SEGMENT REPORTING (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Revenue
Revenue	$ 128,115	$ 89,686
Depreciation and amortization	22,494	14,554
Non-cash stock-based compensation	1,666	1,728
Operating income (loss)	17,793	15,893
Segment Assets
Cash, Cash equivalents, and Investments	274,248		$ 278,958
Total current assets	376,630		367,369
Fixed assets, net	639,223		647,712
Goodwill	62,873		62,873
Total assets	1,193,400		1,198,218
Total current liabilities	161,825		150,105
Total debt	152,399		156,823
Capital Expenditures
Capital expenditures	45,702	16,445
Wireless
Revenue
Revenue	56,230	58,878
Wireline
Revenue
Revenue	63,800	22,445
Equipment and other
Revenue
Revenue	3,185	2,774
Renewable energy
Revenue
Revenue	4,900	5,589
Reconciling Items
Revenue
Depreciation and amortization	1,372	1,352
Non-cash stock-based compensation	1,508	1,700
Operating income (loss)	(10,231)	(8,653)
Segment Assets
Cash, Cash equivalents, and Investments	142,689		131,664
Total current assets	155,802		135,745
Fixed assets, net	15,594		15,429
Total assets	190,381		170,505
Total current liabilities	21,474		18,838
Capital Expenditures
Capital expenditures	1,204	1,110
U.S. Telecom \| Operating segments
Revenue
Revenue	43,792	46,198
Depreciation and amortization	6,551	5,654
Operating income (loss)	16,617	16,746
Segment Assets
Cash, Cash equivalents, and Investments	16,143		22,235
Total current assets	46,955		50,983
Fixed assets, net	102,366		129,274
Goodwill	35,268		35,268
Total assets	209,026		240,006
Total current liabilities	38,469		23,162
Capital Expenditures
Capital expenditures	6,044	7,561
U.S. Telecom \| Operating segments \| Wireless
Revenue
Revenue	37,162	39,464
U.S. Telecom \| Operating segments \| Wireline
Revenue
Revenue	6,051	6,046
U.S. Telecom \| Operating segments \| Equipment and other
Revenue
Revenue	579	688
International Telecom \| Operating segments
Revenue
Revenue	79,291	37,899
Depreciation and amortization	13,117	6,341
Non-cash stock-based compensation	129
Operating income (loss)	9,966	7,737
Segment Assets
Cash, Cash equivalents, and Investments	97,104		97,681
Total current assets	146,696		143,201
Fixed assets, net	368,372		372,741
Goodwill	24,326		24,326
Total assets	595,135		597,454
Total current liabilities	85,774		95,502
Total debt	88,120		91,316
Capital Expenditures
Capital expenditures	16,666	7,774
International Telecom \| Operating segments \| Wireless
Revenue
Revenue	19,068	19,414
International Telecom \| Operating segments \| Wireline
Revenue
Revenue	57,749	16,399
International Telecom \| Operating segments \| Equipment and other
Revenue
Revenue	2,474	2,086
Renewable energy \| Operating segments
Revenue
Revenue	5,032	5,589
Depreciation and amortization	1,454	1,207
Non-cash stock-based compensation	29	28
Operating income (loss)	1,441	63
Segment Assets
Cash, Cash equivalents, and Investments	18,312		27,378
Total current assets	27,177		37,440
Fixed assets, net	152,891		130,268
Goodwill	3,279		3,279
Total assets	198,858		190,253
Total current liabilities	16,108		12,603
Total debt	64,279		$ 65,507
Capital Expenditures
Capital expenditures	21,788
Renewable energy \| Operating segments \| Equipment and other
Revenue
Revenue	132
Renewable energy \| Operating segments \| Renewable energy
Revenue
Revenue	$ 4,900	$ 5,589

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