The amount of capital expenditures offset by the use of grants during the period.

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Amount before accumulated depreciation of remaining amount due of capital assets used in the normal conduct of business to produce goods and services.

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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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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

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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 of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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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, 2017	Dec. 31, 2016	Dec. 31, 2015
Fixed Assets
Total plant in service	$ 1,046,805	$ 1,036,370
Total property, plant, and equipment	1,169,806	1,138,362
Less: Accumulated depreciation	(526,660)	(490,650)
Net fixed assets	643,146	647,712
Depreciation and amortization	83,300	73,300	$ 55,900
Gain on disposition of long-lived assets	(101)	(27)	2,823
Capital expenditures offset by grants	$ 1,500	2,300	2,600
U.S. Telecom
Fixed Assets
Gain on disposition of long-lived assets			$ 2,800
Minimum
Fixed Assets
Useful Life	3 years
Maximum
Fixed Assets
Useful Life	39 years
Telecommunications equipment and towers
Fixed Assets
Total plant in service	$ 774,548	802,415
Capital leased assets, cost	30,000	13,800
Capital leased assets, net	24,400	12,400
Capital leased Assets, remaining amount due	$ 600	$ 1,200
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	$ 113,218	$ 115,932
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	$ 76,706	$ 44,147
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	$ 48,058	$ 43,609
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	$ 12,221	$ 12,043
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	$ 2,864	$ 325
Land
Fixed Assets
Total plant in service	12,516	10,242
Furniture and fixtures
Fixed Assets
Total plant in service	$ 6,674	$ 7,657
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	$ 123,001	$ 101,992