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PENSION AND POST-RETIREMENT PLANS (Tables) | 12 Months Ended
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Dec. 31, 2021
PENSION AND POST-RETIREMENT PLANS |
Schedule of the Company's target and actual asset allocations | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Asset Categories |  | Target |  | 2021 |  | 2020 |
Domestic equity securities |  | 53 | % | 61 | % | 60 | %
International equity securities |  | 15 | % | 16 | % | 17 | %
Debt securities |  | 22 | % | 15 | % | 17 | %
Real estate |  | 5 | % | 6 | % | 5 | %
Other and cash |  | 5 | % | 2 | % | 1 | %
Total |  | 100 | % | 100 | % | 100 | %
Schedule of the Company's actual return on plan assets | ​
​ | ​ | ​ | ​
Actual Return on Plan Assets |  | Returns |
One-year return |  | 14.9 | %
Three-year return |  | 16.4 | %
Five-year return |  | 11.1 | %
Long-term average return (since plan inception in 1989) |  | 8.7 | %
Schedule of the fair values of the Company's pension plan assets, by asset category | The fair values of the Company’s pension plan assets at December 31, 2021 and 2020 by asset category were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fair Value Measurements at December 31, 2021 |
​ |  | ​ | ​ |  | Quoted Prices in |  | Significant |  | Significant |
​ | ​ | ​ | ​ | ​ | Active Markets | ​ | Observable | ​ | Unobservable |
Asset Category (in millions) | ​ | Total | ​ | (Level 1) | ​ | Inputs (Level 2) | ​ | Inputs (Level 3) |
Cash | ​ | $ | 10.7 | ​ | $ | 10.7 | ​ | $ | — | ​ | $ | — | ​
Equity securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. large-cap | ​ |  | 80.9 | ​ |  | 80.9 | ​ |  | — | ​ |  | — | ​
U.S. mid- and small-cap | ​ |  | 61.7 | ​ |  | 61.7 | ​ |  | — | ​ |  | — | ​
International large-cap | ​ |  | 7.5 | ​ |  | 7.5 | ​ |  | — | ​ |  | — | ​
Fixed income securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasuries | ​ |  | 9.6 | ​ |  | — | ​ |  | 9.6 | ​ |  | — | ​
Investment grade U.S. corporate bonds | ​ | ​ | 24.5 | ​ |  | — | ​ |  | 24.5 | ​ |  | — | ​
High-yield U.S. corporate bonds / Non-U.S. Bonds | ​ |  | 0.2 | ​ |  | — | ​ |  | 0.2 | ​ |  | — | ​
Total | ​ | ​ | 195.1 | ​ | $ | 160.8 | ​ | $ | 34.3 | ​ | $ | — | ​
Investment measured at NAV (1) | ​ | ​ | 44.4 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Total plan assets | ​ | $ | 239.5 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fair Value Measurements at December 31, 2020 |
​ |  | ​ | ​ |  | Quoted Prices in |  | Significant |  | Significant |
​ | ​ | ​ | ​ | ​ | Active Markets | ​ | Observable | ​ | Unobservable |
Asset Category (in millions) | ​ | Total | ​ | (Level 1) | ​ | Inputs (Level 2) | ​ | Inputs (Level 3) |
Cash | ​ | $ | 3.8 | ​ | $ | 3.8 | ​ | $ | — | ​ | $ | — | ​
Equity securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. large-cap | ​ |  | 71.3 | ​ |  | 28.9 | ​ |  | 42.4 | ​ |  | — | ​
U.S. mid- and small-cap | ​ |  | 54.3 | ​ |  | 36.2 | ​ |  | 18.1 | ​ |  | — | ​
International large-cap | ​ |  | 7.0 | ​ |  | — | ​ |  | 7.0 | ​ |  | — | ​
Fixed income securities: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
U.S. Treasuries | ​ |  | 12.0 | ​ |  | — | ​ |  | 12.0 | ​ |  | — | ​
Investment grade U.S. corporate bonds | ​ |  | 22.5 | ​ |  | — | ​ |  | 22.5 | ​ |  | — | ​
Total | ​ | ​ | 170.9 | ​ | $ | 68.9 | ​ | $ | 102.0 | ​ | $ | — | ​
Investment measured at NAV (1) | ​ | ​ | 41.9 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Total plan assets | ​ | $ | 212.8 | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
(1) | Real estate and private equity funds for which fair value is measured using the NAV per share as a practical expedient are not leveled within the fair value hierarchy and are included as a reconciling item to total plan assets.
