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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fair value Instruments - Recurring (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Warrant [Member] |  |
Fair value measurements |  |
Investment, Type [Extensible Enumeration] | Alaska communications |
Recurring |  |
Fair value measurements |  |
Total assets and liabilities measured at fair value | $ 2,096 | $ (23,311)
Recurring | Short Term Investments |  |
Fair value measurements |  |
Investments | 300 | 300
Recurring | Other Investments |  |
Fair value measurements |  |
Investments |  | 1,197
Recurring | Employee benefit plan investments |  |
Fair value measurements |  |
Investments | 2,768 | 3,014
Recurring | Interest Rate Swaps |  |
Fair value measurements |  |
Investments | (723) | (1,750)
Recurring | Redeemable common units |  |
Fair value measurements |  |
Derivative liabilities |  | (11,063)
Recurring | Redeemable common units | Alloy Inc |  |
Fair value measurements |  |
Derivative liabilities |  | (14,760)
Recurring | Warrant [Member] |  |
Fair value measurements |  |
Derivative liabilities | (249) | (249)
Recurring | Level 1 |  |
Fair value measurements |  |
Total assets and liabilities measured at fair value | 3,068 | 3,314
Recurring | Level 1 | Short Term Investments |  |
Fair value measurements |  |
Investments | 300 | 300
Recurring | Level 1 | Employee benefit plan investments |  |
Fair value measurements |  |
Investments | 2,768 | 3,014
Recurring | Level 2 |  |
Fair value measurements |  |
Total assets and liabilities measured at fair value | (723) | (1,750)
Recurring | Level 2 | Interest Rate Swaps |  |
Fair value measurements |  |
Investments | (723) | (1,750)
Recurring | Level 3 |  |
Fair value measurements |  |
Total assets and liabilities measured at fair value | (249) | (24,875)
Recurring | Level 3 | Other Investments |  |
Fair value measurements |  |
Investments |  | 1,197
Recurring | Level 3 | Redeemable common units |  |
Fair value measurements |  |
Derivative liabilities |  | (11,063)
Recurring | Level 3 | Redeemable common units | Alloy Inc |  |
Fair value measurements |  |
Derivative liabilities |  | (14,760)
Recurring | Level 3 | Warrant [Member] |  |
Fair value measurements |  |
Derivative liabilities | $ (249) | $ (249)

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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. 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