INVENTORIES - Schedule of Inventory, Current (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Inventory [Line Items]
Inventory Write-down	$ 2,330	$ 714	$ 8,412	$ 3,063
Concentrates and work-in-progress	20,790		20,790		$ 14,746
Inventory Of Ore In Stockpiles	677		677		883
Raw materials and consumables	2,797		2,797		2,693
Inventory, net	24,264		24,264		18,322
Current	22,492		22,492		16,550
Long term - raw materials and consumables	$ 1,772		$ 1,772		$ 1,772

Inventory, Current

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- Definition

Inventory of ore in stockpiles

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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- Definition

Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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- Definition

Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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- Definition

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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