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NATURE OF OPERATIONS (Details) - USD ($) $ in Thousands			12 Months Ended
	Mar. 10, 2021	May 23, 2019	Dec. 31, 2020	Dec. 31, 2018
Ownership interests in various mines			100.00%
Ownership interest (as a percent)			49.00%
Proceeds in connection with the equity issuance		$ 2,600		$ 918
Equity Issuances | Subsequent Events
Proceeds in connection with the equity issuance	$ 64,400
MSC | Equity Method Investment
Ownership interest (as a percent)			49.00%

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The Company's ownership interests in various mines.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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