ACQUISITIONS AND DISPOSITIONS - Acquisition of Alaska Communications (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jul. 22, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Cash and restricted cash acquired		$ 11,900
Redeemable noncontrolling interests		72,936	$ 0
Unpaid preferred dividend		2,672	2,703	$ 2,721
Amount drawn from revolving credit facility		37,321
Revenue		602,707	455,444	438,722
Income (Loss) from Continuing Operations before Income Taxes		(22,687)	93	6,072
Transaction-related charges		$ 10,221	1,641	$ 244
Minimum
Business Acquisition [Line Items]
Useful life		3 years
Maximum
Business Acquisition [Line Items]
Useful life		39 years
Customer relationships | Minimum
Business Acquisition [Line Items]
Intangible assets useful lives		5 years
Customer relationships | Maximum
Business Acquisition [Line Items]
Intangible assets useful lives		13 years
Trade name licenses | Minimum
Business Acquisition [Line Items]
Intangible assets useful lives		6 years
Trade name licenses | Maximum
Business Acquisition [Line Items]
Intangible assets useful lives		15 years
Redeemable Common Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests		$ 22,640	0
Fair value of common units		22,600
Redeemable Preferred Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests		$ 50,296	0
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%	3.00%
Unpaid preferred dividend		$ 2,000
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		110,500
Income (Loss) from Continuing Operations before Income Taxes		(4,700)
Transaction-related charges	10,500	9,600	$ 900
Alaska communications | Warrant for redeemable common unit
Business Acquisition [Line Items]
Warrants value		600
Alaska communications | Customer relationships
Business Acquisition [Line Items]
Intangible assets	34,900
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]
Useful life	2 years
Alaska communications | Telecommunication Equipment | Maximum
Business Acquisition [Line Items]
Useful life	30 years
Alaska communications | Valuation income and cost approach | Telecommunication Equipment | Minimum
Business Acquisition [Line Items]
Discounted rate used for cash flows (as a percent)	4.00%
Alaska communications | Valuation income and cost approach | Telecommunication Equipment | Maximum
Business Acquisition [Line Items]
Discounted rate used for cash flows (as a percent)	14.00%
Alaska communications | Redeemable Common Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests	$ 22,600	22,600
Fair value of common units		22,600
Alaska communications | Redeemable Preferred Units
Business Acquisition [Line Items]
Redeemable noncontrolling interests	$ 48,300	$ 48,300
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
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