COMMITMENTS AND CONTINGENCIES - Loss Contingencies (Details)			1 Months Ended			3 Months Ended
	Sep. 30, 2019 USD ($)	Jul. 24, 2019 USD ($)	Mar. 31, 2020 USD ($)	Nov. 30, 2019 USD ($)	Jul. 31, 2011 item	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 27, 2019 USD ($)	Aug. 19, 2019 USD ($)	Aug. 18, 2019 USD ($)	Jun. 30, 2019 USD ($)	Apr. 30, 2019 USD ($)	Dec. 21, 2015 USD ($)	Jun. 30, 2013 item	Aug. 19, 2010 USD ($)
Loss Contingencies
Provision for post closure reclamation and remediation costs			$ 2,000,000			$ 2,000,000	$ 1,953,000
Loss contingency accrual			14,000,000			14,000,000	14,000,000
Permitting Considerations
Loss Contingencies
Provision for post closure reclamation and remediation costs			3,100,000			$ 3,100,000							$ 2,800,000
Environmental analysis, process term						3 years
Additional cash deposit												$ 300,000
Payment to trust						$ 300,000
Water Rights Considerations
Loss Contingencies
Number of parties appealing to the Nevada Supreme Court | item														2
The number of additional parties in suit | item					2
Ranchers
Loss Contingencies
Source from available cash		$ 500,000
Proceeds from private placement used		500,000
Eureka Moly LLC
Loss Contingencies
Sustainability Trust fund asset amount															$ 5,600,000
Paid into trust											$ 100,000
Eureka Moly LLC | Eureka County and the DNR
Loss Contingencies
Amount paid upon execution of the settlement						50,000
Second payment payable after receipt of the water permits			50,000			50,000
Additional contributions will be made after the commencement of production			750,000			750,000
Sustainability Trust fund asset amount									$ 5,600,000	$ 4,000,000
Amount of increase in Sustainability Trust fund asset amount			1,600,000			1,600,000
Paid into trust							$ 100,000
Eureka Moly LLC | Ranchers
Loss Contingencies
Payment to trust		$ 1,000,000
Loss contingency accrual			14,000,000			$ 14,000,000
Threshold period to secure project financing						12 months
Monthly payments until financing is achieved						$ 10,000
Land and Water Rights | Eureka Moly LLC
Loss Contingencies
Amount owed to the company								$ 700,000
Reimbursement of debt	$ 200,000		300,000	$ 200,000
Equipment | Eureka Moly LLC | Minimum
Loss Contingencies
Sale of equipment			$ 400,000