INVENTORIES - Schedule of Inventory, Current (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Inventory [Line Items]
Inventory Write-down	$ 430	$ 0	$ 1,506
Concentrates and work-in-progress(1)		27,151		$ 25,768
Inventory Of Ore In Stockpiles		241		241
Raw materials and consumables		3,164		2,912
Inventory, net		30,556		28,921
Current		29,210		27,575
Long term - raw materials and consumables		$ 1,346		$ 1,346

Inventory, Current

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- Definition

Inventory of ore in stockpiles

+ References

No definition available.

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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.

+ References

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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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- Definition

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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