v2.4.0.6
Fair Value of Financial Assets and Liabilities - Summary of Estimated Fair Value and Carrying Amount of Financial Instruments Measured on Recurring Basis (Detail) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Liabilities:      
Short-term debt $ (307) $ (52)  
Long-term debt (3,185) (3,747) (4,128)
Carrying Amount [Member] | Level II [Member]
      
Assets:      
Other financial assets 18 17  
Derivative instruments-assets 1 2  
Liabilities:      
Short-term debt (42) (52)  
Long-term debt (608) [1] (606) [1]  
Other long-term debt (245) (19)  
Derivative instruments-liabilities (2) (3)  
Carrying Amount [Member] | Level I [Member]
      
Liabilities:      
Short-term debt (265)    
Long-term debt (2,332) (3,122)  
Estimated Fair Value [Member] | Level II [Member]
      
Assets:      
Other financial assets 18 17  
Derivative instruments-assets 1 2  
Liabilities:      
Short-term debt (42) (52)  
Long-term debt (635) [1] (609) [1]  
Other long-term debt (245) (19)  
Derivative instruments-liabilities (2) (3)  
Estimated Fair Value [Member] | Level I [Member]
      
Liabilities:      
Short-term debt (267)    
Long-term debt $ (2,453) $ (3,296)  
[1] Represent bonds which are privately held (floating rate secured notes 2016).