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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Ore Stockpile Inventory (Details) | 12 Months Ended | 64 Months Ended | 76 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018
El Gallo 1 mine |  |  |
Stockpiles, Material on Leach Pads, In-process Inventory, Precious Metals Inventory and Materials and Supplies |  |  |
Cumulative metallurgical recovery rate for gold production (as a percent) |  | 57.00% | 61.00%
Minimum |  |  |
Stockpiles, Material on Leach Pads, In-process Inventory, Precious Metals Inventory and Materials and Supplies |  |  |
Recovery percentage of leach pads of the recoverable ounces in the first year of leaching | 50.00% |  |
Maximum |  |  |
Stockpiles, Material on Leach Pads, In-process Inventory, Precious Metals Inventory and Materials and Supplies |  |  |
Recovery percentage of leach pads of the recoverable ounces in the first year of leaching | 95.00% |  |

X
- Definition Represents the typical recovery percentage of recoverable ounces of leach pad operations in the first years of production. + References No definition available. + Details
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- Definition Represents the cumulative, life-of-mine recovery percentage of recoverable ounces for the Company leach pad operation. + References No definition available. + Details
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- Details
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- Details
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- Details
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