XML 23 R47.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Litigation (Details) (USD $)
1 Months Ended
Sep. 30, 2010
Aug. 31, 2010
Jun. 30, 2011
Feb. 14, 2011
Nov. 30, 2008
Litigation (Textuals) [Abstract]          
Pending lawsuits and claims     20    
Remediation program     $ 40,000,000    
Financial compensation for purported damages on mining engineer's report         18,900,000,000
Assessment for purported unjust enrichment on mining engineer's report         8,400,000,000
Court order requiring the parties to provide their positions on damages within (in days)   45 days      
Approximate damages on plaintiffs' submission, Maximum 76,000,000,000        
Approximate damages on plaintiffs' submission, Minimum 16,000,000,000        
Approximate unjust enrichment on plaintiffs' submission, Maximum 38,000,000,000        
Approximate unjust enrichment on plaintiffs' submission, Minimum 5,000,000,000        
Amount assessed in damages       8,600,000,000  
Amount assessed for plaintiffs representatives       900,000,000  
Additional amount assessed in punitive damages       $ 8,600,000,000