|
Short-Term Investments Components Of Short-Term Investments (Components Of Short-Term Investments) (Details) (USD $)
In Millions, unless otherwise specified |
12 Months Ended | |
|---|---|---|
|
Dec. 31, 2011
days
|
Dec. 31, 2010
|
|
| Schedule of Investments [Line Items] | ||
| Average remaining maturity on short-term investments | 75 | |
| Average yield on short-term investments | 0.28% | |
| Short-term investments | $ 1,503 | $ 145 |
|
Other [Member]
|
||
| Schedule of Investments [Line Items] | ||
| Short-term investments | 289 | |
|
Commercial Paper [Member]
|
||
| Schedule of Investments [Line Items] | ||
| Short-term investments | 1,013 | |
|
U.S. Treasuries [Member]
|
||
| Schedule of Investments [Line Items] | ||
| Short-term investments | $ 201 | $ 145 |