RECLAMATION AND REMEDIATION LIABILITIES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Sep. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Asset Retirement Obligation [Line Items]
Reclamation and remediation costs	$ 7,135		$ 2,414		$ 81,305	$ 280,146
Incurred remediation costs				$ 272,900
Changes in estimates					65,363	11,054
Total reclamation costs
Asset Retirement Obligation [Line Items]
Reclamation and remediation costs	7,059		2,414		27,668	18,472
Reclamation adjustments and other	0		0		9,419	11,229
Changes in estimates					11,856	11,054
Total remediation costs
Asset Retirement Obligation [Line Items]
Reclamation and remediation costs	76		0		53,637	261,674
Reclamation adjustments and other	$ 76		$ 0		53,637	261,674
Changes in estimates					53,507	$ 0
Çöpler Incident
Asset Retirement Obligation [Line Items]
Incurred remediation costs				22,500
Reclamation adjustments and other		$ 62,900
Changes in estimates					12,900
Çöpler Incident \| Total reclamation costs
Asset Retirement Obligation [Line Items]
Reclamation adjustments and other		$ 9,400
Changes in estimates					9,400
Çöpler Incident \| Total remediation costs
Asset Retirement Obligation [Line Items]
Changes in estimates					$ 53,500
Çöpler Incident \| Minimum
Asset Retirement Obligation [Line Items]
Reclamation and remediation costs				250,000
Çöpler Incident \| Maximum
Asset Retirement Obligation [Line Items]
Reclamation and remediation costs				$ 300,000