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RETIREMENT BENEFITS - Fair Value of Plan Assets by Asset Category (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 769,630 | $ 807,016
Fixed income securities |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 669,645 | 708,088
Equity securities—US |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 51,603 | 48,237
Equity securities—International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 24,127 | 24,512
Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 24,255 | $ 26,179

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