| **Loans and Allowance for Loan Losses (Evaluation for Impairment) (Details) (USD $)In Thousands, unless otherwise specified** | Sep. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2011 |
|-------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|---------------|---------------|
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | $ 486         |          | $ 1,737       |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 20,835        |          | 22,204        |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 4,066         |          | 5,373         |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 25,387        | 25,085        | 29,314        |               | 30,859        | 38,551        | 39,360 |
| Loans held for investment, individually evaluated for impairment                                                              | 52,320        |          | 77,594        |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 966,229       |          | 871,049       |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 147,852       |          | 192,115       |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 28,741        |          | 36,277        |               |          |          |   |
| Loans held for investment                                                                                                     | 1,195,142     |          | 1,177,035     | [1]           |          |          |   |
| Commercial and agricultural [Member]                                                                                          |          |          |          |               |          |          |   |
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | 0             |          | 282           |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 2,576         |          | 2,432         |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 34            |          | 524           |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 2,610         | 2,192         | 3,238         |               | 5,153         | 7,151         | 5,776 |
| Loans held for investment, individually evaluated for impairment                                                              | 416           |          | 2,334         |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 57,783        |          | 62,704        |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 8,821         |          | 11,533        |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 2,597         |          | 3,133         |               |          |          |   |
| Loans held for investment                                                                                                     | 69,617        |          | 79,704        |               |          |          |   |
| Real estate - construction [Member]                                                                                           |          |          |          |               |          |          |   |
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | 1             |          | 82            |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 4,347         |          | 4,705         |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 747           |          | 200           |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 5,095         | 5,652         | 4,987         |               | 5,983         | 11,320        | 11,995 |
| Loans held for investment, individually evaluated for impairment                                                              | 9,998         |          | 13,533        |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 47,348        |          | 42,199        |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 8,258         |          | 2,285         |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 1,938         |          | 397           |               |          |          |   |
| Loans held for investment                                                                                                     | 67,542        |          | 58,414        |               |          |          |   |
| Real estate - mortgage, 1-4 family residential [Member]                                                                       |          |          |          |               |          |          |   |
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | 446           |          | 607           |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 7,811         |          | 7,383         |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 527           |          | 711           |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 8,784         | 7,400         | 8,701         |               | 9,994         | 8,784         | 8,885 |
| Loans held for investment, individually evaluated for impairment                                                              | 13,060        |          | 18,118        |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 575,490       |          | 496,205       |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 26,661        |          | 34,961        |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 3,051         |          | 4,254         |               |          |          |   |
| Loans held for investment                                                                                                     | 618,262       |          | 553,538       |               |          |          |   |
| Real estate - mortgage, commercial [Member]                                                                                   |          |          |          |               |          |          |   |
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | 39            |          | 766           |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 3,869         |          | 5,473         |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 2,567         |          | 3,388         |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 6,475         | 7,387         | 9,627         |               | 7,058         | 9,218         | 11,063 |
| Loans held for investment, individually evaluated for impairment                                                              | 28,846        |          | 43,609        |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 242,062       |          | 227,760       |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 103,028       |          | 141,974       |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 21,150        |          | 28,493        |               |          |          |   |
| Loans held for investment                                                                                                     | 395,086       |          | 441,836       |               |          |          |   |
| Consumer [Member]                                                                                                             |          |          |          |               |          |          |   |
| **Financing Receivable, Allowance for Credit Losses [Line Items]**                                                            |          |          |          |               |          |          |   |
| ALL, individually evaluated for impairment                                                                                    | 0             |          | 0             |               |          |          |   |
| ALL, collectively evaluated for impairment                                                                                    | 2,232         |          | 2,211         |               |          |          |   |
| ALL, PI loans evluated for credit impairment                                                                                  | 191           |          | 550           |               |          |          |   |
| ALL, PI loans with no credit deterioration                                                                                    | 0             |          | 0             |               |          |          |   |
| Total ALL evaluated for impairment                                                                                            | 2,423         | 2,454         | 2,761         |               | 2,671         | 2,078         | 1,641 |
| Loans held for investment, individually evaluated for impairment                                                              | 0             |          | 0             |               |          |          |   |
| Loans held for investment, collectively evaluated for impairment                                                              | 43,546        |          | 42,181        |               |          |          |   |
| Loans held for investment, PI loans with subsequent credit deterioration                                                      | 1,084         |          | 1,362         |               |          |          |   |
| Loans held for investment, PI loans with no credit deterioration                                                              | 5             |          | 0             |               |          |          |   |
| Loans held for investment                                                                                                     | $ 44,635      |          | $ 43,543      |               |          |          |   |
|                                                                                                                               |
| [1]Derived from audited consolidated financial statements                                                                     |

| X                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were acquired with no credit deterioration.
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| X                                                                                                                                                                                                                                                                                                                                                        |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance of financing receivables that were acquired with deteriorated credit quality.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A valuation allowance for financing receivables that are expected to be uncollectible.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| - Definition
The valuation allowance for financing receivables acquired with deteriorated credit quality.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.
+ References
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| - Definition
The balance of financing receivables that were collectively evaluated for impairment.
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| - Definition
The balance of financing receivables that were individually evaluated for impairment.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 13 -Subparagraph e -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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