Litigation and Other Events (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Oct. 14, 2009 m
Litigation and Other Events (Textual) [Abstract]
Settlement amount under law	$ 3.5
Temporarily suspending mining activities above the elevation		4,400
Restriction on Mining	Temporary Restriction on Mining above 4,400 Meters at San Bartolomé
Rochester [Member]
Litigation and Other Events (Additional Textual) [Abstract]
Number of unpatented mining claims	447
Approximate area of federal lands covering for unpatented mining claims	8,600