| **Loans (Impaired Loans, Average Recorded Investment and Interest Income Recognized) (Details) (USD $)In Thousands, unless otherwise specified** | 3 Months Ended | 6 Months Ended |
|--------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|
||
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| Number of loans sold                                                                                                                             | 0              | 6              | 0 | 8 |
| With no related alowance recorded, average recorded investment                                                                                   | $ 54,039       | $ 63,662       | $ 54,804 | $ 64,307 |
| With no related allowance recorded, interest income recognized                                                                                   | 35             | 184            | 185 | 231 |
| With an allowance recorded, average recorded investment                                                                                          | 6,064          | 43,601         | 6,109 | 42,508 |
| With an allowance recorded, interest income recognized                                                                                           | 4              | 247            | 11 | 275 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 60,103         | 107,263        | 60,913 | 106,815 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 39             | 431            | 196 | 506 |
| Recorded investment of loans sold                                                                                                                | 0              | 1,715          | 0 | 5,665 |
| Contract pricing of loans sold                                                                                                                   | 0              | 1,746          | 0 | 5,946 |
| Commercial and agricultural [Member]                                                                                                             |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| With no related alowance recorded, average recorded investment                                                                                   | 1,398          | 2,170          | 1,414 | 2,651 |
| With no related allowance recorded, interest income recognized                                                                                   | 1              | 3              | 8 | 10 |
| With an allowance recorded, average recorded investment                                                                                          | 107            | 1,790          | 107 | 1,729 |
| With an allowance recorded, interest income recognized                                                                                           | 0              | 0              | 0 | 0 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 1,505          | 3,960          | 1,521 | 4,380 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 1              | 3              | 8 | 10 |
| Real estate - construction [Member]                                                                                                              |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| With no related alowance recorded, average recorded investment                                                                                   | 9,513          | 10,918         | 9,705 | 12,166 |
| With no related allowance recorded, interest income recognized                                                                                   | 0              | 30             | 0 | 34 |
| With an allowance recorded, average recorded investment                                                                                          | 219            | 16,567         | 220 | 14,308 |
| With an allowance recorded, interest income recognized                                                                                           | 3              | 7              | 6 | 9 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 9,732          | 27,485         | 9,925 | 26,474 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 3              | 37             | 6 | 43 |
| Real estate - mortgage, 1-4 family residential [Member]                                                                                          |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| With no related alowance recorded, average recorded investment                                                                                   | 12,662         | 15,944         | 12,643 | 17,071 |
| With no related allowance recorded, interest income recognized                                                                                   | 9              | 60             | 33 | 66 |
| With an allowance recorded, average recorded investment                                                                                          | 1,662          | 8,760          | 1,682 | 10,862 |
| With an allowance recorded, interest income recognized                                                                                           | 1              | 76             | 4 | 94 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 14,324         | 24,704         | 14,325 | 27,933 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 10             | 136            | 37 | 160 |
| Real estate - mortgage, commercial [Member]                                                                                                      |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| With no related alowance recorded, average recorded investment                                                                                   | 30,466         | 33,630         | 31,042 | 31,720 |
| With no related allowance recorded, interest income recognized                                                                                   | 25             | 76             | 144 | 106 |
| With an allowance recorded, average recorded investment                                                                                          | 3,912          | 15,832         | 3,933 | 15,177 |
| With an allowance recorded, interest income recognized                                                                                           | 0              | 151            | 0 | 159 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 34,378         | 49,462         | 34,975 | 46,897 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 25             | 227            | 144 | 265 |
| Consumer [Member]                                                                                                                                |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| With no related alowance recorded, average recorded investment                                                                                   | 0              | 1,000          | 0 | 699 |
| With no related allowance recorded, interest income recognized                                                                                   | 0              | 15             | 0 | 15 |
| With an allowance recorded, average recorded investment                                                                                          | 164            | 652            | 167 | 432 |
| With an allowance recorded, interest income recognized                                                                                           | 0              | 13             | 1 | 13 |
| Impaired Financing Receivable, Average Recorded Investment                                                                                       | 164            | 1,652          | 167 | 1,131 |
| Impaired Financing Receivable, Interest Income, Cash Basis Method                                                                                | 0              | 28             | 1 | 28 |
| Real estate - mortgage, 1-4 family residential [Member]                                                                                          |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| Number of loans sold                                                                                                                             |           | 6              |   | 7 |
| Recorded investment of loans sold                                                                                                                |           | 1,715          |   | 1,865 |
| Contract pricing of loans sold                                                                                                                   |           | 1,746          |   | 1,896 |
| Real estate - mortgage, commercial [Member]                                                                                                      |           |           |   |   |
| **Financing Receivable, Impaired [Line Items]**                                                                                                  |           |           |   |   |
| Number of loans sold                                                                                                                             |           |           |   | 1 |
| Recorded investment of loans sold                                                                                                                |           | 0              |   | 3,800 |
| Contract pricing of loans sold                                                                                                                   |           | $ 0            |   | $ 4,050 |

| X                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of loans sold during the period.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate sale (contract price) amount of loans receivable that were sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate carrying amount of loans receivable that were sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).
+ References
No definition available.
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| X                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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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