Commitment and Contigencies (Details Textual) (USD $)	3 Months Ended			3 Months Ended		6 Months Ended			3 Months Ended
	Jun. 30, 2012 oz Agreements	Dec. 31, 2011	Jan. 21, 2009	Jun. 30, 2012 Rochester [Member] Employees	Jun. 30, 2011 Rochester [Member]	Jun. 30, 2012 Rochester [Member]	Jun. 30, 2011 Rochester [Member]	Jul. 07, 1995 Echo Bay [Member] oz	Jun. 30, 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				$ 4,800,000
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				500,000	0	600,000	900,000
Additional Commitment and Contingencies (Textual) [Abstract]
Number of labor agreements in South America	2
Percentage of labor force covered by collective bargaining agreements	11.00%
Accrued obligations postemployment benefits	$ 7,300,000	$ 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