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RETIREMENT AND POSTRETIREMENT PLANS - 401(K) Plan - (Details) - 401 K Plan | 12 Months Ended
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Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Maximum contribution by employee, for the calendar year | $ 19,500
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 | $ 9,700,000
Total expense recognized as a component of salaries and employee benefits expense | $ 2,000,000.0
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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