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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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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) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 segment	Mar. 31, 2014 segment	Dec. 31, 2014
SEGMENT REPORTING
Number of reportable segments	5us-gaap_NumberOfReportableSegments	4us-gaap_NumberOfReportableSegments
Revenue
Revenue	$ 85,338us-gaap_Revenues	$ 75,174us-gaap_Revenues
Depreciation and amortization	14,751	11,980
Non-cash stock-based compensation	1,224us-gaap_ShareBasedCompensation	1,058us-gaap_ShareBasedCompensation
Operating income (loss)	19,151us-gaap_OperatingIncomeLoss	16,248us-gaap_OperatingIncomeLoss
Segment Assets
Net fixed assets	363,387us-gaap_PropertyPlantAndEquipmentNet		369,582us-gaap_PropertyPlantAndEquipmentNet
Goodwill	45,077us-gaap_Goodwill		45,077us-gaap_Goodwill
Total assets	924,783us-gaap_Assets		925,030us-gaap_Assets
Capital Expenditures
Capital expenditures	13,812	8,736
U.S. Wireless
Revenue
Revenue	35,843	28,392
International wireless
Revenue
Revenue	21,172	23,148
Wireline
Revenue
Revenue	20,593	21,530
Equipment and other
Revenue
Revenue	2,441	2,104
Renewable energy
Revenue
Revenue	5,289
Reconciling Items
Revenue
Revenue		(636)
Depreciation and amortization	1,133	616
Non-cash stock-based compensation	1,043	1,058
Operating income (loss)	(6,455)	(5,328)
Segment Assets
Net fixed assets	14,254		14,655
Total assets	293,148		287,871
Capital Expenditures
Capital expenditures	732	427
Reconciling Items \| Discontinued operations
Segment Assets
Total assets	44		175
Reconciling Items \| Wireline
Revenue
Revenue		(636)
U.S. Wireless \| Operating segments
Revenue
Revenue	36,479	28,723
Depreciation and amortization	4,147	3,303
Operating income (loss)	17,910	13,589
Segment Assets
Net fixed assets	80,932		79,910
Goodwill	32,148		32,148
Total assets	192,822		188,377
Capital Expenditures
Capital expenditures	6,373	5,337
U.S. Wireless \| Operating segments \| U.S. Wireless
Revenue
Revenue	35,843	28,392
U.S. Wireless \| Operating segments \| Wireline
Revenue
Revenue	152	152
U.S. Wireless \| Operating segments \| Equipment and other
Revenue
Revenue	484	179
International Integrated Telephony \| Operating segments
Revenue
Revenue	21,108	21,797
Depreciation and amortization	4,366	4,313
Operating income (loss)	3,766	5,635
Segment Assets
Net fixed assets	107,636		108,972
Total assets	196,682		201,649
Capital Expenditures
Capital expenditures	2,791	2,176
International Integrated Telephony \| Operating segments \| International wireless
Revenue
Revenue	6,126	6,897
International Integrated Telephony \| Operating segments \| Wireline
Revenue
Revenue	14,600	14,706
International Integrated Telephony \| Operating segments \| Equipment and other
Revenue
Revenue	382	194
Island Wireless \| Operating segments
Revenue
Revenue	16,565	17,923
Depreciation and amortization	2,545	2,608
Operating income (loss)	2,413	3,426
Segment Assets
Net fixed assets	23,094		26,590
Goodwill	5,438		5,438
Total assets	70,281		74,563
Capital Expenditures
Capital expenditures	2,418	366
Island Wireless \| Operating segments \| International wireless
Revenue
Revenue	15,046	16,251
Island Wireless \| Operating segments \| Equipment and other
Revenue
Revenue	1,519	1,672
U.S. Wireline \| Operating segments
Revenue
Revenue	5,897	7,367
Depreciation and amortization	1,356	1,140
Operating income (loss)	(1,135)	(1,074)
Segment Assets
Net fixed assets	27,333		28,113
Goodwill	7,491		7,491
Total assets	45,265		42,446
Capital Expenditures
Capital expenditures	1,498	430
U.S. Wireline \| Operating segments \| Wireline
Revenue
Revenue	5,841	7,308
U.S. Wireline \| Operating segments \| Equipment and other
Revenue
Revenue	56	59
Renewable energy \| Operating segments
Revenue
Revenue	5,289
Depreciation and amortization	1,204
Non-cash stock-based compensation	181
Operating income (loss)	2,652
Segment Assets
Net fixed assets	110,138		111,342
Total assets	126,585		130,124
Renewable energy \| Operating segments \| Renewable energy
Revenue
Revenue	$ 5,289