v2.4.0.6
Derivative and Financial Instruments - Commodity Notional (Details 2)
Sep. 30, 2012
MMBbls
Dec. 31, 2011
MMBbls
Crude oil, refined products and natural gas liquids [Member]
   
Trading Activity, Gains and Losses, Net [Line Items]    
Commodity derivatives - material net exposures 0 (13)
Natural gas and power, Fixed price [Member]
   
Trading Activity, Gains and Losses, Net [Line Items]    
Commodity derivatives - material net exposures (64,000,000,000) (57,000,000,000)
Natural gas and power, Basis [Member]
   
Trading Activity, Gains and Losses, Net [Line Items]    
Commodity derivatives - material net exposures 97,000,000,000 (25,000,000,000)