XML 81 R111.htm IDEA: XBRL DOCUMENT v2.4.0.6
Fair Value Of Financial Assets And Liabilities (Additional Fair Value Disclosure) (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Book Value [Member]
   
Long-term debt, including current maturities $ 20,573 $ 18,210
Fair Value [Member]
   
Long-term debt, including current maturities 23,053 19,484
Variable Interest Entity [Member]
   
Debt of variable interest entities $ 949 $ 976