Schedule of change in benefit obligation and plan assets | The status of the funded qualified defined benefit pension plans and the unfunded post-retirement benefit plans at December 31, 2021 and 2020 are shown below:
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Post-retirement |
​ | ​ | Pension Benefits | ​ | Benefits |
​ | ​ | December 31, | ​ | December 31, | ​
(In millions) |  | 2021 |  | 2020 |  | 2021 |  | 2020 |
Change in Benefit Obligation: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Benefit obligation at beginning of year | ​ | $ | 263.1 | ​ | $ | 239.9 | ​ | $ | 29.1 | ​ | $ | 26.0 | ​
Service cost | ​ |  | 4.8 | ​ |  | 5.1 | ​ |  | 0.7 | ​ |  | 0.5 | ​
Interest cost | ​ |  | 6.4 | ​ |  | 7.9 | ​ |  | 0.7 | ​ |  | 0.8 | ​
Participant contributions | ​ |  | — | ​ |  | — | ​ |  | 0.8 | ​ |  | 0.8 | ​
Actuarial (gain) loss | ​ |  | (10.7) | ​ |  | 23.9 | ​ |  | 0.1 | ​ |  | 2.7 | ​
Benefits paid, net of subsidies received | ​ |  | (13.0) | ​ |  | (12.5) | ​ |  | (2.1) | ​ |  | (1.7) | ​
Expenses paid | ​ |  | (1.1) | ​ |  | (1.2) | ​ |  | — | ​ |  | — | ​
Benefit obligation at end of year | ​ | ​ | 249.5 | ​ | ​ | 263.1 | ​ | ​ | 29.3 | ​ | ​ | 29.1 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Change in Plan Assets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Fair value of plan assets at beginning of year | ​ | ​ | 212.8 | ​ | ​ | 194.8 | ​ | ​ | — | ​ | ​ | — | ​
Actual return on plan assets | ​ |  | 31.2 | ​ |  | 22.7 | ​ |  | — | ​ |  | — | ​
Participant contributions | ​ |  | — | ​ |  | — | ​ |  | 0.8 | ​ |  | 0.8 | ​
Employer contributions | ​ |  | 9.0 | ​ |  | 9.0 | ​ |  | 1.3 | ​ |  | 0.9 | ​
Benefits paid, net of subsidies received | ​ |  | (13.0) | ​ |  | (12.5) | ​ |  | (2.1) | ​ |  | (1.7) | ​
Expenses paid | ​ |  | (1.1) | ​ |  | (1.2) | ​ |  | — | ​ |  | — | ​
Fair value of plan assets at end of year | ​ |  | 238.9 | ​ |  | 212.8 | ​ |  | — | ​ |  | — | ​
Funded Status and Recognized Liability | ​ | $ | (10.6) | ​ | $ | (50.3) | ​ | $ | (29.3) | ​ | $ | (29.1) | ​
Schedule of amounts recognized on the consolidated balance sheets and in accumulated other comprehensive loss | Qualified pension and post-retirement benefits plans liabilities recognized in the Consolidated Balance Sheets and expenses recognized in accumulated other comprehensive income (loss) at December 31, 2021 and 2020 were as follows:
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | Post-retirement |
​ | ​ | Pension Benefits | ​ | Benefits |
​ | ​ | December 31, | ​ | December 31, | ​
(In millions) |  | 2021 |  | 2020 |  | 2021 |  | 2020 |
Non-current assets | ​ | $ | 1.3 | ​ | $ | 1.0 | ​ | $ | — | ​ | $ | — | ​
Current liabilities | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.9) | ​ | ​ | (1.0) | ​
Non-current liabilities, net | ​ |  | (11.9) | ​ |  | (51.3) | ​ |  | (28.4) | ​ |  | (28.1) | ​
