Fair Value Measurements Fair Value Measurements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 Property, Plant and Equipment [Member] Minimum [Member] Discounted Cash Flow [Member] Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2014 Property, Plant and Equipment [Member] Maximum [Member] Discounted Cash Flow [Member] Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2014 Mining Properties [Member] Minimum [Member] Discounted Cash Flow [Member] Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2014 Mining Properties [Member] Maximum [Member] Discounted Cash Flow [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Other Derivative Instrument [Member]	Dec. 31, 2013 Other Derivative Instrument [Member] Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative fair value of derivative liability					$ 1,590	$ 0
Discount Rate	8.50%	10.50%	8.50%	10.50%