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PENSION AND RETIREMENT PLANS (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Fair value of plan assets | $ 17,365 |  | $ 17,365 |  | $ 15,379
Supplemental Executive Retirement Plan (SERP) |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |
Fair value of plan assets | 17,400 |  | 17,400 |  | 15,400
Trading (losses) gains related to the SERP assets | 600 | $ 425 | 2,000 | $ 762 |
Participant deferrals net of distributions stated at fair value |  |  | 20,200 |  | $ 18,000
Change in fair value of liability unrealized gains | $ 600 | $ 519 |  | $ 817 |
Change in fair value of liability unrealized gains (losses) |  |  | $ 2,100 |  |

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