Total | ​ | $ | (10.6) | ​ | $ | (50.3) | ​ | $ | (29.3) | ​ | $ | (29.1) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Net loss, net of taxes | ​ | $ | (39.9) | ​ | $ | (64.2) | ​ | $ | (3.7) | ​ | $ | (4.4) | ​
Prior service credit, net of taxes | ​ |  | 0.8 | ​ |  | 2.5 | ​ |  | 13.9 | ​ |  | 16.6 | ​
Total | ​ | $ | (39.1) | ​ | $ | (61.7) | ​ | $ | 10.2 | ​ | $ | 12.2 | ​
Schedule of information for qualified pension plans with an accumulated benefit obligation in excess of plan assets | The information for qualified defined benefit pension plans with an accumulated benefit obligation in excess of plan assets at December 31, 2021 and 2020 are shown below: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
(In millions) |  | 2021 |  | 2020 |
Projected benefit obligation | ​ | $ | 247.8 | ​ | $ | 261.4 | ​
Accumulated benefit obligation | ​ | $ | 247.4 | ​ | $ | 260.9 | ​
Fair value of plan assets | ​ | $ | 235.8 | ​ | $ | 210.0 | ​
Schedule of components of the net periodic benefit cost and other changes in plan assets and benefit obligations recognized in other comprehensive income | Components of the net periodic benefit cost and other amounts recognized in other comprehensive income (loss) for the qualified pension plans and the post-retirement benefit plans during 2021, 2020 and 2019 were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Pension Benefits | ​ | Post-retirement Benefits |
​ | ​ | December 31, | ​ | December 31, | ​
(In millions) |  | 2021 |  | 2020 |  | 2019 |  | 2021 |  | 2020 |  | 2019 |
Components of Net Periodic Benefit Cost (Benefit): | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Service cost | ​ | $ | 4.8 | ​ | $ | 5.1 | ​ | $ | 4.7 | ​ | $ | 0.7 | ​ | $ | 0.5 | ​ | $ | 0.4 | ​
Interest cost | ​ |  | 6.4 | ​ |  | 7.9 | ​ |  | 9.3 | ​ |  | 0.7 | ​ |  | 0.8 | ​ |  | 0.9 | ​
Expected return on plan assets | ​ |  | (14.7) | ​ |  | (14.0) | ​ |  | (11.9) | ​ |  | — | ​ |  | — | ​ |  | — | ​
Amortization of net loss (gain) | ​ |  | 5.2 | ​ |  | 4.5 | ​ |  | 5.2 | ​ |  | 1.0 | ​ |  | 0.5 | ​ |  | (0.1) | ​
Amortization of prior service credit | ​ |  | (2.3) | ​ |  | (2.3) | ​ |  | (2.3) | ​ |  | (3.7) | ​ |  | (3.7) | ​ |  | (3.8) | ​
Net periodic benefit cost | ​ | ​ | (0.6) | ​ | ​ | 1.2 | ​ | ​ | 5.0 | ​ | ​ | (1.3) | ​ | ​ | (1.9) | ​ | ​ | (2.6) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income, net of tax: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Net (gain) loss | ​ | ​ | (20.4) | ​ | ​ | 11.4 | ​ | ​ | (1.7) | ​ | ​ | — | ​ | ​ | 2.0 | ​ | ​ | 2.5 | ​
Amortization of net (loss) gain | ​ |  | (3.9) | ​ |  | (3.4) | ​ |  | (3.9) | ​ |  | (0.7) | ​ |  | (0.3) | ​ |  | 0.2 | ​
Amortization of prior service credit | ​ |  | 1.7 | ​ |  | 1.7 | ​ |  | 1.7 | ​ |  | 2.8 | ​ |  | 2.8 | ​ |  | 2.8 | ​
Total recognized in other comprehensive loss (income) | ​ | ​ | (22.6) | ​ | ​ | 9.7 | ​ | ​ | (3.9) | ​ | ​ | 2.1 | ​ | ​ | 4.5 | ​ | ​ | 5.5 | ​
Total recognized in net periodic benefit cost and other comprehensive loss (income) | ​ | $ | (23.2) | ​ | $ | 10.9 | ​ | $ | 1.1 | ​ | $ | 0.8 | ​ | $ | 2.6 | ​ | $ | 2.9 | ​
