| **Supplemental Cash Flow Disclosures - Non-cash Investing and Financing Activities (Detail) (USD $)In Thousands, unless otherwise specified** | 6 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------------------|----------------|
||
| **Cash paid during the period for:**                                                                                                          |           |   |
| Interest                                                                                                                                      | $ 10,024       | $ 12,990 |
| Income Taxes Paid, Net                                                                                                                        | 3,700          | 2,200 |
| **Non-cash investing and financing activities:**                                                                                              |           |   |
| Loans transferred from held to maturity to held for sale                                                                                      | 3,035          | 20,135 |
| Loans Transferred to Other Real Estate Owned and Repossessions                                                                                | 2,726          | 7,371 |
| Gross increase (decrease) in market value adjustment to securities available for sale                                                         | 22,397         | (27,625) |
| Investments committed to purchase not settled                                                                                                 | 2,732          | 0 |
| Unsettled treasury stock repurchases                                                                                                          | 38             | 0 |
| Unsettled bank owned life insurance proceeds                                                                                                  | $ 1,062        | $ 0 |

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| - Definition
Gross increase in market value adjustment to securities available for sale.
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No definition available.
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| X                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Loans Transferred to Other Real Estate Owned and Repossessions
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No definition available.
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| X                                                                                                                                                                                                                                                                        |
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| - Definition
Unsettled bank owned life insurance proceeds
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| X                                                                                                                                                                                                                                                          |
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| - Definition
Unsettled treasury stock repurchases
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| X                                                                                                                                                                                                    |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of cash paid for interest during the period.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of investments that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.
+ References
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