Property, Plant and Equipment (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended							12 Months Ended
	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Capital Expenditures
Capital expenditures	$ 38,099	$ 25,764	$ 15,918	$ 26,555	$ 36,783	$ 45,467	$ 47,189	$ 40,207	$ 119,988	$ 155,994	$ 218,235
Palmarejo [Member]
Capital Expenditures
Capital expenditures									36,976	54,226	162,697
San Bartolome [Member]
Capital Expenditures
Capital expenditures									17,731	6,159	11,091
Kensington [Member]
Capital Expenditures
Capital expenditures									34,013	92,730	41,289
Rochester [Member]
Capital Expenditures
Capital expenditures									27,217	2,349	310
Martha [Member]
Capital Expenditures
Capital expenditures									3,426	100	1,575
Other [Member]
Capital Expenditures
Capital expenditures									$ 625	$ 430	$ 1,273