| **Loans (Impaired Loans Disclosure) (Details) (USD $)In Thousands, unless otherwise specified** | Mar. 31, 2013 | Dec. 31, 2012 |
|-------------------------------------------------------------------------------------------------|---------------|---------------|
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | $ 56,985      | $ 62,282      |
| With an allowance recorded, recorded investment                                                 | 16,097        | 15,312        |
| Impaired Financing Receivable, Recorded Investment                                              | 73,082        | 77,594        |
| With no related allowance recorded, unpaid principal balance                                    | 74,277        | 80,510        |
| With an allowance recorded, unpaid principal balance                                            | 19,357        | 18,904        |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 93,634        | 99,414        |
| Related allowance                                                                               | 3,129         | 1,737         |
| Purchased impaired loans with subsequent deterioration                                          | 176,048       | 192,115       |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 178,265       | 196,617       |
| Purchased impaired loans with subsequent deterioration, related allowance                       | 5,373         | 5,373         |
| Commercial and agricultural [Member]                                                            |          |          |
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | 875           | 1,755         |
| With an allowance recorded, recorded investment                                                 | 917           | 579           |
| Impaired Financing Receivable, Recorded Investment                                              | 1,792         | 2,334         |
| With no related allowance recorded, unpaid principal balance                                    | 1,413         | 2,608         |
| With an allowance recorded, unpaid principal balance                                            | 917           | 602           |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 2,330         | 3,210         |
| Related allowance                                                                               | 227           | 282           |
| Purchased impaired loans with subsequent deterioration                                          | 9,930         | 11,533        |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 9,800         | 11,728        |
| Purchased impaired loans with subsequent deterioration, related allowance                       | 545           | 524           |
| Real estate - construction [Member]                                                             |          |          |
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | 8,953         | 11,875        |
| With an allowance recorded, recorded investment                                                 | 2,080         | 1,658         |
| Impaired Financing Receivable, Recorded Investment                                              | 11,033        | 13,533        |
| With no related allowance recorded, unpaid principal balance                                    | 14,910        | 18,553        |
| With an allowance recorded, unpaid principal balance                                            | 2,159         | 1,843         |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 17,069        | 20,396        |
| Related allowance                                                                               | 501           | 82            |
| Purchased impaired loans with subsequent deterioration                                          | 1,986         | 2,285         |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 1,924         | 2,236         |
| Purchased impaired loans with subsequent deterioration, related allowance                       | 197           | 200           |
| Real estate - mortgage, 1-4 family residential [Member]                                         |          |          |
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | 14,310        | 16,437        |
| With an allowance recorded, recorded investment                                                 | 4,599         | 1,681         |
| Impaired Financing Receivable, Recorded Investment                                              | 18,909        | 18,118        |
| With no related allowance recorded, unpaid principal balance                                    | 17,861        | 20,764        |
| With an allowance recorded, unpaid principal balance                                            | 5,360         | 1,745         |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 23,221        | 22,509        |
| Related allowance                                                                               | 1,317         | 607           |
| Purchased impaired loans with subsequent deterioration                                          | 33,174        | 34,961        |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 33,776        | 35,802        |
| Purchased impaired loans with subsequent deterioration, related allowance                       | 730           | 711           |
| Real estate - mortgage, commercial [Member]                                                     |          |          |
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | 32,847        | 32,215        |
| With an allowance recorded, recorded investment                                                 | 8,501         | 11,394        |
| Impaired Financing Receivable, Recorded Investment                                              | 41,348        | 43,609        |
| With no related allowance recorded, unpaid principal balance                                    | 40,093        | 38,585        |
| With an allowance recorded, unpaid principal balance                                            | 10,921        | 14,714        |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 51,014        | 53,299        |
| Related allowance                                                                               | 1,084         | 766           |
| Purchased impaired loans with subsequent deterioration                                          | 129,655       | 141,974       |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 131,753       | 145,704       |
| Purchased impaired loans with subsequent deterioration, related allowance                       | 3,351         | 3,388         |
| Consumer [Member]                                                                               |          |          |
| **Financing Receivable, Impaired [Line Items]**                                                 |          |          |
| With no related allowance recorded, recorded investment                                         | 0             | 0             |
| With an allowance recorded, recorded investment                                                 | 0             | 0             |
| Impaired Financing Receivable, Recorded Investment                                              | 0             | 0             |
| With no related allowance recorded, unpaid principal balance                                    | 0             | 0             |
| With an allowance recorded, unpaid principal balance                                            | 0             | 0             |
| Impaired Financing Receivable, Unpaid Principal Balance                                         | 0             | 0             |
| Related allowance                                                                               | 0             | 0             |
| Purchased impaired loans with subsequent deterioration                                          | 1,303         | 1,362         |
| Purchased impaired loans with subsequent credit deterioration, unpaid principal balance         | 1,012         | 1,147         |
| Purchased impaired loans with subsequent deterioration, related allowance                       | $ 550         | $ 550         |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Certain Loans and Debt Securities Acquired in Transfer, with Related Allowance for Credit Losses Due to Subsequent Impairment, Unpaid Principal Balance
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
For loans and debt securities, 1) for which at acquisition it was probable that the investor would be unable to collect all contractually required payments receivable, and 2) for which it is further probable that the investor will not be able to collect all cash flows expected at acquisition (plus any additional cash flows expected due to changes in estimate after acquisition), the allowance for credit losses recorded to reflect the impairment since acquisition.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The recorded amount of loans and debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it was probable, at acquisition, that the investor would be unable to collect all contractually required payments receivable. They are deemed to be impaired since the acquisition and an allowance for credit losses has been recorded. Disclosure is gross of the allowance.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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 allowance for credit losses related to recorded investment.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.
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| - Definition
Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.
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| - Definition
Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.
+ References
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