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RETIREMENT AND POSTRETIREMENT PLANS - 401(K) Plan - (Details) - 401 K Plan - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Jun. 30, 2022 | Sep. 30, 2023 | Sep. 30, 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 | $ 4,800,000 |  | $ 4,800,000 |
Total expense recognized as a component of salaries and employee benefits expense | $ 513,000 | $ 509,000 | $ 2,000,000.0 | $ 1,800,000
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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- Definition Value of all classes of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares exclude common shares repurchased by the entity and held as treasury shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-04(16)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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