Note 5 - Environmental and Reclamation Activities (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Schedule of Accrued Liabilities [Table Text Block]

	2018			2017
Operating properties:
Greens Creek	$	41,839		$	41,677
Lucky Friday		10,698			9,911
Casa Berardi		5,843			6,729
San Sebastian		7,765			5,067
Nevada Operations		23,272			—
Non-operating properties:
Troy mine		8,971			12,724
Johnny M		5,813			5,813
Republic		1,500			1,500
All other sites		2,688			2,624
Total		108,389			86,045
Reclamation and closure costs, current		(3,410	)		(6,679	)
Reclamation and closure costs, long-term	$	104,979		$	79,366

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

Balance at January 1, 2016	$	95,538
Accruals for estimated costs		705
Accretion expense		3,158
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
Accruals for estimated costs		16
Accretion expense		4,870
Revision of estimated cash flows due to changes in reclamation plans		(578	)
Payment of reclamation obligations		(3,843	)
Balance at December 31, 2017		86,045
Accruals for estimated costs		250
Accretion expense		5,309
Revision of estimated cash flows due to changes in reclamation plans		1,280
Liability addition due to acquisition of the Nevada Operations unit		19,571
Payment of reclamation obligations		(4,066	)
Balance at December 31, 2018	$	108,389

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

	2018			2017
Balance January 1	$	63,384		$	59,275
Changes in obligations due to changes in reclamation plans		1,280			(578	)
Addition due to acquisition of the Nevada Operations unit		19,571			—
Accretion expense		5,295			4,870
Payment of reclamation obligations		(113	)		(183	)
Balance at December 31	$	89,417		$	63,384