Quarterly report pursuant to Section 13 or 15(d)

Financial Instruments (Details)

v2.4.0.8
Financial Instruments (Details) (Recurring, Level 2 market data, USD $)
In Billions, unless otherwise specified
Sep. 30, 2013
Dec. 31, 2012
Recurring | Level 2 market data
   
Financial Instruments    
Fair value of senior notes $ 1.5 $ 1.3