Schedule of weighted average assumptions used to determine benefit information | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Pension Benefits | ​ | Post-retirement Benefits |
​ | ​ | December 31, | ​ | December 31, | ​
​ |  | 2021 |  | 2020 |  | 2019 |  | 2021 |  | 2020 |  | 2019 |
Discount rate (1) |  | 2.90 | % | 2.50 | % | 3.40 | % | 3.00 | % | 2.70 | % | 3.50 | %
Expected return on plan assets |  | 7.00 | % | 7.25 | % | 7.50 | % | ​ | ​ | ​ | ​ | ​ | ​
Rate of compensation increase |  | 3.00 | % | 3.00 | % | 3.00 | % | 3.00 | % | 3.00 | % | 3.00 | %
Cash balance interest credit rate | ​ | 1.5 % - 3.25 | % | 0.75 % - 3.25 | % | 1.75 % - 3.75 | % | ​ | ​ | ​ | ​ | ​ | ​
Immediate health care cost trend rate: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Pre-65 group | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 5.70 | % | 5.30 | % | 5.70 | %
Post-65 group | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 5.80 | % | 5.40 | % | 5.90 | %
Ultimate health care cost trend rate | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 4.00 | % | 4.40 | % | 4.40 | %
Year ultimate health care cost trend rate is reached: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Pre-65 group | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 2045 | ​ | 2037 | ​ | 2037 | ​
Post-65 group | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 2045 | ​ | 2036 | ​ | 2036 | ​
(1) | The Company derives a single equivalent rate utilizing a yield curve constructed from a portfolio of high-quality corporate bonds with various maturities.
Schedule of amounts recognized on balance sheet and accumulated comprehensive income | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Non-qualified |
​ |  | Pension Benefits |
​ |  | December 31, | ​
(In millions) | ​ | 2021 |  | 2020 |
Current liabilities | ​ | $ | (1.8) | ​ | $ | (1.7) | ​
Non-current liabilities, net | ​ | ​ | (3.0) | ​ | ​ | (2.6) | ​
Total | ​ | $ | (4.8) | ​ | $ | (4.3) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Net loss, net of taxes | ​ | $ | (0.7) | ​ | $ | (0.8) | ​
Prior service credit, net of taxes | ​ | ​ | — | ​ | ​ | 0.1 | ​
Total | ​ | $ | (0.7) | ​ | $ | (0.7) | ​
Schedule of estimated benefit payments |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​ | ​ |  | ​ | ​ |
​ | ​ | ​ | ​ | Non-qualified | ​ | ​ |
​ | ​ | Pension | ​ | Pension | ​ | Post-retirement | ​
Year (in millions) | ​ | Benefits | ​ | Benefits | ​ | Benefits (1) |
2022 | ​ | $ | 14.5 | ​ | $ | 1.8 | ​ | $ | 0.9 | ​
2023 | ​ |  | 14.7 | ​ |  | 2.2 | ​ |  | 1.1 | ​
2024 | ​ |  | 14.8 | ​ |  | — | ​ |  | 1.0 | ​
2025 | ​ |  | 15.0 | ​ |  | 0.1 | ​ |  | 1.1 | ​
2026 | ​ |  | 15.3 | ​ |  | 0.1 | ​ |  | 1.1 | ​
2027-2031 | ​ | ​ | 76.9 | ​ | ​ | 1.3 | ​ | ​ | 5.8 | ​
Total | ​ | $ | 151.2 | ​ | $ | 5.5 | ​ | $ | 11.0 | ​
(1) | Net of participant contributions and Medicare Part D subsidies.
