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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		6 Months Ended
SEGMENT REPORTING (Details) $ in Thousands	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($) segment	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($) segment	Dec. 31, 2015 USD ($)
Segment reporting
Number of reportable segments \| segment		5		5
Revenue
Revenue	$ 99,991	$ 90,326	$ 189,676	$ 175,670
Depreciation and amortization	16,493	14,472	31,047	29,223
Non-cash stock-based compensation	1,905	1,453	3,633	2,677
Operating income (loss)	1,912	28,732	17,804	47,892
Segment Assets
Net fixed assets	486,729		486,729		$ 373,503
Goodwill	40,865		40,865		45,077
Total assets	1,045,384		1,045,384		945,004
Capital Expenditures
Capital expenditures			42,727	28,031
U.S. Wireless
Revenue
Revenue	57,088	60,326	115,965	117,341
Wireline
Revenue
Revenue	33,976	22,089	56,421	42,681
Equipment and other
Revenue
Revenue	3,365	2,621	6,139	5,069
Renewable energy
Revenue
Revenue	5,562	5,290	11,151	10,579
Reconciling Items
Revenue
Depreciation and amortization	1,467	1,212	2,818	2,346
Non-cash stock-based compensation	1,877	1,424	3,576	2,467
Operating income (loss)	(1,221)	(7,413)	(9,875)	(13,867)
Segment Assets
Net fixed assets	10,544		10,544		14,085
Total assets	268,738		268,738		315,739
Capital Expenditures
Capital expenditures			3,755	1,679
U.S. Telecom
Revenue
Revenue	43,947	47,480	90,145	89,857
Depreciation and amortization	5,609	5,657	11,229	11,159
Operating income (loss)	4,797	23,122	21,579	39,896
Segment Assets
Net fixed assets	120,103		120,103		119,596
Goodwill	32,148		32,148		39,639
Total assets	242,524		242,524		227,707
Capital Expenditures
Capital expenditures			16,447	17,075
U.S. Telecom \| U.S. Wireless
Revenue
Revenue	37,655	40,103	77,119	75,946
U.S. Telecom \| Wireline
Revenue
Revenue	5,811	6,679	11,857	12,672
U.S. Telecom \| Equipment and other
Revenue
Revenue	481	698	1,169	1,239
International Telecom
Revenue
Revenue	50,362	37,556	88,260	75,234
Depreciation and amortization	8,209	6,399	14,586	13,310
Operating income (loss)	1,955	10,332	9,655	16,520
Segment Assets
Net fixed assets	243,935		243,935		133,262
Goodwill	5,438		5,438		5,438
Total assets	390,932		390,932		278,770
Capital Expenditures
Capital expenditures			22,283	9,265
International Telecom \| U.S. Wireless
Revenue
Revenue	19,433	20,223	38,846	41,395
International Telecom \| Wireline
Revenue
Revenue	28,165	15,410	44,564	30,009
International Telecom \| Equipment and other
Revenue
Revenue	2,764	1,923	4,850	3,830
Renewable energy
Revenue
Revenue	5,682	5,290	11,271	10,579
Depreciation and amortization	1,207	1,204	2,415	2,408
Non-cash stock-based compensation	28	29	57	210
Operating income (loss)	(3,619)	2,691	(3,555)	5,343
Segment Assets
Net fixed assets	112,147		112,147		106,560
Goodwill	3,279		3,279
Total assets	143,190		143,190		$ 122,788
Capital Expenditures
Capital expenditures			242	12
Renewable energy \| Equipment and other
Revenue
Revenue	120		120
Renewable energy \| Renewable energy
Revenue
Revenue	$ 5,562	$ 5,290	$ 11,151	$ 10,579