| **Accumulated Other Comprehensive Income (Loss) - Reclassifications (Details) (USD $)**                                                            | 3 Months Ended |
|----------------------------------------------------------------------------------------------------------------------------------------------------|----------------|
||
| **Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]**                                                        |           |   |
| Other income - net realized gains on sales of available for sale securities                                                                        | $ 581,000      | $ 248,000 |
| Interest expense - subordinated debentures and term loans                                                                                          | (1,641,000)    | (725,000) |
| Other expenses - salaries and employee benefits                                                                                                    | (25,301,000)   | (20,791,000) |
| Income tax expense                                                                                                                                 | (4,369,000)    | (4,668,000) |
| NET INCOME                                                                                                                                         | 13,620,000     | 11,865,000 |
| Amount Reclassified from Accumulated Other Comprehensive Income (Loss) for the Period                                                              |           |   |
| **Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]**                                                        |           |   |
| NET INCOME                                                                                                                                         | 154,000        | (601,000) |
| Amount Reclassified from Accumulated Other Comprehensive Income (Loss) for the Period | Unrealized gains (losses) on available for sale securities |           |   |
| **Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]**                                                        |           |   |
| Other income - net realized gains on sales of available for sale securities                                                                        | 581,000        | 248,000 |
| Income tax expense                                                                                                                                 | (203,000)      | (87,000) |
| NET INCOME                                                                                                                                         | 378,000        | 161,000 |
| Amount Reclassified from Accumulated Other Comprehensive Income (Loss) for the Period | Unrealized gains (losses) on cash flow hedges              |           |   |
| **Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]**                                                        |           |   |
| Interest expense - subordinated debentures and term loans                                                                                          | (344,000)      | (188,000) |
| Income tax expense                                                                                                                                 | 120,000        | 66,000 |
| NET INCOME                                                                                                                                         | (224,000)      | (122,000) |
| Amount Reclassified from Accumulated Other Comprehensive Income (Loss) for the Period | Unrealized gains (losses) on defined benefit plans         |           |   |
| **Reclassification Adjustments out of Accumulated Other Comprehensive Income [Line Items]**                                                        |           |   |
| Other expenses - salaries and employee benefits                                                                                                    |      | (985,000) |
| Income tax expense                                                                                                                                 |      | 345,000 |
| NET INCOME                                                                                                                                         | $ 0            | $ (640,000) |

| X                                                                                                                                                                                                          |
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| - Definition
This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of the cost of borrowed funds accounted for as interest expense for debt.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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