Inventory and Ore on Leach Pads - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Inventory [Line Items]
Inventory Write-down	$ 10,381	$ 15,447
Silvertip [Member]
Inventory [Line Items]
Inventory Write-down	$ 10,400

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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