FAIR VALUE MEASUREMENTS AND INVESTMENTS - Recurring (Details) - Recurring basis - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair value measurements
Total assets and liabilities measured at fair value	$ (16,543)	$ (23,311)
Short Term Investments
Fair value measurements
Investments	300	300
Other investments
Fair value measurements
Investments	931	1,197
Employee benefit plan investments
Fair value measurements
Investments	3,007	3,014
Interest rate swap
Fair value measurements
Derivative liabilities	(28)	(1,750)
Redeemable common units \| Alloy Inc
Fair value measurements
Financial instruments	(14,760)	(14,760)
Redeemable common units \| Alaska communications
Fair value measurements
Financial instruments	(5,744)	(11,063)
Warrants \| Alaska communications
Fair value measurements
Financial instruments	(249)	(249)
Level 1
Fair value measurements
Total assets and liabilities measured at fair value	3,307	3,314
Level 1 \| Short Term Investments
Fair value measurements
Investments	300	300
Level 1 \| Employee benefit plan investments
Fair value measurements
Investments	3,007	3,014
Level 2
Fair value measurements
Total assets and liabilities measured at fair value	(28)	(1,750)
Level 2 \| Interest rate swap
Fair value measurements
Derivative liabilities	(28)	(1,750)
Level 3
Fair value measurements
Total assets and liabilities measured at fair value	(19,822)	(24,875)
Level 3 \| Other investments
Fair value measurements
Investments	931	1,197
Level 3 \| Redeemable common units \| Alloy Inc
Fair value measurements
Financial instruments	(14,760)	(14,760)
Level 3 \| Redeemable common units \| Alaska communications
Fair value measurements
Financial instruments	(5,744)	(11,063)
Level 3 \| Warrants \| Alaska communications
Fair value measurements
Financial instruments	$ (249)	$ (249)

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