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PENSION AND POST-RETIREMENT PLANS - MULTI-EMPLOYER DEFINED BENEFIT PLANS (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Multiemployer Plans |  |  |
Estimated benefit plan withdrawal obligations | $ 155.5 |  |
Pension Benefits | Hawaii Longshore Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 12.9 | $ 12.1 | $ 11.9
Multiemployer Health and Benefit Plans |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 41.2 | 37.7 | 37.7
Multi-employer defined benefit pension plans |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | $ 34.8 | 32.7 | 33.8
Multi-employer defined benefit pension plans | Orange Zone |  |  |
Multiemployer Plans |  |  |
Expected funding deficiency period | 6 years |  |
Multi-employer defined benefit pension plans | Minimum | Green Zone |  |  |
Multiemployer Plans |  |  |
Funded status of multiemployer plan (as a percent) | 80.00% |  |
Multi-employer defined benefit pension plans | Maximum | Red Zone |  |  |
Multiemployer Plans |  |  |
Funded status of multiemployer plan (as a percent) | 65.00% |  |
Multi-employer defined benefit pension plans | Maximum | Yellow Zone |  |  |
Multiemployer Plans |  |  |
Funded status of multiemployer plan (as a percent) | 80.00% |  |
Multi-employer defined benefit pension plans | Maximum | Orange Zone |  |  |
Multiemployer Plans |  |  |
Funded status of multiemployer plan (as a percent) | 80.00% |  |
Multi-employer defined benefit pension plans | American Radio Association Pension Fund | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | $ 1.0 | 1.0 | 1.1
Multi-employer defined benefit pension plans | Master Mates And Pilots Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 3.7 | 3.6 | 3.8
Multi-employer defined benefit pension plans | Masters, Mates and Pilots Adjustable Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 2.1 | 2.0 | 2.1
Multi-employer defined benefit pension plans | MEBA Pension Trust - Defined Benefit Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 4.6 | 4.2 | 4.5
Multi-employer defined benefit pension plans | OCU Pension Trust Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 0.6 | 0.4 | 0.5
Multi-employer defined benefit pension plans | MFOW Supplementary Pension Plan | Yellow Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 0.1 | 0.1 | 0.1
Multi-employer defined benefit pension plans | SIU Pacific District Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 1.3 | 1.3 | 1.5
Multi-employer defined benefit pension plans | Alaska Teamster - Employer Pension Plan | Red Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 3.8 | 3.9 | 4.0
Multi-employer defined benefit pension plans | All Alaska Longshore Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 2.2 | 1.8 | 2.0
Multi-employer defined benefit pension plans | Western Conference of Teamsters Pension Plan | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 2.3 | 2.1 | 2.1
Multi-employer defined benefit pension plans | Western Conference Of Teamsters Supplemental Benefit Trust | Green Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | 0.1 | 0.1 | 0.1
Multi-employer defined benefit pension plans | OPEIU Local 153 Pension Plan | Red Zone |  |  |
Multiemployer Plans |  |  |
Contributions of Matson | $ 0.1 | $ 0.1 | $ 0.1

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