Note 4 -Business Segments, Sales of Products and Significant Customers (Additional Information) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2025 USD ($) Segment oz T	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment	4
Writedown of property, plant and equipment	$ 0	$ 14,574	$ 0
Derivative, loss on derivative	29,600	1,300	19,700
Actual Costs of Work Performed	8,200	8,800	3,600
Trade	170,230	31,515	19,400
Allowance for doubtful accounts	$ 0	$ 0	$ 0
Derivative, loss, statement of income or comprehensive income [Extensible Enumeration]	Unrealized (loss) gain on derivative contracts designated as hedge transactions	Unrealized (loss) gain on derivative contracts designated as hedge transactions	Unrealized (loss) gain on derivative contracts designated as hedge transactions
Debt Instrument, Payment Terms	Payment terms are 30 days after receipt of an invoice by CIRNAC. CIRNAC has the ability to cancel the contract with or without cause by providing written notice to the Company. ERDC is owed for work performed as of the date of cancellation.
Lucky Friday [Member]
Segment Reporting Information [Line Items]
Business interruption insurance proceeds received		$ 50,000
Writedown of property, plant and equipment	$ 13,900
Casa Berardi [Member]
Segment Reporting Information [Line Items]
Business interruption insurance proceeds received	$ 5,500
Silver Contracts [Member]
Segment Reporting Information [Line Items]
Metals contained in concentrates (Ounce) | oz	3,500,000
Gold [Member]
Segment Reporting Information [Line Items]
Metals contained in concentrates (Ounce) | oz	2,272
Zinc [Member]
Segment Reporting Information [Line Items]
Metals contained in concentrates (Ounce) | T	14,028
Lead [Member]
Segment Reporting Information [Line Items]
Metals contained in concentrates (Ounce) | T	8,322