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RETIREMENT AND POSTRETIREMENT PLANS - 401(K) Plan - (Details) - 401 K Plan - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |
Maximum contribution by employee, for the calendar year | $ 22,500 |
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 | $ 6,300,000 | $ 7,800,000
Total expense recognized as a component of salaries and employee benefits expense | $ 2,500,000 | $ 2,300,000
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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