Note 4 - Commitments, Contingencies and Obligations (Details Textual) - USD ($)		1 Months Ended		3 Months Ended	12 Months Ended	27 Months Ended
	Apr. 12, 2013	Aug. 31, 2012	Jun. 30, 2011	Mar. 31, 2017	Dec. 31, 2014	Dec. 31, 2014
Contractual Obligations				$ 1,800,000
Commitments For Capital Lease Payments				12,300,000
Surety Bonds				112,800,000
Lucky Friday [Member]
Open Purchase Orders				200,000
Casa Berardi [Member]
Open Purchase Orders				2,100,000
Greens Creek [Member]
Open Purchase Orders				9,500,000
Senior Notes [Member]
Proceeds from Issuance of Debt	$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage	6.875%
Debt Instrument, Increase (Decrease), Net					$ 6,500,000
Johnny M Mine Area near San Mateo, New Mexico [Member]
Payment Of Response Costs		$ 1,100,000				$ 1,100,000
Estimated Response Costs				5,600,000
Liability for Remediation				5,600,000
Johnny M Mine Area near San Mateo, New Mexico [Member] | Minimum [Member]
Estimated Alternative Response Costs				0
Johnny M Mine Area near San Mateo, New Mexico [Member] | Maximum [Member]
Estimated Alternative Response Costs				$ 221,000,000
Carpenter Snow Creek Superfund Site, Cascade County, Montana [Member]
Estimated Response Costs			$ 4,500,000
Estimated Future Response Cost			$ 100,000,000
Joint Venture [Member] | Rio Grande Silver Inc and Emerald Mining and Leasing LLC [Member]
Equity Method Investment, Ownership Percentage				70.00%
Maximum Environmental Remediation Obligation				$ 2,500,000