v2.3.0.15
Commitments And Contingencies (Details) (USD $)
Sep. 30, 2011
Jun. 20, 2011
Dec. 31, 2010
Commitment for long-term lease contract  $ 600,000,000
Issued court judgment 196,000,000 
Recorded liability due to court judgment133,000,000  
Recorded receivable due to indemnification agreement133,000,000  
Devon [Member]
   
Issued court judgment $ 133,000,000