INVENTORIES - Components of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Inventory [Line Items]
Work-in-process	$ 6,289	$ 7,189
Finished goods	16,499	21,324
Total current inventories	494,618	515,143
Inventories	253,073	219,808
Materials and supplies
Inventory [Line Items]
Raw materials	116,072	104,217
Inventories	0	1,669
Stockpiled ore
Inventory [Line Items]
Raw materials	58,406	77,142
Inventories	253,073	218,139
Leach pad inventory
Inventory [Line Items]
Raw materials	$ 297,352	$ 305,271

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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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.

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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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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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