LIQUIDITY - Cash Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Cash commitments under equipment contracts
Total	$ 1.8
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%
Purchase Commitment | Mining and milling equipment | Eureka Moly LLC
Cash commitments under equipment contracts
2019	$ 1.4
2020	0.4
Total	$ 1.8	$ 1.8