| **Loans and Allowance for Loan Losses (Purchased Loans with Deteriorated Credit Quality) (Details) (Granite Corp [Member], USD $)In Thousands, unless otherwise specified** | 3 Months Ended | 6 Months Ended |           |          |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------|----------|
||
| Granite Corp [Member]                                                                                                                                                       |           |           |      |     |   |   |
| **Deterioarted Loans Acquired Movement Schedule [Roll Forward]**                                                                                                            |           |           |      |     |   |   |
| Subtotal before allowance                                                                                                                                                   | $ 149,033      | $ 205,884      | $ 161,652 |     |   |   |
| Accretion                                                                                                                                                                   | 2,415          | 4,191          | 5,079     | 8,394    |   |   |
| Reclassification of loans and adjustments                                                                                                                                   |           |           | (4,180)   |     |   |   |
| Payment received                                                                                                                                                            | (9,524)        | (20,403)       | (20,605)  | (46,331) |   |   |
| Foreclosed and transferred to OREO                                                                                                                                          | 0              | (513)          | (22)      | (1,296)  |   |   |
| Subtotal before allowance                                                                                                                                                   | 141,924        | 189,159        | 141,924   | 189,159  |   |   |
| Subtotal before provision                                                                                                                                                   | (4,123)        | (4,066)        | (4,123)   | (4,066)  |   |   |
| Balance, end of period                                                                                                                                                      | 137,801        | 185,093        | 137,801   | 185,093  | 161,652 | 228,392 |
| **Deteriorated Loans Acquired, Accretable Yield Movement Schedule [Roll Forward]**                                                                                          |           |           |      |     |   |   |
| Future accretion balance, beginning of period                                                                                                                               | 28,327         | 26,096         | 29,987    | 30,299   |   |   |
| Accretion                                                                                                                                                                   | (2,415)        | (4,191)        | (5,079)   | (8,394)  |   |   |
| Increase in future accretion                                                                                                                                                | 1,852          | 6,801          | 2,856     | 6,801    |   |   |
| Future accretion balance, end of period                                                                                                                                     | $ 27,764       | $ 28,706       | $ 27,764  | $ 28,706 |   |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The recorded balance before provision for allowance.  This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Payments received from the date of the transfer of the loan for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Reclassifications of Loans and Adjustments
+ References
No definition available.
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| X                                                                                                                                                                                                    |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of loan foreclosed and transferred to foreclosed assets from the date of the transfer of the loan for loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of decrease from accretion of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.
+ References
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| X                                                                                                                                                                                                                                           |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses).  This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of expense related to loan loss not accounted for as debt securities, with evidence of deterioration of credit quality.
+ References
No definition available.
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