Note 4 - Business Segments, Sales of Products and Significant Customers - Information About Reportable Segments (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net sales		$ 807,473	$ 691,873	$ 673,266
Net sales		807,473	691,873	673,266
Income (loss) from operations	[1]	83,420	66,978	(46,678)
Capital additions (excluding non-cash items		109,048	91,016	121,421
Depreciation, depletion and amortization:	[1]	171,793	148,110	191,451
Other significant non-cash items		(6,305)	12,851	9,294
Identifiable assets	[1]	2,728,808	2,700,210	2,660,774
Greens Creek [Member]
Net sales		384,843	327,820	299,722
Net sales		384,843	327,820	299,722
Income (loss) from operations	[1]	164,666	114,607	87,232
Capital additions (excluding non-cash items		23,883	19,685	29,570
Depreciation, depletion and amortization:		48,710	49,692	47,587
Other significant non-cash items		3,653	3,103	2,868
Identifiable assets		589,944	610,360	639,047
Lucky Friday [Member]
Net sales		131,488	63,025	16,621
Net sales		131,488	63,025	16,621
Income (loss) from operations		31,683	(1,711)	(12,520)
Capital additions (excluding non-cash items		29,885	25,776	8,989
Depreciation, depletion and amortization:		26,846	11,473	1,175
Other significant non-cash items		1,048	881	996
Identifiable assets		516,545	520,463	440,615
Casa Berardi [Member]
Net sales		245,152	209,224	192,944
Net sales		245,152	209,224	192,944
Income (loss) from operations	[1]	5,807	10,379	(25,432)
Capital additions (excluding non-cash items		49,617	40,840	36,059
Depreciation, depletion and amortization:	[1]	80,744	60,552	65,893
Other significant non-cash items		1,284	(1,741)	5,203
Identifiable assets	[1]	701,868	727,008	726,977
Nevada Operations [Member]
Net sales		45,814	58,898	107,769
Net sales		45,814	58,898	107,769
Income (loss) from operations		(46,115)	(6,674)	(49,224)
Capital additions (excluding non-cash items		5,470	4,003	42,953
Depreciation, depletion and amortization:		15,341	22,845	67,024
Other significant non-cash items		7,740	2,039	2,911
Identifiable assets		468,985	513,309	528,466
Other Segments [Member]
Net sales		176	32,906	56,210
Net sales		176	32,906	56,210
Income (loss) from operations		(72,621)	(49,623)	(46,734)
Capital additions (excluding non-cash items		193	712	3,850
Depreciation, depletion and amortization:		152	3,548	9,772
Other significant non-cash items	[1]	(20,030)	8,569	(2,684)
Identifiable assets		$ 451,466	$ 329,070	$ 325,669

[1] Amounts reported as of and for the years ended December 31, 2020 and 2019 have been revised. See Note 3 for more information.