Loans and Allowance for Loan Losses Schedule of Impaired Loans With and Without and Allowance (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	$ 6,863	$ 5,378
Impaired loans, with no related allowance, unpaid principal balance	9,309	6,572
Impaired loans, with related allowance, recorded investment	10,088	23,695
Impaired loans, with related allowance, unpaid principal balance	10,088	23,695
Impaired loans, with related allowance- related allowance	4,906	3,182
Impaired loans, recorded investment	16,951	29,073
Impaired loans, unpaid principal balance	19,397	30,267
Impaired loans, related allowance	4,906	3,182
Impaired loans, with no related allowance, average recorded investment	7,596	7,092
Impaired loans, with no related allowance, interest income, accrual method	149	77
Impaired loans, with related allowance, average recorded investment	15,369	19,330
Impaired loans, with related allowance, interest income, accrual method	740	969
Impaired loans, average recorded investment	22,965	26,422	38,552
Impaired loans, interest income, accrual method	889	1,046	1,467
Loans , impaired, interest lost on nonaccrual loans	513	450	664
Commercial Loan [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	282	800
Impaired loans, with no related allowance, unpaid principal balance	292	800
Impaired loans, with related allowance, recorded investment	3,615	4,577
Impaired loans, with related allowance, unpaid principal balance	3,615	4,577
Impaired loans, with related allowance- related allowance	1,297	100
Impaired loans, recorded investment	3,897	5,377
Impaired loans, unpaid principal balance	3,907	5,377
Impaired loans, related allowance	1,297	100
Impaired loans, with no related allowance, average recorded investment	463	1,752
Impaired loans, with no related allowance, interest income, accrual method	80	0
Impaired loans, with related allowance, average recorded investment	1,075	5,419
Impaired loans, with related allowance, interest income, accrual method	38	264
Impaired loans, average recorded investment	1,538	7,171
Impaired loans, interest income, accrual method	118	264
Construction Land and Land Development [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	3,825	0
Impaired loans, with no related allowance, unpaid principal balance	5,292	0
Impaired loans, with related allowance, recorded investment	4,441	17,359
Impaired loans, with related allowance, unpaid principal balance	4,441	17,359
Impaired loans, with related allowance- related allowance	3,000	2,630
Impaired loans, recorded investment	8,266	17,359
Impaired loans, unpaid principal balance	9,733	17,359
Impaired loans, related allowance	3,000	2,630
Impaired loans, with no related allowance, average recorded investment	2,712	126
Impaired loans, with no related allowance, interest income, accrual method	9	6
Impaired loans, with related allowance, average recorded investment	12,440	13,568
Impaired loans, with related allowance, interest income, accrual method	583	671
Impaired loans, average recorded investment	15,152	13,694
Impaired loans, interest income, accrual method	592	677
Residential Mortgage [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	679	1,094
Impaired loans, with no related allowance, unpaid principal balance	679	1,094
Impaired loans, with related allowance, recorded investment	0	283
Impaired loans, with related allowance, unpaid principal balance	0	283
Impaired loans, with related allowance- related allowance	0	84
Impaired loans, recorded investment	679	1,377
Impaired loans, unpaid principal balance	679	1,377
Impaired loans, related allowance	0	84
Impaired loans, with no related allowance, average recorded investment	1,024	1,021
Impaired loans, with no related allowance, interest income, accrual method	5	2
Impaired loans, with related allowance, average recorded investment	314	190
Impaired loans, with related allowance, interest income, accrual method	15	21
Impaired loans, average recorded investment	1,338	1,211
Impaired loans, interest income, accrual method	20	23
Home equity line of credit [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	0	0
Impaired loans, with no related allowance, unpaid principal balance	0	0
Impaired loans, with related allowance, recorded investment	458	156
Impaired loans, with related allowance, unpaid principal balance	458	156
Impaired loans, with related allowance- related allowance	86	156
Impaired loans, recorded investment	458	156
Impaired loans, unpaid principal balance	458	156
Impaired loans, related allowance	86	156
Impaired loans, with no related allowance, average recorded investment	24	62
Impaired loans, with no related allowance, interest income, accrual method	0	3
Impaired loans, with related allowance, average recorded investment	239	12
Impaired loans, with related allowance, interest income, accrual method	15	2
Impaired loans, average recorded investment	263	74
Impaired loans, interest income, accrual method	15	5
Commercial Real Estate [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	2,077	3,484
Impaired loans, with no related allowance, unpaid principal balance	3,046	4,678
Impaired loans, with related allowance, recorded investment	1,574	1,278
Impaired loans, with related allowance, unpaid principal balance	1,574	1,278
Impaired loans, with related allowance- related allowance	523	200
Impaired loans, recorded investment	3,651	4,762
Impaired loans, unpaid principal balance	4,620	5,956
Impaired loans, related allowance	523	200
Impaired loans, with no related allowance, average recorded investment	3,373	4,120
Impaired loans, with no related allowance, interest income, accrual method	55	65
Impaired loans, with related allowance, average recorded investment	1,290	98
Impaired loans, with related allowance, interest income, accrual method	88	8
Impaired loans, average recorded investment	4,663	4,218
Impaired loans, interest income, accrual method	143	73
Consumer and Other Loans [Member]
Loans, Impaired [Line Items]
Impaired loans, with no related allowance, recorded investment	0	0
Impaired loans, with no related allowance, unpaid principal balance	0	0
Impaired loans, with related allowance, recorded investment	0	42
Impaired loans, with related allowance, unpaid principal balance	0	42
Impaired loans, with related allowance- related allowance	0	12
Impaired loans, recorded investment	0	42
Impaired loans, unpaid principal balance	0	42
Impaired loans, related allowance	0	12
Impaired loans, with no related allowance, average recorded investment	0	11
Impaired loans, with no related allowance, interest income, accrual method	0	1
Impaired loans, with related allowance, average recorded investment	11	43
Impaired loans, with related allowance, interest income, accrual method	1	3
Impaired loans, average recorded investment	11	54
Impaired loans, interest income, accrual method	$ 1	$ 4

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=7512638&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 114

-Paragraph 20

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

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Section 563c.102

-Paragraph 8

-Subparagraph j(ii)

-Chapter V

-Subsection I

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 15

-Paragraph 40

-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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Impaired Financing Receivable, with Related Allowance- Related Allowance

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