| **Revenue Recognition In-Scope and Out-of-Scope Revenue Streams (Details) - USD ($) $ in Thousands** | 3 Months Ended |
|------------------------------------------------------------------------------------------------------|----------------|
||
| Trust income                                                                                         | $ 2,713        | $ 2,516 |
| Service charges on deposit accounts                                                                  | 4,615          | 4,047 |
| Insurance and retail brokerage commissions                                                           | 2,272          | 2,172 |
| Card-related interchange income                                                                      | 6,490          | 6,427 |
| Derivatives mark to market                                                                           | 347            | 1,430 |
| Gain on sale of loans and other assets.                                                              | 2,319          | 1,690 |
| Other income                                                                                         | 1,975          | 1,924 |
| Noninterest Income                                                                                   | 23,976         | 27,355 |
| In-Scope of Topic 606 [Member]                                                                       |           |   |
| Trust income                                                                                         | 2,713          | 2,516 |
| Service charges on deposit accounts                                                                  | 4,615          | 4,047 |
| Insurance and retail brokerage commissions                                                           | 2,272          | 2,172 |
| Card-related interchange income                                                                      | 6,490          | 6,427 |
| Gain on sale of loans and other assets.                                                              | 43             | 169 |
| Other income                                                                                         | 975            | 980 |
| Noninterest Income                                                                                   | 17,108         | 16,311 |
| Out-Of-Scope of Topic 606 [Member]                                                                   |           |   |
| Noninterest Income                                                                                   | $ 6,868        | $ 11,044 |

| X                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fees and Commissions on Debit Cards
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Fees and Commissions on Depositor Accounts
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| X                                                                                                                                                                                                                                                                                       |
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| - Definition
Fees and Commissions on Trust and Fiduciary Accounts
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.
+ References
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| - Definition
Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.
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| - Definition
Amount of revenue earned, classified as other, excluding interest income.
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