| **Loans and Allowance for Loan Losses (Impaired Loans, Average Recorded Investment and Interest Income Recognized) (Details) - USD ($) $ in Thousands** | 3 Months Ended | 9 Months Ended |          |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|----------|
||
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | $ 24,397       | $ 30,382       | $ 23,862 | $ 31,372 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 89             | 59             | 291      | 353 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 3,509          | 7,840          | 5,243    | 7,919 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 10             | 50             | 95       | 198 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 27,906         | 38,222         | 29,105   | 39,291 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 99             | 109            | 386      | 551 |   |
| Restructured loans                                                                                                                                      | 18,500         |           | 18,500   |   | $ 19,400 |
| Commercial and agricultural [Member]                                                                                                                    |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | 404            | 222            | 439      | 222 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 0              | 0              | 0        | 0 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 0              | 0              | 0        | 0 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 404            | 222            | 439      | 222 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 0              | 0              | 0        | 0 |   |
| Real estate - construction [Member]                                                                                                                     |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | 878            | 2,865          | 1,093    | 2,936 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 8              | 8              | 26       | 29 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 0              | 0              | 0        | 0 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 878            | 2,865          | 1,093    | 2,936 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 8              | 8              | 26       | 29 |   |
| Real estate - mortgage, 1-4 family residential [Member]                                                                                                 |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | 8,786          | 8,253          | 7,937    | 8,400 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 31             | 23             | 85       | 87 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 3,509          | 3,413          | 3,966    | 3,440 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 10             | 12             | 43       | 45 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 12,295         | 11,666         | 11,903   | 11,840 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 41             | 35             | 128      | 132 |   |
| Real estate - mortgage, commercial [Member]                                                                                                             |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | 14,329         | 19,042         | 14,393   | 19,814 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 50             | 28             | 180      | 237 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 0              | 4,427          | 1,277    | 4,479 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 0              | 38             | 52       | 153 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 14,329         | 23,469         | 15,670   | 24,293 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 50             | 66             | 232      | 390 |   |
| Consumer [Member]                                                                                                                                       |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| With no related allowance recorded, average recorded investment                                                                                         | 0              | 0              | 0        | 0 |   |
| With no related allowance recorded, interest income recognized                                                                                          | 0              | 0              | 0        | 0 |   |
| With an allowance recorded, average recorded investment                                                                                                 | 0              | 0              | 0        | 0 |   |
| With an allowance recorded, interest income recognized                                                                                                  | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, Average Recorded Investment                                                                                              | 0              | 0              | 0        | 0 |   |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                       | 0              | $ 0            | 0        | $ 0 |   |
| Performing Financial Instruments [Member]                                                                                                               |           |           |     |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                         |           |           |     |   |   |
| Restructured loans                                                                                                                                      | $ 14,200       |           | $ 14,200 |   | $ 14,100 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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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
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired.
+ References
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