|
Disclosure Of Fair Value Of Financial Instruments (Details) (USD $)
In Billions |
Jun. 30, 2011
|
Dec. 31, 2010
|
|---|---|---|
| Disclosure Of Fair Value Of Financial Instruments | Â | Â |
| Fair value of company's long-term debt | $ 2.0 | $ 2.2 |
| Book value of company's long-term debt | $ 1.9 | $ 2.1 |