COMMITMENTS AND CONTINGENCIES - (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Other Commitments [Line Items]
Asset retirement obligation	$ 31,865	$ 44,117
Loss Contingency, Damages Sought, Value	4,600
Loss Contingency, Damages Paid, Value	1,400
Loss Contingency, Damages Held In Escrow, Value	3,200
Mining Properties and Mineral Rights
Other Commitments [Line Items]
Renewal costs	1,510
Canyon Project
Other Commitments [Line Items]
Loss contingency, estimate of possible loss	20,350	20,000
Asset retirement obligation	$ 61,450	$ 74,270

Loss Contingency, Damages Held In Escrow, Value

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of damages paid to the plaintiff in the legal matter.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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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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