Quarterly report pursuant to Section 13 or 15(d)

Mineral Properties (Details Textual)

v2.4.0.8
Mineral Properties (Details Textual) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2014
Percentage Of Production Royalty On Acquisition 5.00%
Assumption Amount In Estimated Asset Reclamation Obligation $ 5.7
Allocated To Mineral Properties [Member]
 
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities 15.3
Deferred Tax Liabilites [Member]
 
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities 3.3
Asset Retirement Obligation [Member]
 
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities 5.7
Pathfinder Mines Corporation [Member]
 
Payments to Acquire Businesses, Gross 6.7
Nfu Wyoming Llc [Member] | Lost Creek Property [Member]
 
Percentage of asset acquired 100.00%
Purchased property interest $ 20