SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fair value Instruments - Recurring (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
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)

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. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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