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OTHER COMPREHENSIVE INCOME (LOSS) - AOCI (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) |  |
Beginning balance | $ (139,974) | $ (2,426)
Change in other comprehensive income (loss) before reclassification | 12,322 | (138,490)
Amounts reclassified from accumulated other comprehensive income | 565 | 942
Net current period other comprehensive income (loss) | 12,887 | (137,548)
Ending balance | (127,087) | (139,974)
Unrealized gains and (Losses) on available- for-sale Securities |  |
Accumulated Other Comprehensive Income (Loss) |  |
Beginning balance | (128,896) | 15,674
Change in other comprehensive income (loss) before reclassification | 10,895 | (144,568)
Amounts reclassified from accumulated other comprehensive income | 1 | (2)
Net current period other comprehensive income (loss) | 10,896 | (144,570)
Ending balance | (118,000) | (128,896)
Retirement plans |  |
Accumulated Other Comprehensive Income (Loss) |  |
Beginning balance | (11,078) | (18,100)
Change in other comprehensive income (loss) before reclassification | 1,427 | 6,078
Amounts reclassified from accumulated other comprehensive income | 564 | 944
Net current period other comprehensive income (loss) | 1,991 | 7,022
Ending balance | $ (9,087) | $ (11,078)

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