Note 6 - Business Segments - Identifiable Assets by Reporting Segments (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Identifiable assets	$ 2,379,156	$ 2,371,677
Greens Creek [Member]
Identifiable assets	674,210	681,303
Lucky Friday [Member]
Identifiable assets	431,331	442,829
Casa Berardi [Member]
Identifiable assets	807,180	806,044
San Sebastian [Member]
Identifiable assets	43,268	33,608
Other Segments [Member]
Identifiable assets	$ 423,167	$ 407,893