Note 4 - Environmental and Reclamation Activities (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

Schedule of Accrued Liabilities [Table Text Block]

	2016			2015
Operating properties:
Greens Creek	$	39,014		$	41,338
Lucky Friday		9,194			5,212
Casa Berardi		5,475			5,494
San Sebastian		5,425			1,189
Non-operating properties:
Troy mine		16,167			17,295
South Dakota and Colorado Superfund Sites		—			16,300
Johnny M		5,830			5,830
Republic		1,500			774
All other sites		2,975			2,106
Total		85,580			95,538
Reclamation and closure costs, current		(5,653	)		(20,989	)
Reclamation and closure costs, long-term	$	79,927		$	74,549

Accrued Reclamation and Closure Cost Liability Activity [Table Text Block]

Balance at January 1, 2014	$	105,191
Accruals for estimated costs		6,863
Accretion expense		3,089
Revision of estimated cash flows due to changes in reclamation plans		675
Payment of reclamation obligations		(58,568	)
Balance at December 31, 2014		57,250
Accruals for estimated costs		15,114
Accretion expense		1,904
Revision of estimated cash flows due to changes in reclamation plans		4,112
Addition due to development and production at our San Sebastian unit		1,189
Liability addition due to acquisition of Revett		17,513
Payment of reclamation obligations		(1,544	)
Balance at December 31, 2015		95,538
Accruals for estimated costs		672
Accretion expense		3,191
Revision of estimated cash flows due to changes in reclamation plans		2,759
Liability addition due to acquisition of Mines Management		1,124
Payment of reclamation obligations		(17,704	)
Balance at December 31, 2016	$	85,580

Schedule of Change in Asset Retirement Obligation [Table Text Block]

	2016			2015
Balance January 1	$	53,233		$	46,539
Changes in obligations due to changes in reclamation plans		2,760			4,112
Addition due to development and production at our San Sebastian unit		—			1,189
Accretion expense		3,191			1,904
Payment of reclamation obligations		(76	)		(511	)
Balance at December 31	$	59,108		$	53,233