FAIR VALUE MEASUREMENTS AND INVESTMENTS - Recurring (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair value measurements
Total assets and liabilities measured at fair value	$ (9,935)	$ (23,311)
Short Term Investments
Fair value measurements
Investments	310	300
Other Investments
Fair value measurements
Investments		1,197
Employee benefit plan investments
Fair value measurements
Investments	2,800	3,014
Interest Rate Swaps
Fair value measurements
Derivative liabilities	(1,962)	(1,750)
Redeemable common units \| Alloy Inc
Fair value measurements
Financial instruments	(10,834)	(14,760)
Redeemable common units \| Alaska communications
Fair value measurements
Financial instruments		(11,063)
Warrant \| Alaska communications
Fair value measurements
Financial instruments	(249)	(249)
Level 1
Fair value measurements
Total assets and liabilities measured at fair value	3,110	3,314
Level 1 \| Short Term Investments
Fair value measurements
Investments	310	300
Level 1 \| Employee benefit plan investments
Fair value measurements
Investments	2,800	3,014
Level 2
Fair value measurements
Total assets and liabilities measured at fair value	(1,962)	(1,750)
Level 2 \| Interest Rate Swaps
Fair value measurements
Derivative liabilities	(1,962)	(1,750)
Level 3
Fair value measurements
Total assets and liabilities measured at fair value	(11,083)	(24,875)
Level 3 \| Other Investments
Fair value measurements
Investments		1,197
Level 3 \| Redeemable common units \| Alloy Inc
Fair value measurements
Financial instruments	(10,834)	(14,760)
Level 3 \| Redeemable common units \| Alaska communications
Fair value measurements
Financial instruments		(11,063)
Level 3 \| Warrant \| Alaska communications
Fair value measurements
Financial instruments	$ (249)	$ (249)

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