FAIR VALUE MEASUREMENTS AND INVESTMENTS - Recurring (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Warrants \| Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Financial instruments	$ 0	$ (200)
Recurring
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Total assets and liabilities measured at fair value	2,033	2,096
Recurring \| Short term investments
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	395	300
Recurring \| Employee benefit plan investments
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	2,048	2,768
Recurring \| Interest rate swap
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Derivative liabilities	(410)	(723)
Recurring \| Warrants \| Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Financial instruments		(249)
Recurring \| Level 1
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Total assets and liabilities measured at fair value	2,443	3,068
Recurring \| Level 1 \| Short term investments
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	395	300
Recurring \| Level 1 \| Employee benefit plan investments
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	2,048	2,768
Recurring \| Level 2
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Total assets and liabilities measured at fair value	(410)	(723)
Recurring \| Level 2 \| Interest rate swap
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Derivative liabilities	$ (410)	(723)
Recurring \| Level 3
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Total assets and liabilities measured at fair value		(249)
Recurring \| Level 3 \| Warrants \| Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Financial instruments		$ (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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