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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								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014 item	Dec. 31, 2013 item	Dec. 31, 2012 item
SEGMENT REPORTING
Number of reportable segments									5us-gaap_NumberOfReportableSegments	4us-gaap_NumberOfReportableSegments	4us-gaap_NumberOfReportableSegments
Revenue
Revenue	$ 88,511us-gaap_Revenues	$ 89,393us-gaap_Revenues	$ 83,269us-gaap_Revenues	$ 75,174us-gaap_Revenues	$ 77,028us-gaap_Revenues	$ 79,350us-gaap_Revenues	$ 71,625us-gaap_Revenues	$ 64,832us-gaap_Revenues	$ 336,347us-gaap_Revenues	$ 292,835us-gaap_Revenues	$ 277,796us-gaap_Revenues
Depreciation and amortization									51,234	48,737	50,587
Non-cash stock-based compensation									4,323us-gaap_ShareBasedCompensation	4,454us-gaap_ShareBasedCompensation	3,323us-gaap_ShareBasedCompensation
Operating income (loss)	19,563us-gaap_OperatingIncomeLoss	28,158us-gaap_OperatingIncomeLoss	21,607us-gaap_OperatingIncomeLoss	16,248us-gaap_OperatingIncomeLoss	16,063us-gaap_OperatingIncomeLoss	20,038us-gaap_OperatingIncomeLoss	15,906us-gaap_OperatingIncomeLoss	12,078us-gaap_OperatingIncomeLoss	85,576us-gaap_OperatingIncomeLoss	64,085us-gaap_OperatingIncomeLoss	56,638us-gaap_OperatingIncomeLoss
Segment Assets
Net fixed assets	369,582us-gaap_PropertyPlantAndEquipmentNet				254,632us-gaap_PropertyPlantAndEquipmentNet				369,582us-gaap_PropertyPlantAndEquipmentNet	254,632us-gaap_PropertyPlantAndEquipmentNet
Goodwill	45,077us-gaap_Goodwill				45,077us-gaap_Goodwill				45,077us-gaap_Goodwill	45,077us-gaap_Goodwill
Total assets	925,030us-gaap_Assets				859,719us-gaap_Assets				925,030us-gaap_Assets	859,719us-gaap_Assets
Capital Expenditures
Capital expenditures									58,300	69,316	42,154
U.S. Wireless
Revenue
Revenue									153,040	107,930	102,817
International wireless
Revenue
Revenue									88,650	91,432	81,463
Wireline
Revenue
Revenue									85,284	84,585	85,524
Equipment and other
Revenue
Revenue									9,373	8,888	7,992
Reconciling Items
Revenue
Depreciation and amortization									3,980	2,967	2,625
Non-cash stock-based compensation									4,323	3,805	3,323
Operating income (loss)									(26,399)	(25,978)	(21,040)
Segment Assets
Net fixed assets	14,655				6,731				14,655	6,731
Total assets	288,162				395,692				288,162	395,692
Capital Expenditures
Capital expenditures									3,464	3,881	2,956
Reconciling Items \| Discontinued operations
Segment Assets
Total assets	175				4,748				175	4,748
U.S. Wireless \| Operating segments
Revenue
Revenue									154,592	109,005	103,768
Depreciation and amortization									14,345	14,308	16,072
Operating income (loss)									89,187	54,867	60,290
Segment Assets
Net fixed assets	79,910				73,592				79,910	73,592
Goodwill	32,148				32,148				32,148	32,148
Total assets	188,377				146,346				188,377	146,346
Capital Expenditures
Capital expenditures									33,446	34,895	9,792
U.S. Wireless \| Operating segments \| U.S. Wireless
Revenue
Revenue									153,040	107,930	102,817
U.S. Wireless \| Operating segments \| Wireline
Revenue
Revenue									609	610	603
U.S. Wireless \| Operating segments \| Equipment and other
Revenue
Revenue									943	465	348
International Integrated Telephony \| Operating segments
Revenue
Revenue									86,932	93,446	94,135
Depreciation and amortization									17,408	17,975	17,963
Operating income (loss)									19,628	28,212	23,203
Segment Assets
Net fixed assets	108,972				118,917				108,972	118,917
Total assets	201,335				197,903				201,335	197,903
Capital Expenditures
Capital expenditures									10,646	12,452	14,369
International Integrated Telephony \| Operating segments \| International wireless
Revenue
Revenue									26,819	30,334	27,084
International Integrated Telephony \| Operating segments \| Wireline
Revenue
Revenue									59,129	61,475	65,313
International Integrated Telephony \| Operating segments \| Equipment and other
Revenue
Revenue									984	1,637	1,738
Island Wireless \| Operating segments
Revenue
Revenue									68,575	67,653	60,096
Depreciation and amortization									10,671	10,305	11,067
Operating income (loss)									9,046	8,610	(3,334)
Segment Assets
Net fixed assets	26,590				29,310				26,590	29,310
Goodwill	5,438				5,438				5,438	5,438
Total assets	74,563				74,427				74,563	74,427
Capital Expenditures
Capital expenditures									6,064	5,536	4,529
Island Wireless \| Operating segments \| International wireless
Revenue
Revenue									61,831	61,098	54,379
Island Wireless \| Operating segments \| Equipment and other
Revenue
Revenue									6,744	6,555	5,717
U.S. Wireline \| Operating segments
Revenue
Revenue									25,799	22,731	19,797
Depreciation and amortization									4,725	3,182	2,860
Operating income (loss)									(3,668)	(1,076)	(2,481)
Segment Assets
Net fixed assets	28,113				26,082				28,113	26,082
Goodwill	7,491				7,491				7,491	7,491
Total assets	42,446				45,351				42,446	45,351
Capital Expenditures
Capital expenditures									4,680	12,552	10,508
U.S. Wireline \| Operating segments \| Wireline
Revenue
Revenue									25,546	22,500	19,608
U.S. Wireline \| Operating segments \| Equipment and other
Revenue
Revenue									253	231	189
Energy \| Operating segments
Revenue
Revenue									449
Depreciation and amortization									105
Operating income (loss)									(2,218)
Segment Assets
Net fixed assets	111,342								111,342
Total assets	130,124								130,124
Energy \| Operating segments \| Equipment and other
Revenue
Revenue									$ 449