v2.4.0.6
Related Party Transactions (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Significant transactions with related parties        
Operating revenues and other income $ 9 $ 11 $ 42 $ 38
Purchases 37 44 121 287
Operating expenses and selling, general and administrative expenses 52 57 133 190
Net interest expense $ 8 $ 15 $ 30 $ 47