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Allowance for Loan Losses, Nonperforming Assets and Impaired Loans, Troubled Debt Restructurings (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 Modifications [Abstract] |  |  |  |  |  |
Number of Contracts | 2 | 4 | [1] | 10 | 14 | [1]
Pre-Modification Outstanding Principal Balance | $ 231 | $ 2,920 | [1] | $ 1,816 | $ 4,078 | [1]
Post-Modification Outstanding Principal Balance | 231 | 2,820 | [1] | 1,844 | 3,880 | [1]
Troubled debt restructuring total amount of unpaid principal balance to date | 4,275 | 8,605 |  | 4,275 | 8,605 |
Trouble debt restructuring financiing receivable amount of specific allocations to date | 284 | 1,372 |  | 284 | 1,372 |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts | 4 | 3 |  | 4 | 7 |
Principal Balance | 1,041 | 520 |  | 1,041 | 1,320 |
Number of days delay beyond which restructured loans are secured by real estate, minimum (in days) |  |  |  | 90 days |  |
Consumer Real Estate [Member] | Closed-end first liens [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts | 1 |  |  | 5 |  |
Pre-Modification Outstanding Principal Balance | 38 |  |  | 383 |  |
Post-Modification Outstanding Principal Balance | 38 |  |  | 402 |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts | 1 |  |  | 1 |  |
Principal Balance | 96 |  |  | 96 |  |
Consumer Real Estate [Member] | Closed end Consumer Real Estate [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  |  |  |  | 1 | [1]
Pre-Modification Outstanding Principal Balance |  |  |  |  | 75 | [1]
Post-Modification Outstanding Principal Balance |  |  |  |  | 75 | [1]
Consumer Real Estate [Member] | Closed-end junior liens [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  |  |  | 1 |  |
Pre-Modification Outstanding Principal Balance |  |  |  | 143 |  |
Post-Modification Outstanding Principal Balance |  |  |  | 147 |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts | 1 |  |  | 1 |  |
Principal Balance | 84 |  |  | 84 |  |
Consumer Real Estate [Member] | 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]
Construction Development and Other land [Member] | Residential [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  | 1 | [1] |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  | 2,400 | [1] |  | 2,634 | [1]
Post-Modification Outstanding Principal Balance |  | 2,300 | [1] |  | 2,534 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts |  | 0 |  |  | 1 |
Principal Balance |  | 0 |  |  | 234 |
Commercial Real Estate [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Partial charge-off on loans |  |  |  | 109 |  |
Commercial Real Estate [Member] | Medical Professionals [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  |  |  |  | 3 | [1]
Pre-Modification Outstanding Principal Balance |  |  |  |  | 73 | [1]
Post-Modification Outstanding Principal Balance |  |  |  |  | 73 | [1]
Commercial Real Estate [Member] | College Housing [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  |  |  |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  |  |  |  | 422 | [1]
Post-Modification Outstanding Principal Balance |  |  |  |  | 332 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts |  | 0 |  |  | 1 |
Principal Balance |  | 0 |  |  | 255 |
Commercial Real Estate [Member] | Commercial real estate, other [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  | 1 | [1] |  | 3 | [1]
Pre-Modification Outstanding Principal Balance |  | 392 | [1] |  | 696 | [1]
Post-Modification Outstanding Principal Balance |  | 392 | [1] |  | 688 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts |  | 1 |  |  | 3 |
Principal Balance |  | 392 |  |  | 700 |
Commercial Real Estate [Member] | General Contractors [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts |  | 2 | [1] |  | 2 | [1]
Pre-Modification Outstanding Principal Balance |  | 128 | [1] |  | 128 | [1]
Post-Modification Outstanding Principal Balance |  | 128 | [1] |  | 128 | [1]
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts |  | 2 |  |  | 2 |
Principal Balance |  | 128 |  |  | 131 |
Commercial Real Estate [Member] | Commercial real estate, owner occupied [Member] |  |  |  |  |  |
Financing Receivable Modifications [Abstract] |  |  |  |  |  |
Number of Contracts | 1 |  |  | 3 |  |
Pre-Modification Outstanding Principal Balance | 193 |  |  | 890 |  |
Post-Modification Outstanding Principal Balance | 193 |  |  | 895 |  |
Financing Receivable Modifications Subsequent Default [Abstract] |  |  |  |  |  |
Number of Contracts | 2 |  |  | 2 |  |
Principal Balance | 861 |  |  | 861 |  |
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 |  |
[1] | Segments at September 30, 2011 are reported using the segmentation method in effect for 2011. The Company began reporting under revised segments beginning in 2012.

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- Definition Amount of investment in financing receivables (after modification) modified during the period by troubled debt restructurings. + References No definition available. + 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 during the period. + References No definition available. + 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 during the period. + References No definition available. + Details
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- Definition The amount of the outstanding recorded investment related to 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 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554 + Details
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- Definition Reflects the amount of the write-down related to a troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18845-111554 + Details
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