SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Redeemable Noncontrolling Interests - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reconciliation from basic to diluted weighted average common shares outstanding
Redeemable units	$ 76,303	$ 85,917	$ 92,469
Warrants value	300	300
Redeemable Common Units
Reconciliation from basic to diluted weighted average common shares outstanding
Redeemable units	10,599	25,823	37,317
Allocated losses	17,700	11,000
Increase (decrease) in book value	2,500	(500)
Redeemable Preferred Units
Reconciliation from basic to diluted weighted average common shares outstanding
Redeemable units	$ 65,704	60,094	$ 55,152
Percentage of preferred dividend	9.00%
Unpaid dividend	$ 17,400	11,800
Alaska communications
Reconciliation from basic to diluted weighted average common shares outstanding
Percentage of additional equity interest	3.00%
Alaska communications \| Redeemable Common Units
Reconciliation from basic to diluted weighted average common shares outstanding
Fair value of common units	$ 0	11,100
Sacred Wind Enterprises \| Redeemable Common Units
Reconciliation from basic to diluted weighted average common shares outstanding
Redeemable units	10,600
Fair value of common units	$ 10,100	$ 14,800

Percentage of additional equity interest allowed to be purchased.

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- Definition

Amount of increase (decrease) in redeemable non controlling interest from changes in fair value.

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- Definition

Fair value portion of shares that an entity is required to redeem for cash or other assets at a fixed or determinable date or upon the occurrence of an event.

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- Definition

The amount of unpaid dividends to redeemable noncontrolling interest.

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- Definition

The percentage rate used to calculate dividend payments on redeemable preferred stock.

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- Definition

Amount of Net Income (Loss) attributable to redeemable noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(19))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

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- Definition

Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(27)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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