DESCRIPTION OF BUSINESS - Cash Commitments (Details) $ in Millions	Dec. 31, 2019 USD ($)
Cash commitments under equipment contracts
2021	$ 0.6
Total	$ 0.6
Purchase Commitment | Mining and milling equipment | POS-Minerals Corporation
Cash commitments under equipment contracts
Percentage of commitments funded	20.00%
Purchase Commitment | Mining and milling equipment | Nevada Moly LLC
Cash commitments under equipment contracts
Percentage of commitments funded	80.00%