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FAIR VALUE MEASUREMENTS AND INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Jun. 30, 2025	Dec. 31, 2024
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	$ 34,046	$ 36,646	$ 41,956	$ 41,956
Other assets and assets held for sale
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investments	25,400
India solar investment \| Held-for-sale
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Investment - Held for sale	8,600
Redeemable Common Units \| Alloy Inc
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Historical cost of redeemable units	22,300
Historical cost exceeding fair value		10,100
Fair value of units		15,000
Redeemable Common Units \| Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Fair value of units	0	0
Carrying Value
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Long-term debt	513,300	565,200
Customer receivable credit facility	35,200	39,600
Level 2 \| Total
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Long-term debt	520,300	572,300
Customer receivable credit facility	$ 34,800	$ 39,200