)
Provision for loan losses	55	(8)	1	38
Financing Receivable, Allowance for Credit Losses	77	178	77	178
Financing Receivable, Allowance For Loan Loss, Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Financing Receivable, Allowance for Credit Losses	0	204	0	111
Financing Receivable, Allowance for Credit Losses, Charge-offs	0	0	0	0
Financing Receivable, Allowance for Credit Losses, Recoveries	0	0	0	0
Financing Receivable Allowance For Credit Losses Net Chargeoffs Recoveries	0	0	0	0
Provision for loan losses	0	11	0	104
Financing Receivable, Allowance for Credit Losses	$ 0	$ 215	$ 0	$ 215

No authoritative reference available.

No definition available.

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953423-111524

-Subparagraph (c)(1)

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- Definition

Reduction to the allowance for credit losses related to collections on financing receivables which have been partially or fully charged off as bad debts.

+ References

+ Details

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- Definition

Reduction to the allowance for credit losses related to financing receivables deemed uncollectible.

+ References

+ Details

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- Definition

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 FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-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 SEC

-Name Regulation S-X (SX)

-Number 210

-Article 9

-Section 04

-Paragraph 11

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 5

-Paragraph 168, 169, 170

-IssueDate 2006-05-01

-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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