Schedule of information regarding the entity's participation in the multi-employer pension plans | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | Pension | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ |
​ | ​ | ​ | ​ | ​ | ​ | Protection Act | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | Zone as of | ​ | FIP/RP Status | ​ | 5% | ​ | Contributions of Matson | ​ | ​ | ​ | ​ |
​ | ​ | EIN/Pension | ​ | ​ | ​ | December 31, | ​ | Pending/ | ​ | Contributor | ​ | (in millions) | ​ | Surcharge | ​ | Expiration |
Pension Funds |  | Plan Number |  | Notes |  | 2021 |  | 2020 |  | Implemented |  | in 2021 |  | 2021 |  | 2020 |  | 2019 |  | Imposed |  | Date (2) |
American Radio Association Pension Fund |  | 13-6161999-001 | ​ |  | ​ | Green |  | Green |  | Implemented | ​ | Yes | ​ | $ | 1.1 | ​ | $ | 1.0 | ​ | $ | 1.1 |  | No |  | 6/15/2028 | ​
Hawaii Longshore Pension Plan | ​ | 99-0314293-001 | ​ | (1) | ​ | Green | ​ | N/A | ​ | Implemented | ​ | Yes | ​ | ​ | 11.1 | ​ | ​ | — | ​ | ​ | — | ​ | No | ​ | 6/30/2022 | ​
Hawaii Terminals Multiemployer Pension Plan |  | 20-0389370-001 | ​ | (1) | ​ | N/A |  | Yellow |  | N/A | ​ | N/A | ​ | ​ | — | ​ | ​ | 5.8 | ​ | ​ | 5.7 |  | N/A |  | N/A | ​
Hawaii Stevedoring Multiemployer Retirement Plan |  | 99-0314293-001 | ​ | (1) | ​ | N/A |  | Green |  | N/A | ​ | N/A | ​ |  | — | ​ |  | 4.6 | ​ |  | 4.4 |  | N/A |  | N/A | ​
Master, Mates and Pilots Pension Plan |  | 13-6372630-001 | ​ | ​ | ​ | Green |  | Green |  | No | ​ | Yes | ​ |  | 3.5 | ​ |  | 3.2 | ​ |  | 3.4 |  | No | ​ | 6/15/2027, | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/15/2028 | ​
Masters, Mates and Pilots Adjustable Pension Plan |  | 37-1719247-001 | ​ | ​ | ​ | Green |  | Green |  | No | ​ | Yes | ​ |  | 2.0 | ​ |  | 1.8 | ​ |  | 1.9 |  | No | ​ | 6/15/2027, | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/15/2028 | ​
MEBA Pension Trust - Defined Benefit Plan |  | 51-6029896-001 | ​ | ​ | ​ | Green |  | Green |  | No | ​ | Yes | ​ |  | 4.3 | ​ |  | 4.1 | ​ |  | 4.3 |  | No |  | 6/15/2022, | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/15/2028 | ​
OCU Pension Trust Plan |  | 26-1574440-001 | ​ | ​ | ​ | Green |  | Green |  | No | ​ | No | ​ |  | 0.3 | ​ |  | 0.2 | ​ |  | 0.2 |  | No |  | 6/30/2023 | ​
MFOW Supplementary Pension Plan | ​ | 94-6201677-001 | ​ | ​ | ​ | Yellow | ​ | Yellow | ​ | No | ​ | Yes | ​ | ​ | 0.1 | ​ | ​ | 0.1 | ​ | ​ | 0.1 | ​ | No | ​ | 6/30/2026 | ​
SIU Pacific District Pension Plan | ​ | 94-6061923-001 | ​ | ​ | ​ | Green | ​ | Green | ​ | No | ​ | Yes | ​ | ​ | 1.4 | ​ | ​ | 1.3 | ​ | ​ | 1.5 | ​ | No | ​ | 6/30/2026 | ​
Alaska Teamster - Employer Pension Plan | ​ | 92-6003463-024 | ​ | ​ | ​ | Red | ​ | Red | ​ | Implemented | ​ | Yes | ​ | ​ | 3.6 | ​ | ​ | 3.3 | ​ | ​ | 1.9 | ​ | Yes | ​ | 6/30/2022, | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/30/2023, | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/30/2024 | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | 6/30/2025 | ​
All Alaska Longshore Pension Plan | ​ | 91-6085352-001 | ​ | ​ | ​ | Green | ​ | Green | ​ | No | ​ | Yes | ​ | ​ | 1.6 | ​ | ​ | 1.3 | ​ | ​ | 1.2 | ​ | No | ​ | 6/30/2022 | ​
Western Conference of Teamsters Pension Plan | ​ | 91-6145047-001 | ​ | ​ | ​ | Green | ​ | Green | ​ | No | ​ | No | ​ | ​ | 1.9 | ​ | ​ | 1.6 | ​ | ​ | 1.5 | ​ | No | ​ | 3/31/2023 | ​
Western Conference of Teamsters Supplemental Benefit Trust | ​ | 95-3746907-001 | ​ | ​ | ​ | Green | ​ | Green | ​ | No | ​ | No | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | No | ​ | 3/31/2023 | ​
