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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No definition available.

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Amount of cost reimbursement funded.

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Duration of additional period requested for government assistance.

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Represents the amount of grant funds awarded.

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Amount of grant funds awarded annually.

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Amount expected to be received under the terms of governmental, corporate, or foundation grants, annually.

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- Definition

Cash inflow from government grants.

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No definition available.

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Amount of cost reimbursement allocated.

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No definition available.

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- Definition

The reimbursement period for incurred costs under a program.

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No definition available.

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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, after accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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GOVERNMENT SUPPORT AND SPECTRUM MATTERS - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Jul. 31, 2022
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount that has been funded or will be funded			$ 37,464		$ 45,144
Government capital programs - Amounts received			13,299	$ 17,281
Additional period request for government assistance	1 year
Grant funds awarded during the period			2,041
Amounts accrued for reimbursable capital expenditures from government capital programs			17,890	$ 22,191
Assets held for sale			8,600		11,200
Fixed assets, net			954,823		991,767
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
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
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
High cost support program \| Communication services \| International Telecom
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Government capital programs - Amounts received					$ 5,500
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			14,500
Reimbursable capital expenditures not probable to be received			$ 9,000
Reimbursement period			12 months
Assets held for sale			$ 7,000
Fixed assets, net			$ 2,000
Replace and Remove Program \| Maximum
GOVERNMENT SUPPORT AND SPECTRUM PROGRAMS
Amount of cost reimbursement allocated						$ 207,000