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MINERAL PROPERTY INTERESTS AND PLANT AND EQUIPMENT - Quantitative and Qualitative Information (Details) - Nonrecurring - Level 3 - Gold Bar mine	3 Months Ended
	Mar. 31, 2020 $ / oz
Mineral property interests and plant and equipment
Long term gold price (in dollars per ounce)	1,430
Discounted Cash Flow | Weighted Average
Mineral property interests and plant and equipment
Discount Rate (as a percent)	9.00%
Discounted Cash Flow | Weighted Average | USA
Mineral property interests and plant and equipment
Inflation index (as a percent)	2.00%

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