ACQUISITIONS AND DISPOSITIONS - Acquisition of Alaska Communications (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Jul. 22, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Business Acquisition [Line Items]
Redeemable noncontrolling interests		$ 74,052		$ 72,936
Amount drawn from revolving credit facility		8,000	$ 10,814
Revenue		172,019	124,510
Income (Loss) from Continuing Operations before Income Taxes		995	4,571
Transaction-related charges		554	$ 730
Redeemable Common Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests		22,640		22,640
Redeemable Preferred Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests		51,412		$ 50,296
Alaska communications
Business Acquisition [Line Items]
Price of common share	$ 3.40
Consideration Transferred	$ 353,280
Cash consideration	339,500
Cash and restricted cash acquired	$ 11,900
Percentage of additional equity interest	3.00%
Original issue price		48,300
Accrued preferred dividend		3,100
Accrued consideration	$ 1,900
Payment for purchase of Alaska Communications equity	186,800
Repayment of Alaska Communications debt	164,600
Mezzanine equity contribution received from Freedom 3 Investors	$ 71,500
Percentage of voting interest	52.00%
Deferred revenue from long term customer contracts	$ 81,500
Revenue		58,300
Income (Loss) from Continuing Operations before Income Taxes		(2,800)
Transaction-related charges	11,000	500
Alaska communications | Warrant for redeemable common unit
Business Acquisition [Line Items]
Warrants value	600	600
Alaska communications | Customer relationships
Business Acquisition [Line Items]
Intangible assets	$ 34,900
Alaska communications | Customer relationships | Minimum
Business Acquisition [Line Items]
Intangible assets useful lives	5 years
Alaska communications | Customer relationships | Maximum
Business Acquisition [Line Items]
Intangible assets useful lives	15 years
Alaska communications | Trade name licenses
Business Acquisition [Line Items]
Intangible assets	$ 9,500
Alaska communications | Trade name licenses | Minimum
Business Acquisition [Line Items]
Intangible assets useful lives	5 years
Alaska communications | Trade name licenses | Maximum
Business Acquisition [Line Items]
Intangible assets useful lives	15 years
Alaska communications | Telecommunication Equipment | Minimum
Business Acquisition [Line Items]
Discounted rate used for cash flows (as a percent)	4.00%
Useful life	2 years
Alaska communications | Telecommunication Equipment | Maximum
Business Acquisition [Line Items]
Discounted rate used for cash flows (as a percent)	14.00%
Useful life	30 years
Alaska communications | Redeemable Common Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests	$ 22,600	22,600
Fair value of units		22,600
Alaska communications | Redeemable Preferred Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests	$ 48,300	48,300
Fair value of units		$ 51,400
Percentage of preferred dividend	9.00%	9.00%
Alaska credit facility | Alaska communications
Business Acquisition [Line Items]
Principal amount	$ 283,000
Debt issuance and debt discount costs	6,600
Amount drawn from revolving credit facility	220,000
Alaska Term Loan | Alaska communications
Business Acquisition [Line Items]
Principal amount	210,000
Alaska revolving facility | Alaska communications
Business Acquisition [Line Items]
Principal amount	10,000
Amount drawn from revolving credit facility	$ 63,000