Derivative Financial Instruments and Fair Value of Financial Instruments (Details 1) (USD $) In Thousands	Jun. 30, 2011	Dec. 31, 2010
Forward foreign exchange contracts [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	$ 830	$ 328
Forward foreign exchange contracts [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0	0
Forward foreign exchange contracts [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	527	323
Forward foreign exchange contracts [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Forward foreign exchange contracts [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Forward foreign exchange contracts [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Gold lease facility [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value		0
Gold lease facility [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value		0
Gold lease facility [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		2,213
Gold lease facility [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold lease facility [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold lease facility [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold forward contracts [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value		425
Gold forward contracts [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value		0
Gold forward contracts [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold forward contracts [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold forward contracts [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Gold forward contracts [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value		0
Silver ounces received from Mandalay [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	1,378	531
Silver ounces received from Mandalay [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	680	1,063
Silver ounces received from Mandalay [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver ounces received from Mandalay [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver ounces received from Mandalay [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver ounces received from Mandalay [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Palmarejo gold production royalty [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value		0
Palmarejo gold production royalty [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0
Palmarejo gold production royalty [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0
Palmarejo gold production royalty [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Palmarejo gold production royalty [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Palmarejo gold production royalty [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	33,425	28,745
Palmarejo gold production royalty [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	131,466	133,258
Gold Put Purchase And Call Sold Options Net [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0	0
Gold Put Purchase And Call Sold Options Net [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0	0
Gold Put Purchase And Call Sold Options Net [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	1,449	1,471
Gold Put Purchase And Call Sold Options Net [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	11,623	13,277
Gold Put Purchase And Call Sold Options Net [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Gold Put Purchase And Call Sold Options Net [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver And Gold Concentrate Sales Agreements [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	30	1,703
Silver And Gold Concentrate Sales Agreements [Member] | Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	0	0
Silver And Gold Concentrate Sales Agreements [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	1,223	23
Silver And Gold Concentrate Sales Agreements [Member] | Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver And Gold Concentrate Sales Agreements [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Silver And Gold Concentrate Sales Agreements [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Prepaid expenses and other [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	2,238	2,987
Other non-current Assets [Member]
Fair value of the derivative instruments
Derivative Asset, Fair Value	680	1,063
Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	3,199	4,030
Other long-term liabilities [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	11,623	13,277
Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	33,425	28,745
Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	$ 131,466	$ 133,258