SEGMENT REPORTING (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Revenue
Revenue	$ 123,245	$ 99,991	$ 251,360	$ 189,676
Depreciation and amortization	22,254	16,493	44,747	31,047
Non-cash stock-based compensation	2,098	1,905	3,786	3,633
Operating income (loss)	15,843	1,912	33,636	17,804
Segment Assets
Cash, Cash equivalents, and Investments	239,395		239,395		$ 278,958
Total current assets	344,335		344,335		367,369
Fixed assets, net	649,734		649,734		647,712
Goodwill	62,873		62,873		62,873
Total assets	1,201,476		1,201,476		1,198,218
Total current liabilities	151,891		151,891		150,105
Total debt	159,682		159,682		156,823
Capital Expenditures
Capital expenditures			78,549	42,727
Wireless
Revenue
Revenue	54,460	57,088	110,690	115,965
Wireline
Revenue
Revenue	61,459	33,976	125,259	56,421
Renewable energy
Revenue
Revenue	4,891	5,562	9,791	11,151
Equipment and other
Revenue
Revenue	2,435	3,365	5,620	6,139
Corporate and Other
Revenue
Depreciation and amortization	1,044	1,468	2,416	2,817
Non-cash stock-based compensation	2,061	1,877	3,591	3,576
Operating income (loss)	(8,955)	(8,526)	(17,955)	(17,179)
Segment Assets
Cash, Cash equivalents, and Investments	107,679		107,679		131,664
Total current assets	121,045		121,045		135,745
Fixed assets, net	15,951		15,951		15,429
Total assets	190,733		190,733		170,505
Total current liabilities	15,128		15,128		18,838
Capital Expenditures
Capital expenditures			3,294	3,755
U.S. Telecom | Operating segments
Revenue
Revenue	36,978	43,946	80,771	90,145
Depreciation and amortization	6,246	5,609	12,797	11,229
Operating income (loss)	13,147	4,797	28,533	21,579
Segment Assets
Cash, Cash equivalents, and Investments	14,353		14,353		22,235
Total current assets	43,730		43,730		50,983
Fixed assets, net	102,532		102,532		129,274
Goodwill	35,268		35,268		35,268
Total assets	205,968		205,968		240,006
Total current liabilities	44,733		44,733		23,162
Capital Expenditures
Capital expenditures			12,602	16,447
U.S. Telecom | Operating segments | Wireless
Revenue
Revenue	34,505	37,655	71,668	77,119
U.S. Telecom | Operating segments | Wireline
Revenue
Revenue	2,057	5,811	8,108	11,857
U.S. Telecom | Operating segments | Equipment and other
Revenue
Revenue	416	480	995	1,169
International Telecom | Operating segments
Revenue
Revenue	81,370	50,363	160,660	88,260
Depreciation and amortization	13,134	8,209	26,250	14,586
Non-cash stock-based compensation	8		138
Operating income (loss)	10,805	9,259	20,771	16,959
Segment Assets
Cash, Cash equivalents, and Investments	98,684		98,684		97,681
Total current assets	152,351		152,351		143,201
Fixed assets, net	374,748		374,748		372,741
Goodwill	24,326		24,326		24,326
Total assets	602,990		602,990		597,454
Total current liabilities	76,896		76,896		95,502
Total debt	95,446		95,446		91,316
Capital Expenditures
Capital expenditures			37,118	22,283
International Telecom | Operating segments | Wireless
Revenue
Revenue	19,955	19,433	39,022	38,846
International Telecom | Operating segments | Wireline
Revenue
Revenue	59,402	28,165	117,151	44,564
International Telecom | Operating segments | Equipment and other
Revenue
Revenue	2,013	2,765	4,487	4,850
Renewable energy | Operating segments
Revenue
Revenue	4,897	5,682	9,929	11,271
Depreciation and amortization	1,830	1,207	3,284	2,415
Non-cash stock-based compensation	29	28	57	57
Operating income (loss)	846	(3,618)	2,287	(3,555)
Segment Assets
Cash, Cash equivalents, and Investments	18,679		18,679		27,378
Total current assets	27,209		27,209		37,440
Fixed assets, net	156,503		156,503		130,268
Goodwill	3,279		3,279		3,279
Total assets	201,785		201,785		190,253
Total current liabilities	15,134		15,134		12,603
Total debt	64,236		64,236		$ 65,507
Capital Expenditures
Capital expenditures			25,535	242
Renewable energy | Operating segments | Renewable energy
Revenue
Revenue	4,891	5,562	9,791	11,151
Renewable energy | Operating segments | Equipment and other
Revenue
Revenue	$ 6	$ 120	$ 138	$ 120