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PENSION AND RETIREMENT PLANS (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 16,782 |  | $ 15,379
SERP |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 16,800 |  | 15,400
Trading (losses) gains related to the SERP assets | 1,400 | $ 337 |
Participant deferrals net of distributions stated at fair value | 19,400 |  | $ 18,000
Change in fair value of liability unrealized gains |  | $ 297 |
Change in fair value of liability unrealized gains (losses) | $ 1,500 |  |

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