OPEIU Local 153 Pension Plan | ​ | 13-2864289-001 | ​ | ​ | ​ | Red | ​ | Red | ​ | Implemented | ​ | No | ​ | ​ | 0.1 | ​ | ​ | 0.1 | ​ | ​ | 0.1 | ​ | No | ​ | 11/9/2023 | ​
Seafarers Pension Plan | ​ | 13-6100329-001 | ​ | (3) | ​ | Green | ​ | Green | ​ | No | ​ | No | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | No | ​ | 6/30/2022 | ​
Total | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | $ | 31.0 | ​ | $ | 28.4 | ​ | $ | 27.3 | ​ | ​ | ​ | ​ | ​
(1) | The Hawaii Terminals Multiemployer Pension Plan merged into the Hawaii Stevedoring Multiemployer Retirement Plan effective January 1, 2021 and is formally known as the Hawaii Longshore Pension Plan.
(2) | Represents the expiration date of the collective bargaining agreement.
(3) | The Company does not make contributions directly to the Seafarers Pension Plan. Instead, contributions are made to the Seafarers Health and Benefits Plan, and are subsequently re-allocated to the Seafarers Pension Plan at the discretion of the plan Trustee.
​

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- Definition Tabular disclosure of the major categories of plan assets as a percentage of pension plans and/or other employee benefit plans. The information includes the target allocation of plan assets. + References No definition available. + Details
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- Definition Tabular disclosure of the amounts related to pension plans and/or other employee benefit plans that are recognized in the balance sheet, showing separately the assets and current and noncurrent liabilities (if applicable) recognized and that are in accumulated other comprehensive income or loss that have not yet been recognized as components of net periodic benefit cost, such as the net gain (loss), net prior service cost or credit, and net transition asset or obligation. + References No definition available. + Details
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- Definition Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) and Accumulated other comprehensive income loss for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) and the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period for pension plans and/or other employee benefit plans, and reclassification adjustments of other comprehensive income (loss) for the period, as those amounts, including amortization of the net transition asset or obligation, are recognized as components of net periodic benefit cost recognized. + References No definition available. + Details
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- Definition Tabular disclosure for pension plans and/or other employee benefit plans of the components of net benefit costs including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments, and the tabular disclosure of the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period, and reclassification adjustments of other comprehensive income (loss) for the period. + References No definition available. + Details
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- Definition Tabular disclosure of benefit obligation and plan assets of defined benefit plan with accumulated benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(5) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of information about multiemployer plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition Tabular disclosure of net funded status of pension plans and/or other employee benefit plans. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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