SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment reporting
Number of reportable segments \| segment	3
Revenue
Revenue	$ 110,905	$ 103,300
Depreciation and amortization	22,518	20,718
Non-cash stock-based compensation	1,160	1,301
Operating income (loss)	7,299	2,114
Segment Assets
Cash, Cash equivalents, and Investments	146,017		$ 161,703
Total current assets	235,342		228,723
Fixed assets, net	592,927		605,581
Goodwill	60,691		60,691
Total assets	1,108,592		1,130,726
Total current liabilities	113,444		119,669
Total debt	85,525		86,426
Capital Expenditures
Capital expenditures	14,061	17,764
Hurricane rebuild capital expenditures		123
Communication services
Revenue
Revenue	107,896	100,465
Mobility
Revenue
Revenue	23,792	23,664
Fixed
Revenue
Revenue	61,252	57,457
Carrier services
Revenue
Revenue	22,636	19,157
Other
Revenue
Revenue	216	187
Other
Revenue
Revenue	3,009	2,835
Renewable Energy
Revenue
Revenue	1,322	1,490
Managed Services
Revenue
Revenue	1,687	1,345
Corporate and Other
Revenue
Depreciation and amortization	1,703	1,489
Non-cash stock-based compensation	1,197	1,290
Operating income (loss)	(7,915)	(8,055)
Segment Assets
Cash, Cash equivalents, and Investments	37,885		55,284
Total current assets	51,932		55,485
Fixed assets, net	20,709		21,453
Total assets	165,837		184,419
Total current liabilities	13,745		14,375
Capital Expenditures
Capital expenditures	904	2,724
International Telecom \| Operating segments
Revenue
Revenue	82,284	80,317
Depreciation and amortization	14,315	13,015
Non-cash stock-based compensation	(37)	11
Operating income (loss)	13,477	13,878
Segment Assets
Cash, Cash equivalents, and Investments	48,222		43,125
Total current assets	95,764		91,497
Fixed assets, net	462,275		466,523
Goodwill	25,421		25,421
Total assets	645,987		647,228
Total current liabilities	71,129		77,644
Total debt	85,525		86,426
Capital Expenditures
Capital expenditures	10,465	11,356
Hurricane rebuild capital expenditures		100
International Telecom \| Operating segments \| Communication services
Revenue
Revenue	80,605	79,107
International Telecom \| Operating segments \| Mobility
Revenue
Revenue	19,667	19,755
International Telecom \| Operating segments \| Fixed
Revenue
Revenue	58,149	56,694
International Telecom \| Operating segments \| Carrier services
Revenue
Revenue	2,573	2,471
International Telecom \| Operating segments \| Other
Revenue
Revenue	216	187
International Telecom \| Operating segments \| Other
Revenue
Revenue	1,679	1,210
International Telecom \| Operating segments \| Managed Services
Revenue
Revenue	1,679	1,210
US Telecom \| Operating segments
Revenue
Revenue	27,299	21,493
Depreciation and amortization	5,886	5,598
Operating income (loss)	2,193	(3,506)
Segment Assets
Cash, Cash equivalents, and Investments	36,052		38,240
Total current assets	61,191		54,207
Fixed assets, net	64,710		69,184
Goodwill	35,270		35,270
Total assets	224,363		222,356
Total current liabilities	26,910		24,905
Capital Expenditures
Capital expenditures	1,972	3,075
US Telecom \| Operating segments \| Communication services
Revenue
Revenue	27,291	21,358
US Telecom \| Operating segments \| Mobility
Revenue
Revenue	4,125	3,909
US Telecom \| Operating segments \| Fixed
Revenue
Revenue	3,103	763
US Telecom \| Operating segments \| Carrier services
Revenue
Revenue	20,063	16,686
US Telecom \| Operating segments \| Other
Revenue
Revenue	8	135
US Telecom \| Operating segments \| Managed Services
Revenue
Revenue	8	135
Renewable Energy \| Operating segments
Revenue
Revenue	1,322	1,490
Depreciation and amortization	614	616
Operating income (loss)	(456)	(203)
Segment Assets
Cash, Cash equivalents, and Investments	23,858		25,054
Total current assets	26,455		27,534
Fixed assets, net	45,233		48,421
Total assets	72,405		76,723
Total current liabilities	1,660		$ 2,745
Capital Expenditures
Capital expenditures	720	609
Renewable Energy \| Operating segments \| Other
Revenue
Revenue	1,322	1,490
Renewable Energy \| Operating segments \| Renewable Energy
Revenue
Revenue	$ 1,322	$ 1,490

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