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RETIREMENT PLANS - Benefit Obligations and Plan Assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pension benefits |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | $ 64,149 | $ 66,175 |
Service cost | 80 | 90 | $ 151
Interest cost | 3,190 | 3,323 | 2,373
Benefits and settlements paid | (4,896) | (6,899) |
Actuarial (gain) loss | (2,157) | 1,460 |
Balance at end of year | 60,366 | 64,149 | 66,175
Plan net assets: |  |  |
Balance at beginning of year | 71,504 | 71,552 |
Actual return on plan assets | 2,870 | 7,142 |
Company contributions | 391 | 207 |
Benefits and settlements paid | (4,896) | (7,397) |
Balance at end of year | 69,869 | 71,504 | 71,552
Funded status of plan |  |  |
Projected benefit obligation | 60,366 | 64,149 | 66,175
Plan Net Assets | 69,869 | 71,504 | 71,552
Over/ (Under) funded status of plan | 9,503 | 7,355 |
Pension benefits | Viya Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 53,075 |  |
Balance at end of year | 49,889 | 53,075 |
Plan net assets: |  |  |
Balance at beginning of year | 62,142 |  |
Balance at end of year | 60,250 | 62,142 |
Funded status of plan |  |  |
Projected benefit obligation | 49,889 | 53,075 |
Plan Net Assets | 60,250 | 62,142 |
Over/ (Under) funded status of plan | 10,361 | 9,067 |
Pension benefits | Alaska Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 11,074 |  |
Balance at end of year | 10,477 | 11,074 |
Plan net assets: |  |  |
Balance at beginning of year | 9,362 |  |
Balance at end of year | 9,619 | 9,362 |
Funded status of plan |  |  |
Projected benefit obligation | 10,477 | 11,074 |
Plan Net Assets | 9,619 | 9,362 |
Over/ (Under) funded status of plan | (858) | (1,712) |
Postretirement benefits |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 3,625 | 3,624 |
Service cost | 76 | 65 | 124
Interest cost | 195 | 182 | 139
Benefits and settlements paid | (426) | (309) |
Actuarial (gain) loss | 61 | 63 |
Balance at end of year | 3,531 | 3,625 | 3,624
Plan net assets: |  |  |
Company contributions | 426 | 309 |
Benefits and settlements paid | (426) | (309) |
Funded status of plan |  |  |
Projected benefit obligation | 3,531 | 3,625 | $ 3,624
Over/ (Under) funded status of plan | (3,531) | (3,625) |
Postretirement benefits | Viya Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 3,341 |  |
Balance at end of year | 3,262 | 3,341 |
Funded status of plan |  |  |
Projected benefit obligation | 3,262 | 3,341 |
Over/ (Under) funded status of plan | (3,262) | (3,341) |
Postretirement benefits | Alaska Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 284 |  |
Balance at end of year | 269 | 284 |
Funded status of plan |  |  |
Projected benefit obligation | 269 | 284 |
Over/ (Under) funded status of plan | $ (269) | $ (284) |

X
- Definition Represents the amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes the amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. + References No definition available. + Details
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- Definition Represents the amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes the amount that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. + References No definition available. + Details
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- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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