Commitment and Contigencies (Details Textual) (USD $)	3 Months Ended			3 Months Ended			3 Months Ended
	Mar. 31, 2012 Agreements oz	Dec. 31, 2011	Jan. 21, 2009	Mar. 31, 2012 Rochester [Member] Employees	Mar. 31, 2011 Rochester [Member]	Jul. 07, 1995 Echo Bay [Member] oz	Mar. 31, 2012 Kensington [Member]	Jul. 07, 1995 Kensington [Member]	Jul. 07, 1995 Coeur Alaska Inc [Member]
Commitment and Contingencies (Textual) [Abstract]
Employment for mining and crushing operation				200
Total benefit expected under termination plan				$ 4,600,000
Acquisition of ownership interest						50.00%		100.00%
Volume related to net smelter return royalty of future gold production						1,000,000
Purchase price and construction and development expenses									32,500,000
Minimum royalty range for gold price per ounce							1.00%
Gold price per ounce for minimum royalty range							400
Maximum royalty range for gold price per ounce				5.00%			2.50%
Gold price per ounce for maximum royalty range				23.60			475
Royalty expenses				600,000	300,000
Additional Commitment and Contingencies (Textual) [Abstract]
Number of labor agreements in South America	2
Percentage of labor force covered by collective bargaining agreements	14.00%
Accrued obligations postemployment benefits	$ 7,200,000	$ 7,400,000
Royalty to be capped in terms of ounces of production	1,000,000
Purchased royalty			50.00%
Royalty agreement minimum obligation for the period	400,000
Royalty Agreement Period			8 years
Royalty Agreement Minimum Obligation for Per Month	4,167