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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		9 Months Ended
SEGMENT REPORTING (Details) $ in Thousands	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment reporting
Number of reportable segments \| segment	5		5
Revenue
Revenue	$ 138,795	$ 96,782	$ 328,471	$ 272,453
Depreciation and amortization	21,866	14,590	52,913	43,813
Non-cash stock-based compensation	1,399	1,156	5,032	3,832
Operating income (loss)	22,081	22,524	39,886	70,411
Segment Assets
Net fixed assets	618,535		618,535		$ 373,503
Goodwill	62,042		62,042		45,077
Total assets	1,166,057		1,166,057		945,004
Capital Expenditures
Capital expenditures			78,455	46,031
U.S. Wireless
Revenue
Revenue	61,151	67,521	177,300	185,272
Wireline
Revenue
Revenue	66,129	21,760	122,190	63,520
Equipment and other
Revenue
Revenue	5,731	2,449	12,046	8,030
Renewable energy
Revenue
Revenue	5,784	5,052	16,935	15,631
Reconciling Items
Revenue
Depreciation and amortization	1,567	1,270	4,384	3,616
Non-cash stock-based compensation	1,371	1,127	4,946	3,594
Operating income (loss)	(10,219)	(9,316)	(27,398)	(23,187)
Segment Assets
Net fixed assets	10,229		10,229		14,085
Total assets	144,925		144,925		315,739
Capital Expenditures
Capital expenditures			4,877	2,576
U.S. Telecom
Revenue
Revenue	47,560	53,825	137,703	143,682
Depreciation and amortization	6,176	5,715	17,405	16,874
Operating income (loss)	18,120	24,218	39,698	64,114
Segment Assets
Net fixed assets	134,219		134,219		119,596
Goodwill	32,739		32,739		39,639
Total assets	252,827		252,827		227,707
Capital Expenditures
Capital expenditures			26,709	27,632
U.S. Telecom \| U.S. Wireless
Revenue
Revenue	40,076	47,047	117,194	122,993
U.S. Telecom \| Wireline
Revenue
Revenue	6,936	6,243	18,793	18,915
U.S. Telecom \| Equipment and other
Revenue
Revenue	548	535	1,716	1,774
International Telecom
Revenue
Revenue	85,313	37,905	173,574	113,140
Depreciation and amortization	12,896	6,400	27,482	19,710
Operating income (loss)	11,358	4,928	28,320	21,447
Segment Assets
Net fixed assets	357,733		357,733		133,262
Goodwill	26,024		26,024		5,438
Total assets	588,190		588,190		278,770
Capital Expenditures
Capital expenditures			36,543	15,797
International Telecom \| U.S. Wireless
Revenue
Revenue	21,075	20,474	60,106	62,279
International Telecom \| Wireline
Revenue
Revenue	59,193	15,517	103,397	44,605
International Telecom \| Equipment and other
Revenue
Revenue	5,045	1,914	10,071	6,256
Renewable energy
Revenue
Revenue	5,922	5,052	17,194	15,631
Depreciation and amortization	1,227	1,205	3,642	3,613
Non-cash stock-based compensation	28	29	86	238
Operating income (loss)	2,822	2,694	(734)	8,037
Segment Assets
Net fixed assets	116,354		116,354		106,560
Goodwill	3,279		3,279
Total assets	180,115		180,115		$ 122,788
Capital Expenditures
Capital expenditures			10,326	26
Renewable energy \| Equipment and other
Revenue
Revenue	138		259
Renewable energy \| Renewable energy
Revenue
Revenue	$ 5,784	$ 5,052	$ 16,935	$ 15,631