Income and Mining Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Examination [Line Items]
Income (loss) before income and mining taxes	$ (13,053)	$ 13,729	$ 16,656	$ (4,561)
Income tax provision from continuing operations
Income and mining tax benefit (expense)	2,098	768	(8,948)	(1,338)
UNITED STATES
Income Tax Examination [Line Items]
United States	(6,493)	119	14,221	(9,242)
Income tax provision from continuing operations
Income and mining tax benefit (expense)	(1,588)	1,810	377	2,342
ARGENTINA
Income Tax Examination [Line Items]
Foreign	(129)	4,453	(457)	3,438
Income tax provision from continuing operations
Income and mining tax benefit (expense)	(945)	1,793	(2,070)	250
Mexico
Income Tax Examination [Line Items]
Foreign	(2,195)	3,353	6,455	(4,155)
Income tax provision from continuing operations
Income and mining tax benefit (expense)	4,766	(4,316)	14,689	(4,333)
BOLIVIA
Income Tax Examination [Line Items]
Foreign	(2,001)	4,016	(1,530)	6,062
Income tax provision from continuing operations
Income and mining tax benefit (expense)	(245)	(848)	(214)	722
Other Countries
Income Tax Examination [Line Items]
Foreign	(2,235)	1,788	(2,033)	(664)
Income tax provision from continuing operations
Income and mining tax benefit (expense)	$ (4,086)	$ 793	$ (3,834)	$ 2,357