Property, plant, and equipment and assets held-for-sale, net - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) mill	Dec. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) mill	Jun. 04, 2024 USD ($)
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 2,000	$ 2,200
Plant and equipment, gross	88,441	$ 87,861
Gross proceeds from sale				$ 3,600
Held-for-sale | Ball Mills
Property, Plant and Equipment [Line Items]
Number of mills to sell | mill			1
Gross proceeds from sale			$ 4,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Ball Mills
Property, Plant and Equipment [Line Items]
Reduction in assets held for sale	2,800
Gain on sale	$ 700
SAG Mill
Property, Plant and Equipment [Line Items]
Number of mills | mill	1
Construction in progress, leach pad
Property, Plant and Equipment [Line Items]
Plant and equipment, gross	$ 35,000