Income and Mining Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Examination [Line Items]
Income (loss) before income and mining taxes	$ 13,729	$ (16,937)	$ (4,561)	$ (50,157)
Income tax provision from continuing operations
Income and mining tax benefit (expense)	768	260	(1,338)	192
United States - Alternative Minimum tax [Member]
Income Tax Examination [Line Items]
United States	119	(9,764)	(9,242)	(30,471)
Income tax provision from continuing operations
Federal tax expense (benefit)	(1,810)	319	(2,342)	2,204
ARGENTINA
Income Tax Examination [Line Items]
Foreign	4,453	(656)	3,438	(1,352)
Income tax provision from continuing operations
Foreign tax expense (benefit)	(1,793)	(1)	(250)	(2)
Mexico [Member]
Income Tax Examination [Line Items]
Foreign	3,353	(5,582)	(4,155)	(15,255)
Income tax provision from continuing operations
Foreign tax expense (benefit)	4,316	548	4,333	(716)
BOLIVIA
Income Tax Examination [Line Items]
Foreign	4,016	(1,219)	6,062	(3,598)
Income tax provision from continuing operations
Foreign tax expense (benefit)	848	196	(722)	(1,211)
Other Countries [Member]
Income Tax Examination [Line Items]
Foreign	1,788	284	(664)	519
Income tax provision from continuing operations
Foreign tax expense (benefit)	$ (793)	$ (802)	$ (2,357)	$ (83)