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Allowance for Loan Losses, Nonperforming Assets and Impaired Loans, Troubled Debt Restructurings (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts | 10 |  | 16 | [1]
Pre-Modification Outstanding Principal Balance | $ 1,826 |  | $ 4,120 | [1]
Post-Modification Outstanding Principal Balance | 1,736 | [2] | 3,052 | [1],[2]
Impairment Accrued | 210 |  | 765 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts | 5 |  | 12 | [1]
Principal balance | 1,426 |  | 2,852 | [1]
Impairment Accrued | 167 |  | 698 | [1]
Number of unsecured and fully accrued loans in allowance for loan losses |  |  | 1 |
Number of days delay beyond which restructured loans are secured by real estate, minimum (in days) | 90 days |  |  |
Commercial and Industrial [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 1 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 50 | [1]
Post-Modification Outstanding Principal Balance |  |  | 50 | [1],[2]
Impairment Accrued |  |  | 50 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 1 | [1]
Principal balance |  |  | 50 | [1]
Impairment Accrued |  |  | 50 | [1]
Consumer Real Estate [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Amounts of partial charge offs included in troubled debt restructurings | 109 |  | 1,143 |
Number of loans that received partial charge-offs | 2 |  |  |
Number of loans modified and reported as trouble debt restructurings |  |  | 5 |
Number of loans with payment relief | 4 |  |  |
Consumer Real Estate [Member] | Closed-end First Liens [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts | 5 |  |  |
Pre-Modification Outstanding Principal Balance | 389 |  |  |
Post-Modification Outstanding Principal Balance | 348 | [2] |  |
Impairment Accrued | 43 |  |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts | 1 |  |  |
Principal balance | 96 |  |  |
Impairment Accrued | 0 |  |  |
Consumer Real Estate [Member] | Closed-end Junior Liens [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts | 1 |  |  |
Pre-Modification Outstanding Principal Balance | 147 |  |  |
Post-Modification Outstanding Principal Balance | 93 | [2] |  |
Impairment Accrued | 0 |  |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts | 1 |  |  |
Principal balance | 81 |  |  |
Impairment Accrued | 0 |  |  |
Consumer Real Estate [Member] | Closed end Consumer Real Estate [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 290 | [1]
Post-Modification Outstanding Principal Balance |  |  | 92 | [1],[2]
Impairment Accrued |  |  | 0 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 2 | [1]
Principal balance |  |  | 92 | [1]
Impairment Accrued |  |  | 0 | [1]
Consumer Non Real Estate [Member] | Commercial and Industrial [Member] |  |  |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts | 1 |  |  |
Principal balance | 388 |  |  |
Impairment Accrued | 167 |  |  |
Commercial Real Estate [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts | 3 |  |  |
Pre-Modification Outstanding Principal Balance | 890 |  |  |
Post-Modification Outstanding Principal Balance | 895 | [2] |  |
Impairment Accrued | 0 |  |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts | 2 |  |  |
Principal balance | 861 |  |  |
Impairment Accrued | 0 |  |  |
Commercial Real Estate [Member] | College Housing [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 419 | [1]
Post-Modification Outstanding Principal Balance |  |  | 332 | [1],[2]
Impairment Accrued |  |  | 0 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 1 | [1]
Principal balance |  |  | 250 | [1]
Impairment Accrued |  |  | 0 | [1]
Commercial Real Estate [Member] | Medical Professionals [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 3 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 79 | [1]
Post-Modification Outstanding Principal Balance |  |  | 79 | [1],[2]
Impairment Accrued |  |  | 66 | [1]
Commercial Real Estate [Member] | Other Commercial Real Estate [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 3 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 680 | [1]
Post-Modification Outstanding Principal Balance |  |  | 726 | [1],[2]
Impairment Accrued |  |  | 474 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 3 | [1]
Principal balance |  |  | 687 | [1]
Impairment Accrued |  |  | 474 | [1]
Commercial Real Estate [Member] | General Contractors [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 128 | [1]
Post-Modification Outstanding Principal Balance |  |  | 128 | [1],[2]
Impairment Accrued |  |  | 128 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 2 | [1]
Principal balance |  |  | 128 | [1]
Impairment Accrued |  |  | 128 | [1]
Commercial Non Real Estate [Member] | Commercial and Industrial [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts | 1 |  |  |
Pre-Modification Outstanding Principal Balance | 400 |  |  |
Post-Modification Outstanding Principal Balance | 400 | [2] |  |
Impairment Accrued | 167 |  |  |
Construction Development and Other land [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Amounts of partial charge offs included in troubled debt restructurings |  |  | 789 |
Number of loans that received partial charge-offs |  |  | 1 |
Construction Development and Other land [Member] | Residential [Member] |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |
Number of Contracts |  |  | 3 | [1]
Pre-Modification Outstanding Principal Balance |  |  | 2,474 | [1]
Post-Modification Outstanding Principal Balance |  |  | 1,645 | [1],[2]
Impairment Accrued |  |  | 47 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |
Number of Contracts |  |  | 3 | [1]
Principal balance |  |  | 1,645 | [1]
Impairment Accrued |  |  | $ 46 | [1]
[1] | Segments and classes at December 31, 2011 are reported using the segmentation method in effect for 2011. The Company began reporting under revised segments beginning in 2012.
[2] | Post-modification outstanding recorded investment considers amounts immediately following the modification. Amounts do not reflect balances at the end of the period.

X
- Definition Represents the portion of the recorded investment that was charged off as part of the troubled debt restructuring. + References No definition available. + Details
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- Definition Represents the amount of investment in troubled debt restructures that exceeds fair value, as determined by the impairment measurement, as of the end of the period. + References No definition available. + Details
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- Definition Refers to number of loans previously modified and reported as trouble debt restructurings in prior quarters. + References No definition available. + Details
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- Definition Represents the number of loans for which principal was partially charged off as part of the troubled debt restructuring. + References No definition available. + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524 + Details
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- Definition Amount of investment in financing receivables (after modification) modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524 + Details
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- Definition Amount of investment in financing receivables (before modification) modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953676-111524 + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953682-111524 + Details
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- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=7512638&loc=SL6953682-111524 + Details
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