INVENTORIES (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Work-in-process	$ 4,951	$ 4,368
Finished goods	33,877	38,525
Total current inventories	389,416	437,034
Non-current inventories	221,617	135,200
Inventory reserves for obsolete materials and supplies inventory	8,100	7,200
Inventory write-down	0	12,100	$ 11,800
Materials and supplies
Inventory [Line Items]
Raw materials	79,372	85,766
Non-current inventories	1,293	1,700
Stockpiled ore
Inventory [Line Items]
Raw materials	27,589	25,582
Non-current inventories	220,324	133,500
Leach pad inventory
Inventory [Line Items]
Raw materials	$ 243,627	$ 282,793

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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

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Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. This amount is net of valuation reserves and adjustments.

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Amount of valuation reserve for inventory.

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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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