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RETIREMENT AND POSTRETIREMENT PLANS - BNB Bank Pension Plans Assets (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Employee Retirement Plan |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | $ 19,206 | $ 21,303 | $ 22,593
Percentage of cumulative long term return on index | 9.00% |  |
Percentage of cumulative long term return on bonds | 5.00% |  |
Employee Retirement Plan's target allocation, expected annual rate of return | 7.00% | 7.00% |
Employee Retirement Plan | Cash equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | $ 136 | $ 58 |
Employee Retirement Plan | Government |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 19,070 | 21,245 |
Employee Retirement Plan | Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 19,070 | 21,245 |
Employee Retirement Plan | Level 1 | Government |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 19,070 | 21,245 |
Employee Retirement Plan | Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 136 | 58 |
Employee Retirement Plan | Level 2 | Cash equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 136 | 58 |
Pension Plan |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | $ 30,107 | $ 38,170 | $ 38,572
Percentage of cumulative long term return on index | 9.00% |  |
Percentage of cumulative long term return on bonds | 5.00% |  |
Employee Retirement Plan's target allocation, expected annual rate of return | 7.25% | 7.25% |
Pension Plan | Cash equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | $ 1,062 | $ 317 |
Pension Plan | Government |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 29,045 | 37,853 |
Pension Plan | Level 1 |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 29,045 | 37,853 |
Pension Plan | Level 1 | Government |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 29,045 | 37,853 |
Pension Plan | Level 2 |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | 1,062 | 317 |
Pension Plan | Level 2 | Cash equivalents |  |  |
Defined Benefit Plan Disclosure |  |  |
Total Plan Assets | $ 1,062 | $ 317 |

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