FAIR VALUE MEASUREMENTS AND INVESTMENTS - Recurring (Details) - USD ($) $ in Thousands	Jun. 30, 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	2,692	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	2,199	2,768
Recurring \| Interest rate swap
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Derivative liabilities	98	(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	2,594	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	2,199	2,768
Recurring \| Level 2
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Total assets and liabilities measured at fair value	98	(723)
Recurring \| Level 2 \| Interest rate swap
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Derivative liabilities	$ 98	(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)

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