Derivative Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset	$ 4,962	$ 184
Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	1,855	1,640
Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	16,451	17,650
Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	13,810	22,688
Forward foreign exchange contracts [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset		38
Forward foreign exchange contracts [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	8	947
Forward foreign exchange contracts [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Forward foreign exchange contracts [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Palmarejo gold production royalty [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset
Palmarejo gold production royalty [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Palmarejo gold production royalty [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	16,451	17,650
Palmarejo gold production royalty [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	13,810	22,688
Put and call options, net [Member]
Fair value of the derivative instruments
Fair value of derivative asset	4,939
Derivative Liability, Fair Value	1,331
Put and call options, net [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset	4,939	135
Put and call options, net [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	1,331
Put and call options, net [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Put and call options, net [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Concentrate sales contracts [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset	23	11
Concentrate sales contracts [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	516	693
Concentrate sales contracts [Member] | Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Concentrate sales contracts [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value
Mexican peso forward purchase contracts [Member] | Forward foreign exchange contracts [Member]
Derivative [Line Items]
Foreign exchange contracts of MXP		$ 12,000