Quarterly report pursuant to Section 13 or 15(d)

Asset Retirement and Reclamation Obligations (Details Textual)

v2.4.0.8
Asset Retirement and Reclamation Obligations (Details Textual) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2014
Estimated Future Cash Undiscounted Amount $ 17.7
Minimum [Member]
 
Discount Rate Of Asset Retirement Obligations 0.30%
Maximum [Member]
 
Discount Rate Of Asset Retirement Obligations 3.80%