GOODWILL AND INTANGIBLE ASSETS - Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	$ 60,691	$ 63,970
Accumulated impairment	0	(3,279)
Goodwill, Total	60,691	60,691	$ 63,970
International Telecom
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	24,326	24,326
Accumulated impairment	0	0
Goodwill, Total	24,326	24,326	24,326
US Telecom
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	35,268	35,268
Accumulated impairment	0	0
Goodwill, Total	35,268	35,268	35,268
Renewable Energy
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	0	3,279
Accumulated impairment	0	(3,279)
Goodwill, Total	$ 0	$ 0	$ 3,279

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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Amount before 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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