Note 6 - Business Segments (Details) - Information About Reportable Segments (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	$ 135,507	$ 106,629	$ 378,796	$ 268,409
Income (loss) from operations:
Income (loss) from operations	6,271	1,741	19,215	(33,094)
Greens Creek [Member]
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	67,763	64,845	186,808	207,576
Income (loss) from operations:
Income (loss) from operations	8,874	15,310	28,724	51,164
Lucky Friday [Member]
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	27,883	14,395	71,740	23,324
Income (loss) from operations:
Income (loss) from operations	9,007	402	20,105	(6,210)
Casa Berardi [Member]
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	39,861	27,389	120,248	37,509
Income (loss) from operations:
Income (loss) from operations	395	572	4,940	(12,784)
Other Segments [Member]
Income (loss) from operations:
Income (loss) from operations	$ (12,005)	$ (14,543)	$ (34,554)	$ (65,264)