GOODWILL AND INTANGIBLE ASSETS - Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	$ 60,691	$ 60,691
Accumulated impairment	(20,587)	0
Goodwill, Total	40,104	60,691	$ 60,691
International Telecom
Changes in the carrying amount of goodwill, by operating segment
Goodwill, Gross	25,423	25,423
Accumulated impairment	(20,587)	0
Goodwill, Total	4,836	25,423	25,423
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, Total			$ 0

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.

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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.

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