v2.4.0.6
Supplemental Financial Information (Cash Payments for Interest and Income Taxes)(Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 12 Months Ended
Mar. 31, 2013
Dec. 31, 2012
Supplemental Financial Information [Abstract]    
Interest $ 617 $ 614
Income taxes $ 461 $ 118