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INVESTMENTS (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Jun. 23, 2021 USD ($) project $ / shares shares	Dec. 31, 2020 USD ($)
Investments
Number of common shares | shares	4,963,455
Warrants received | shares	2,481,727
Proceeds from sale of investments		$ 1,266
Disposal Group | Projects in Nevada
Investments
Cash consideration received	$ 500
Price per common share for each warrant | $ / shares	$ 0.60
Disposal Group | Projects in Nevada, Limousine Butte and Cedar Wash
Investments
Number of projects sold | project	2
Marketable equity securities
Investments
Proceeds from sale of investments		$ 1,300

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644

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