Income and Mining Taxes (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income tax provision from continuing operations
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest	$ (13,117)	$ (48,323)	$ (95,496)	$ (36,175)
Income tax provision from continuing operations	16,583	2,058	18,650	(32,860)
United States - Alternative minimum tax [Member]
Income Tax Examination [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	(14,954)	(33,250)	(75,168)	(95,146)
Income tax provision from continuing operations
Federal tax expense (benefit)	739	5,259	447	718
Argentina [Member]
Income tax provision from continuing operations
Income (Loss) from Continuing Operations before Income Taxes, Foreign	(935)	(2,092)	(3,828)	(9,073)
Foreign tax expense (benefit)	1,539	6	5,622	(38)
Mexico [Member]
Income tax provision from continuing operations
Income (Loss) from Continuing Operations before Income Taxes, Foreign	(283)	(18,969)	(28,999)	39,787
Foreign tax expense (benefit)	17,003	1,885	20,831	(17,586)
Bolivia [Member]
Income tax provision from continuing operations
Income (Loss) from Continuing Operations before Income Taxes, Foreign	3,199	4,842	11,848	26,470
Foreign tax expense (benefit)	(2,969)	(4,598)	(7,937)	(13,482)
Other Countries [Member]
Income tax provision from continuing operations
Income (Loss) from Continuing Operations before Income Taxes, Foreign	(144)	1,146	651	1,787
Foreign tax expense (benefit)	$ 271	$ (494)	$ (313)	$ (2,472)