The amount of revenue from reimbursement of capital expenditure grant.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures, but excludes construction in progress.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Amount, after accumulated amortization, of capitalized implementation cost from hosting arrangement that is service contract.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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FIXED ASSETS (Details) - USD ($) $ in Thousands	12 Months Ended
FIXED ASSETS (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fixed Assets
Total plant in service	$ 1,201,871	$ 1,190,375
Total property, plant, and equipment	1,252,780	1,237,555
Less: Accumulated depreciation	(716,318)	(631,974)
Net fixed assets	536,462	605,581
Depreciation and amortization	86,500	86,900	$ 83,000
Capital expenditure grants	16,300	3,100
Capitalized implementation costs	5,600	3,600
Amortization of implementation costs	$ 700	200
Minimum
Fixed Assets
Useful Life	3 years
Maximum
Fixed Assets
Useful Life	39 years
Telecommunications equipment and towers
Fixed Assets
Total plant in service	$ 1,012,457	979,028
Capital leased assets, cost	25,400	25,900
Capital leased assets, net	$ 15,900	$ 16,500
Telecommunications equipment and towers \| Minimum
Fixed Assets
Useful Life	5 years	5 years
Telecommunications equipment and towers \| Maximum
Fixed Assets
Useful Life	15 years	15 years
Solar assets
Fixed Assets
Total plant in service		$ 40,043
Solar assets \| Minimum
Fixed Assets
Useful Life	20 years	20 years
Solar assets \| Maximum
Fixed Assets
Useful Life	23 years	23 years
Office and computer equipment
Fixed Assets
Total plant in service	$ 87,427	$ 82,630
Office and computer equipment \| Minimum
Fixed Assets
Useful Life	3 years	3 years
Office and computer equipment \| Maximum
Fixed Assets
Useful Life	10 years	10 years
Buildings
Fixed Assets
Total plant in service	$ 52,048	$ 48,565
Buildings \| Minimum
Fixed Assets
Useful Life	15 years	15 years
Buildings \| Maximum
Fixed Assets
Useful Life	39 years	39 years
Transportation vehicles
Fixed Assets
Total plant in service	$ 13,730	$ 13,424
Transportation vehicles \| Minimum
Fixed Assets
Useful Life	3 years	3 years
Transportation vehicles \| Maximum
Fixed Assets
Useful Life	10 years	10 years
Leasehold improvements
Fixed Assets
Total plant in service	$ 16,709	$ 2,316
Land
Fixed Assets
Total plant in service	8,180	15,503
Furniture and fixtures
Fixed Assets
Total plant in service	$ 11,320	$ 8,866
Furniture and fixtures \| Minimum
Fixed Assets
Useful Life	5 years	5 years
Furniture and fixtures \| Maximum
Fixed Assets
Useful Life	10 years	10 years
Construction in progress
Fixed Assets
Total property, plant, and equipment	$ 50,909	$ 47,180