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RETIREMENT AND POSTRETIREMENT PLANS - 401(K) Plan - (Details) - 401 K Plan - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Maximum contribution by employee, for the calendar year |  |  | $ 23,000 |
Percentage of match for first 1% of employee contributions |  |  | 100.00% |
Percentage of employee contribution on which 100% match by employer |  |  | 1.00% |
Percentage of match on next 1% of employee contributions |  |  | 50.00% |
Common stock within the accounts of participants | $ 4,700,000 |  | $ 4,700,000 |
Total expense recognized as a component of salaries and employee benefits expense | $ 796,000 | $ 582,000 | $ 1,700,000 | $ 1,500,000
Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of employee contribution on which 50% match by employer |  |  | 6.00% |
Maximum Percentage of participating employee contribution |  |  | 3.50% |

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