INVENTORIES - Components of Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Inventory [Line Items]
Work-in-process	$ 6,052	$ 3,850
Finished goods	16,107	20,745
Total current inventories	586,162	464,074
Inventories	495,035	291,212
Materials and supplies
Inventory [Line Items]
Raw materials	136,318	113,752
Stockpiled ore
Inventory [Line Items]
Raw materials	77,477	72,561
Inventories	245,288	246,536
Leach pad inventory
Inventory [Line Items]
Raw materials	350,208	253,166
Inventories	$ 249,747	$ 44,676

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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- 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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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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