|
Marketable Securities, at Fair Value (Schedule of Available-for-sale Securities) (Details) (Investments [Member], USD $)
In Millions, unless otherwise specified |
Sep. 30, 2014
|
Dec. 31, 2013
|
|---|---|---|
|
Investments [Member]
|
||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized cost | $ 36 | $ 41 |
| Gross unrealized gain | 0 | 0 |
| Gross unrealized loss | 0 | 0 |
| Fair value | $ 36 | $ 41 |