Note 6. Business Segments (Detail) - Information About Reportable Segments (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	$ 81,871	$ 120,543	$ 240,043	$ 374,767
Income from operations:
Income (loss) from operations	8,726	43,489	31,681	166,015
Greens Creek [Member]
Net sales to unaffiliated customers:
Net sales to unaffiliated customers	81,871	77,031	239,794	260,650
Income from operations:
Income (loss) from operations	34,834	37,098	105,529	140,661
Lucky Friday [Member]
Net sales to unaffiliated customers:
Net sales to unaffiliated customers		43,512	249	114,117
Income from operations:
Income (loss) from operations	(6,147)	27,662	(18,588)	68,170
Other Segment Income(Loss) [Member]
Income from operations:
Income (loss) from operations	$ (19,961)	$ (21,271)	$ (55,260)	$ (42,816)