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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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