SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fair value Instruments - Recurring (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Redeemable common units
Fair value measurements
Investment, Type [Extensible Enumeration]	Alaska communications	Alaska communications
Warrant
Fair value measurements
Investment, Type [Extensible Enumeration]	Alaska communications	Alaska communications
Recurring basis
Fair value measurements
Total assets and liabilities measured at fair value	$ (21,561)	$ (36,055)
Recurring basis \| Short Term Investments
Fair value measurements
Investments	300	300
Recurring basis \| Other investments
Fair value measurements
Investments	1,197	1,616
Recurring basis \| Employee Benefit Investments
Fair value measurements
Investments	3,014
Recurring basis \| Redeemable common units
Fair value measurements
Derivative liabilities	(11,063)	(22,557)
Recurring basis \| Redeemable common units \| Alloy Inc
Fair value measurements
Derivative liabilities	(14,760)	(14,760)
Recurring basis \| Warrant
Fair value measurements
Derivative liabilities	(249)	(654)
Recurring basis \| Level 1
Fair value measurements
Total assets and liabilities measured at fair value	3,314	300
Recurring basis \| Level 1 \| Short Term Investments
Fair value measurements
Investments	300	300
Recurring basis \| Level 1 \| Employee Benefit Investments
Fair value measurements
Investments	3,014
Recurring basis \| Level 3
Fair value measurements
Total assets and liabilities measured at fair value	(24,875)	(36,355)
Recurring basis \| Level 3 \| Other investments
Fair value measurements
Investments	1,197	1,616
Recurring basis \| Level 3 \| Redeemable common units
Fair value measurements
Derivative liabilities	(11,063)	(22,557)
Recurring basis \| Level 3 \| Redeemable common units \| Alloy Inc
Fair value measurements
Derivative liabilities	(14,760)	(14,760)
Recurring basis \| Level 3 \| Warrant
Fair value measurements
Derivative liabilities	$ (249)	$ (654)

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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