Fair Value Measurements and Financial Instruments (Details 5) (Bonds Issued By Venezuelan Government [Member], USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Bonds Issued By Venezuelan Government [Member]
   
Venezuelan Investments [Roll Forward]    
Beginning balance $ 399 $ 685
Unrealized gain (loss) on investment (1) (298)
Purchases and sales during the period 33 54
Ending balance $ 431 $ 441