Note 8 - Derivative Instruments (Details Textual) $ in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) Contract	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) Contract oz	Sep. 30, 2024 USD ($)	Sep. 30, 2025 CAD ($) Contract
Derivative [Line Items]
Maximum Allocation of Forecasted CAD-demonimated Operating Costs	75.00%		75.00%		75.00%
Forecasted CAD-denominated Operating Costs to be Hedged, Term (Year)			5 years
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 700	$ 1,500	$ 3,500	$ 3,000
Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months	8,600		8,600
Derivative, Gain (Loss) on Derivative, Net, Total	8,500	600	9,800	8,800
Other Comprehensive Income (Loss) [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total			$ 100
Casa Berardi [Member]
Derivative [Line Items]
Derivative instrument gold put option purchased | oz			4,000
Casa Berardi [Member] | Minimum [Member]
Derivative [Line Items]
Assets Needed for Immediate Settlement, Aggregate Fair Value	3,000		$ 3,000
Casa Berardi [Member] | Maximum [Member]
Derivative [Line Items]
Assets Needed for Immediate Settlement, Aggregate Fair Value	$ 4,840		$ 4,840
Foreign Exchange Forward [Member]
Derivative [Line Items]
Derivative, Notional Amount					$ 2.5
Derivative, Forward Exchange Rate	0.013657		0.013657		0.013657
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	$ 1,800		$ 1,800
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	$ 1,600		$ 1,600
Foreign Exchange Forward [Member] | Casa Berardi [Member]
Derivative [Line Items]
Derivative, Notional Amount					$ 6.5
Cash Operating Expenditure					$ 53.2
Derivative, Forward Exchange Rate	0.013399		0.013399		0.013399
Exchange Rate	0.013248		0.013248		0.013248
Foreign Exchange Forward [Member] | Keno Hill [Member]
Derivative [Line Items]
Derivative, Notional Amount					$ 35.8
Cash Operating Expenditure					$ 65.5
Derivative, Forward Exchange Rate	0.013934		0.013934		0.013934
Exchange Rate	0.013821		0.013821		0.013821
Foreign Exchange Forward [Member] | Casa Berardi and Keno Hill [Member]
Derivative [Line Items]
Derivative, Notional Amount					$ 4.2
Derivative, Forward Exchange Rate	0.01392		0.01392		0.01392
Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] | Casa Berardi [Member]
Derivative [Line Items]
Derivative, Number of Instruments Held, Total | Contract	246		246		246
Derivative, Notional Amount	$ 122,900		$ 122,900		$ 167.7
Foreign Exchange Forward [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives	2,000	500	3,500	1,900
Price Risk Derivative [Member]
Derivative [Line Items]
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	8,900		8,900
Settlement Under Collars [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total	6,300		6,500
Unsettled Concentrate Sales Contracts [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total	14,000	600	16,000	8,800
Price Risk Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	5,100	$ 2,100	10,800	$ 7,100
Commodity Contract [Member]
Derivative [Line Items]
Derivative Liability, Subject to Master Netting Arrangement, before Offset of Collateral, Total	13,800		13,800
Derivative, Fair Value, Obligations Under the Agreements	$ 13,800		13,800
Zinc Contract 2022 [Member] | Other Comprehensive Income (Loss) [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total			17,400
Zinc and Lead Contract 2023 [Member] | Other Comprehensive Income (Loss) [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total			$ 8,500