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FAIR VALUE MEASUREMENTS AND INVESTMENTS - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Redeemable units	$ 84,328	$ 76,303	$ 75,083	$ 85,917
Redeemable Common Units
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Redeemable units	14,101	10,599	$ 10,835	$ 25,823
Redeemable Common Units | Alloy Inc
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Redeemable units	14,100	10,600
Redeemable Common Units | Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Fair value of units	0	0
Warrants | Alaska Communications
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Financial instruments	0	(200)
Carrying Value
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Long-term debt	579,600	557,400
Level 2 | Total
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Long-term debt	585,900	564,400
Customer receivable credit facility	37,800	42,700
Level 2 | Carrying Value
FAIR VALUE MEASUREMENTS AND INVESTMENTS
Customer receivable credit facility	$ 38,200	$ 44,200

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