Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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 accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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MINERAL PROPERTIES AND PROPERTY, PLANT AND EQUIPMENT - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 189,586		$ 189,586		$ 117,754
Less: accumulated depreciation	(54,205)		(54,205)		(47,959)
Property, Plant and Equipment, Net, Total	135,381		135,381		69,795
Depreciation	1,820	$ 1,300	4,600	$ 3,730
Land
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	23,773		23,773		7,416
Plant facilities
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 76,389		$ 76,389		66,053
Plant facilities \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	12 years		12 years
Plant facilities \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	15 years		15 years
Mining equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 43,805		$ 43,805		28,329
Mining equipment \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	5 years		5 years
Mining equipment \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	10 years		10 years
Light trucks and utility vehicles
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 5,438		$ 5,438		4,635
Estimated Useful Lives	5 years		5 years
Water rights
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 11,273		$ 11,273		0
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 2,286		$ 2,286		1,985
Office furniture and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	4 years		4 years
Office furniture and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Estimated Useful Lives	7 years		7 years
Construction-in-progress
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 26,622		$ 26,622		$ 9,336
White Mesa Mill
Property, Plant and Equipment [Line Items]
Depreciation	$ 680	$ 570	$ 1,890	$ 1,570