Inventory and Ore on Leach Pads - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Inventory [Line Items]
Inventory Write-down	$ 11,872	$ 27,319
Silvertip [Member]
Inventory [Line Items]
Inventory Write-down		$ 27,300

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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