Derivative Financial Instruments and Fair Value of Financial Instruments (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Derivative instruments Settlement
Average forward price		$ 1,380
Average strike price	1,737.68
Forward Contracts [Member]
Derivative instruments Settlement
Notional ounces		10,000
Forward Contracts [Member] | Mexican peso forward purchase contracts [Member] | Thereafter [Member]
Derivative instruments Settlement
Fair value of foreign exchange contracts	0
Palmarejo gold production royalty [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	14,712,000
Derivative average gold price in excess of minimum contractual Deduction Rate	484
Notional ounces	30,435
Palmarejo gold production royalty [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	24,865,000
Derivative average gold price in excess of minimum contractual Deduction Rate	497
Notional ounces	50,004
Palmarejo gold production royalty [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	25,097,000
Derivative average gold price in excess of minimum contractual Deduction Rate	502
Notional ounces	50,004
Palmarejo gold production royalty [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	78,140,000
Derivative average gold price in excess of minimum contractual Deduction Rate	493
Notional ounces	158,393
Mexican peso forward purchase contracts [Member] | 2011 [Member]
Derivative instruments Settlement
Fair value of foreign exchange contracts	15,600,000
Average forward price	12.49
Mexican peso forward purchase contracts [Member] | 2012 [Member]
Derivative instruments Settlement
Fair value of foreign exchange contracts	16,800,000
Average forward price	11.70
Mexican peso forward purchase contracts [Member] | 2013 [Member]
Derivative instruments Settlement
Fair value of foreign exchange contracts	0
Average forward price	0.00
Notional ounces	0
Mexican peso forward purchase contracts [Member] | Thereafter [Member]
Derivative instruments Settlement
Average forward price	0.00
Notional ounces	0
Mexican Peso Notional Amount [Member] | 2011 [Member]
Derivative instruments Settlement
Notional ounces	194,771
Mexican Peso Notional Amount [Member] | 2012 [Member]
Derivative instruments Settlement
Notional ounces	196,568
Silver ounces received from Mandalay [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	764,000
Average forward price	18.33
Notional ounces	41,667
Silver ounces received from Mandalay [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	1,535,000
Average forward price	18.44
Notional ounces	83,333
Silver ounces received from Mandalay [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Average forward price	0.00
Notional ounces	0
Silver ounces received from Mandalay [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Average forward price	0.00
Notional ounces	0
Silver concentrate sales agreements [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	13,398,000
Derivative average price	39.28
Notional ounces	341,058
Silver concentrate sales agreements [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0.00
Notional ounces	0
Silver concentrate sales agreements [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0.00
Notional ounces	0
Silver concentrate sales agreements [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0.00
Notional ounces	0
Gold concentrates sales agreements [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	11,384,000
Derivative average price	1,524
Notional ounces	7,471
Gold concentrates sales agreements [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0
Notional ounces	0
Gold concentrates sales agreements [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0
Notional ounces	0
Gold concentrates sales agreements [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	0
Derivative average price	0
Notional ounces	0
Gold put options purchased [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	1,800,000
Average strike price	887
Notional ounces	30,000
Gold put options purchased [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	2,880,000
Average strike price	923
Notional ounces	68,000
Gold put options purchased [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	1,800,000
Average strike price	928
Notional ounces	45,000
Gold put options purchased [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	720,000
Average strike price	991
Notional ounces	77,000
Gold call options sold [Member]
Derivative instruments Settlement
Notional ounces	23,750
Gold call options sold [Member] | 2011 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	1,800,000
Average strike price	1,740
Notional ounces	30,000
Gold call options sold [Member] | 2012 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	2,880,000
Average strike price	1,817
Notional ounces	68,000
Gold call options sold [Member] | 2013 [Member]
Derivative instruments Settlement
Derivative, Notional Amount	1,800,000
Average strike price	1,827
Notional ounces	45,000
Gold call options sold [Member] | Thereafter [Member]
Derivative instruments Settlement
Derivative, Notional Amount	720,000
Average strike price	$ 1,960
Notional ounces	77,000