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RETIREMENT PLANS - Benefit Obligations and Plan Assets (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension benefits |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | $ 66,175 | $ 100,624 |
Service cost | 90 | 151 | $ 229
Interest cost | 3,323 | 2,373 | 2,043
Benefits and settlements paid | (6,899) | (18,490) |
Actuarial (gain) loss | 1,460 | (16,758) |
Settlement |  | (1,725) |
Balance at end of year | 64,149 | 66,175 | 100,624
Plan net assets: |  |  |
Balance at beginning of year | 71,552 | 103,718 |
Actual return on plan assets | 7,142 | (13,188) |
Company contributions | 207 |  |
Benefits and settlements paid | (7,397) | (18,978) |
Balance at end of year | 71,504 | 71,552 | 103,718
Funded status of plan |  |  |
Projected benefit obligation | 64,149 | 66,175 | 100,624
Plan Net Assets | 71,504 | 71,552 | 103,718
Over/ (Under) funded status of plan | 7,355 | 5,377 |
Pension benefits | GT&T Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 2,038 |  |
Balance at end of year |  | 2,038 |
Plan net assets: |  |  |
Balance at beginning of year | 2,038 |  |
Balance at end of year |  | 2,038 |
Funded status of plan |  |  |
Projected benefit obligation |  | 2,038 |
Plan Net Assets |  | 2,038 |
Pension benefits | Viya Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 52,832 |  |
Balance at end of year | 53,075 | 52,832 |
Plan net assets: |  |  |
Balance at beginning of year | 60,132 |  |
Balance at end of year | 62,142 | 60,132 |
Funded status of plan |  |  |
Projected benefit obligation | 53,075 | 52,832 |
Plan Net Assets | 62,142 | 60,132 |
Over/ (Under) funded status of plan | 9,067 | 7,300 |
Pension benefits | Alaska Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 11,305 |  |
Balance at end of year | 11,074 | 11,305 |
Plan net assets: |  |  |
Balance at beginning of year | 9,382 |  |
Balance at end of year | 9,362 | 9,382 |
Funded status of plan |  |  |
Projected benefit obligation | 11,074 | 11,305 |
Plan Net Assets | 9,362 | 9,382 |
Over/ (Under) funded status of plan | (1,712) | (1,923) |
Postretirement benefits |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 3,624 | 5,343 |
Service cost | 65 | 124 | 143
Interest cost | 182 | 139 | 127
Benefits and settlements paid | (309) | (396) |
Actuarial (gain) loss | 63 | (1,586) |
Balance at end of year | 3,625 | 3,624 | 5,343
Plan net assets: |  |  |
Company contributions | 309 | 396 |
Benefits and settlements paid | (309) | (396) |
Funded status of plan |  |  |
Projected benefit obligation | 3,625 | 3,624 | $ 5,343
Over/ (Under) funded status of plan | (3,625) | (3,624) |
Postretirement benefits | Viya Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 3,337 |  |
Balance at end of year | 3,341 | 3,337 |
Funded status of plan |  |  |
Projected benefit obligation | 3,341 | 3,337 |
Over/ (Under) funded status of plan | (3,341) | (3,337) |
Postretirement benefits | Alaska Pension Benefit |  |  |
Projected benefit obligations: |  |  |
Balance at beginning of year | 287 |  |
Balance at end of year | 284 | 287 |
Funded status of plan |  |  |
Projected benefit obligation | 284 | 287 |
Over/ (Under) funded status of plan | $ (284) | $ (287) |

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 gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(10) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + 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)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -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 4: 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 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -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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