Note 6 - Business Segments (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)
Number of Reportable Segments			4
Employee Labor Strike Related Costs	$ 8,024		$ 9,605
Lucky Friday [Member] | Care and Maintenance Costs [Member]
Employee Labor Strike Related Costs			7,600
Lucky Friday [Member] | Non-cash Depreciation Expense [Member]
Employee Labor Strike Related Costs			$ 2,000