Note 8 - Derivative Instruments (Details Textual) $ in Millions	3 Months Ended
	Mar. 31, 2025 USD ($) Contract oz $ / oz	Mar. 31, 2024 USD ($)	Mar. 31, 2025 CAD ($) Contract
Derivative [Line Items]
Maximum Allocation of Forecasted CAD-demonimated Operating Costs	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	$ 1,800,000	$ 400,000
Gain (Loss) on Components Excluded from Assessment of Foreign Currency Cash Flow Hedge Effectiveness	0	0
Price Risk Cash Flow Hedge Unrealized Gain (Loss) to be Reclassified During Next 12 Months	12,100,000
Derivative, Gain (Loss) on Derivative, Net, Total	5,100,000	3,100,000
Put Option
Derivative [Line Items]
Derivative, Notional Amount	$ 600,000
Minimum [Member]
Derivative [Line Items]
Price per ounce | $ / oz	31.4
Maximum [Member]
Derivative [Line Items]
Price per ounce | $ / oz	33.97
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative instrument gold put option purchased | oz	590,000
Foreign Exchange Forward [Member]
Derivative [Line Items]
Derivative, Notional Amount			$ 7.8
Derivative, Forward Exchange Rate	0.013732		0.013732
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	$ 6,500,000
Foreign Currency Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months	$ 5,000,000
Foreign Exchange Forward [Member] | Casa Berardi [Member]
Derivative [Line Items]
Derivative, Notional Amount			$ 12.6
Derivative, Forward Exchange Rate	0.013432		0.013432
Foreign Exchange Forward [Member] | Keno Hill [Member]
Derivative [Line Items]
Derivative, Notional Amount			$ 53.4
Derivative, Forward Exchange Rate	0.013985		0.013985
Foreign Exchange Forward [Member] | Casa Berardi and Keno Hill [Member]
Derivative [Line Items]
Derivative, Notional Amount			$ 166.4
Derivative, Forward Exchange Rate	0.01346		0.01346
Foreign Exchange Forward [Member] | Casa Berardi and Keno Hill [Member]
Derivative [Line Items]
Derivative, Notional Amount			$ 5.4
Derivative, Forward Exchange Rate	0.014054		0.014054
Foreign Exchange Forward [Member] | Designated as Hedging Instrument [Member] | Casa Berardi [Member]
Derivative [Line Items]
Derivative, Number of Instruments Held, Total | Contract	328		328
Derivative, Notional Amount	$ 208,300,000		$ 285.6
Foreign Exchange Forward [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Unrealized Gain (Loss) on Derivatives	100,000	1,900,000
Price Risk Derivative [Member]
Derivative [Line Items]
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	5,200,000
Derivative, Gain (Loss) on Derivative, Net, Total	$ 33.97
Price per ounce | $ / oz	31.4
Unsettled Concentrate Sales Contracts [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total	$ (5,300,000)	3,100,000
Price Risk Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	2,200,000	$ 1,900,000
Commodity Contract [Member]
Derivative [Line Items]
Derivative Liability, Subject to Master Netting Arrangement, before Offset of Collateral, Total	10,500,000
Derivative, Fair Value, Obligations Under the Agreements	10,500,000
Zinc Contract 2022 [Member] | Other Comprehensive Income (Loss) [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total	17,400,000
Zinc and Lead Contract 2023 [Member] | Other Comprehensive Income (Loss) [Member]
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net, Total	$ 8,500,000