v2.4.0.6
Goodwill and Intangibles - Summary of Carrying Value of Intangible Assets (Detail) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2011
Dec. 31, 2010
Schedule Of Identifiable Intangible Assets Acquired As Part Of Business Combination [Line Items]    
Indefinite-Lived Intangible Assets $ 701 $ 739
Trade names and trademarks [Member]
   
Schedule Of Identifiable Intangible Assets Acquired As Part Of Business Combination [Line Items]    
Indefinite-Lived Intangible Assets 494 494
Refinery air and operating permits [Member]
   
Schedule Of Identifiable Intangible Assets Acquired As Part Of Business Combination [Line Items]    
Indefinite-Lived Intangible Assets $ 207 $ 245