Note 4 - Environmental and Reclamation Activities - Schedule of Reclamation and Closure Costs Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	$ 116,999	$ 113,231	$ 116,048	$ 108,374
Reclamation and closure costs, current	$ (8,591)	$ (9,259)
Environmental Loss Contingency, Current, Statement of Financial Position [Extensible Enumeration]	Accrued Reclamation Costs, Current	Accrued Reclamation Costs, Current
Reclamation and closure costs, long-term	$ 108,408	$ 103,972
Environmental Loss Contingency, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Mine Reclamation and Closing Liability, Noncurrent	Mine Reclamation and Closing Liability, Noncurrent
Operating Properties [Member] | Greens Creek [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	$ 37,212	$ 37,474
Operating Properties [Member] | Lucky Friday [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	13,343	13,543
Operating Properties [Member] | Casa Berardi [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	11,352	12,497
Operating Properties [Member] | Nevada Operations [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	28,171	$ 27,068
Non-Operating Properties [Member] | Keno Hill [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	$ 4,514
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]	Employee-related Liabilities, Current	Employee-related Liabilities, Current
Non-Operating Properties [Member] | San Sebastian [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	$ 1,989	$ 4,451
Non-Operating Properties [Member] | Troy Mine [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	6,980	4,813
Non-Operating Properties [Member] | Johnny M [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	8,961	8,947
Non-Operating Properties [Member] | All Other Sites [Member]
Environmental and Reclamation Activities [Line Items]
Reclamation and closure costs	$ 4,477	$ 4,438