Derivative Financial Instruments (Details 1) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset	$ 841	$ 28
Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	186	536
Current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	3,317	4,957
Non-current portion of royalty obligation [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	3,317	4,957
Palmarejo gold production royalty [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	0	0
Concentrate sales contracts [Member] | Prepaid expenses and other [Member]
Fair value of the derivative instruments
Fair value of derivative asset	841	28
Concentrate sales contracts [Member] | Accrued liabilities and other [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	186	536
Concentrate sales contracts [Member] | Non-current portion of royalty obligation [Member]
Fair value of the derivative instruments
Derivative Liability, Fair Value	$ 0	$ 0