SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($) segment	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Segment reporting
Number of reportable segments | segment		4	5
Revenue
Revenue	$ 90,326	$ 83,269	$ 175,670	$ 158,443
Depreciation and amortization	14,472	12,930	29,223	24,910
Non-cash stock-based compensation	1,453	1,323	2,677	2,379
Operating income (loss)	28,732	21,607	47,892	37,855
Segment Assets
Net fixed assets	362,432		362,432		$ 369,582
Goodwill	45,077		45,077		45,077
Total assets	937,155		937,155		925,030
Capital Expenditures
Capital expenditures			28,031	25,104
U.S. Wireless
Revenue
Revenue	40,103	37,456	75,946	65,848
International wireless
Revenue
Revenue	20,223	22,422	41,395	45,570
Wireline
Revenue
Revenue	22,089	21,283	42,681	42,813
Equipment and other
Revenue
Revenue	2,621	2,108	5,069	4,212
Renewable energy
Revenue
Revenue	5,290		10,579
Reconciling Items
Revenue
Depreciation and amortization	1,212	1,284	2,346	1,899
Non-cash stock-based compensation	1,424	1,323	2,467	2,379
Operating income (loss)	(7,413)	(7,224)	(13,867)	(12,552)
Segment Assets
Net fixed assets	13,988		13,988		14,655
Total assets	303,396		303,396		287,871
Capital Expenditures
Capital expenditures			1,679	1,253
Reconciling Items | Discontinued operations
Segment Assets
Total assets	70		70		175
U.S. Wireless
Revenue
Revenue	40,897	37,815	77,377	66,538
Depreciation and amortization	4,507	3,453	8,653	6,756
Operating income (loss)	24,043	22,651	41,952	36,240
Segment Assets
Net fixed assets	83,456		83,456		79,910
Goodwill	32,148		32,148		32,148
Total assets	194,477		194,477		188,377
Capital Expenditures
Capital expenditures			14,125	14,845
U.S. Wireless | U.S. Wireless
Revenue
Revenue	40,103	37,456	75,946	65,848
U.S. Wireless | Wireline
Revenue
Revenue	152	152	305	305
U.S. Wireless | Equipment and other
Revenue
Revenue	642	207	1,126	385
International Integrated Telephony
Revenue
Revenue	22,357	21,397	43,463	43,195
Depreciation and amortization	4,413	4,400	8,780	8,713
Operating income (loss)	6,466	4,594	10,232	10,229
Segment Assets
Net fixed assets	104,828		104,828		108,972
Total assets	200,602		200,602		201,649
Capital Expenditures
Capital expenditures			4,748	6,072
International Integrated Telephony | International wireless
Revenue
Revenue	6,485	6,758	12,611	13,655
International Integrated Telephony | Wireline
Revenue
Revenue	15,410	14,445	30,009	29,151
International Integrated Telephony | Equipment and other
Revenue
Revenue	462	194	843	389
Island Wireless
Revenue
Revenue	15,199	17,305	31,771	35,228
Depreciation and amortization	1,986	2,607	4,530	5,215
Operating income (loss)	3,866	2,552	6,288	5,978
Segment Assets
Net fixed assets	23,050		23,050		26,590
Goodwill	5,438		5,438		5,438
Total assets	73,703		73,703		74,563
Capital Expenditures
Capital expenditures			4,517	1,958
Island Wireless | International wireless
Revenue
Revenue	13,738	15,664	28,784	31,915
Island Wireless | Equipment and other
Revenue
Revenue	1,461	1,641	2,987	3,313
U.S. Wireline
Revenue
Revenue	6,583	6,752	12,480	13,482
Depreciation and amortization	1,150	1,186	2,506	2,327
Operating income (loss)	(921)	(966)	(2,056)	(2,040)
Segment Assets
Net fixed assets	28,165		28,165		28,113
Goodwill	7,491		7,491		7,491
Total assets	42,895		42,895		42,446
Capital Expenditures
Capital expenditures			2,950	976
U.S. Wireline | Wireline
Revenue
Revenue	6,527	6,686	12,367	13,357
U.S. Wireline | Equipment and other
Revenue
Revenue	56	$ 66	113	$ 125
Renewable energy
Revenue
Revenue	5,290		10,579
Depreciation and amortization	1,204		2,408
Non-cash stock-based compensation	29		210
Operating income (loss)	2,691		5,343
Segment Assets
Net fixed assets	108,945		108,945		111,342
Total assets	122,080		122,080		$ 130,124
Capital Expenditures
Capital expenditures			12
Renewable energy | Renewable energy
Revenue
Revenue	$ 5,290		$ 10,579