GOODWILL (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Goodwill
Goodwill	$ 4,373	$ 136,399
Impairments of goodwill	132,026
Hamilton mining complex
Goodwill
Goodwill		$ 132,000
Impairments of goodwill	$ 132,000

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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