Property, Plant and Equipment (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Capital Expenditures
Capital expenditures	$ 21,784	$ 29,972	$ 32,238	$ 31,647	$ 40,207	$ 38,099	$ 25,764	$ 15,918	$ 115,641		$ 119,988		$ 155,994
Palmarejo [Member]
Capital Expenditures
Capital expenditures									38,456	[1]	36,976	[1]	54,226	[1]
San Bartolome [Member]
Capital Expenditures
Capital expenditures									25,672	[1]	17,731	[1]	6,159	[1]
Kensington [Member]
Capital Expenditures
Capital expenditures									36,994	[1]	34,013	[1]	92,730	[1]
Rochester [Member]
Capital Expenditures
Capital expenditures									11,794	[1]	27,217	[1]	2,349	[1]
Martha [Member]
Capital Expenditures
Capital expenditures									1,193	[1]	3,426	[1]	100	[1]
Other [Member]
Capital Expenditures
Capital expenditures									$ 1,532	[1]	$ 625	[1]	$ 430	[1]

[1] Balance represents cash flow amounts