The amount accrued for reimbursable capital expenditures from government capital programs.

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The reimbursable capital expenditures from government capital programs considered as not probable to be received.

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The transfer to fixed assets of reimbursable capital expenditures from government capital programs considered as not probable to be received

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Amount of cost reimbursement funded.

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Cash inflow from government grants.

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The reimbursement period for incurred costs under a program.

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Carrying amount as of the balance sheet date of amounts due under the terms of governmental, corporate, or foundation grants.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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GOVERNMENT SUPPORT AND SPECTRUM MATTERS - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2024	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Jul. 31, 2022
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount that has been funded or will be funded		$ 38,218		$ 38,218		$ 45,144
Revenue from contract with customer		170,549	$ 166,484	338,496	$ 331,123
Government capital programs - Amounts received				22,423	41,364
Amounts accrued for reimbursable capital expenditures from government capital programs				15,113	18,279
Alaska Connect Fund \| Grant receivable from January 1, 2025 through December 2028
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Grants expected to be received per year		25,600		25,600
Universal Service Fund programs
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Grant funds awarded annually				2,500
Connect America Fund II
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Grant funds awarded annually				8,000
Enhanced Alternative Connect America Cost Model \| Grant receivable through 2029
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount that has been funded or will be funded		9,000		9,000
Enhanced Alternative Connect America Cost Model \| Grant receivable in year 2038
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount that has been funded or will be funded		13,000		13,000
High cost support program \| Communication services \| International Telecom
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Government capital programs - Amounts received						$ 5,500
Rural Digital Opportunity Fund Phase I \| Communication services
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Revenue from contract with customer		75	69	150	144
Rural Health Care ("RHC") \| Communication services
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Revenue from contract with customer		$ 6,563	$ 4,353	12,881	$ 8,715
Replace and Remove Program
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Cost reimbursement amount funded	$ 517,000
Amounts accrued for reimbursable capital expenditures from government capital programs				12,500
Reimbursable capital expenditures not probable to be received				9,000
Transferred to fixed assets				$ 9,000
Reimbursement period				12 months
Replace and Remove Program \| Maximum
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount of cost reimbursement allocated							$ 207,000