INVENTORIES (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Inventory [Line Items]
Work-in-process	$ 5,820	$ 4,951
Finished goods	25,411	33,877
Total current inventories	419,749	389,416
Non-current inventories	221,358	221,617
Materials and supplies
Inventory [Line Items]
Raw materials	97,741	79,372
Non-current inventories	1,505	1,293
Stockpiled ore
Inventory [Line Items]
Raw materials	33,200	27,589
Non-current inventories	219,853	220,324
Leach pad inventory
Inventory [Line Items]
Raw materials	$ 257,577	$ 243,627

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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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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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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