Fair Value of Financial Instruments (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Marketable Securities
Held-to-Maturity time deposits, Carrying value	$ 250
Fair Value Measurements Recurring [Member]
Marketable Securities
Trading securities, carrying value	219	320
Trading securities, fair Value	219	320
Available-for-Sale, carrying value	4	10
Available-for-sale Securities, fair Value	4	10
Held-to-Maturity time deposits, Carrying value	250
Held-to-Maturity time deposits, Fair value	250
Derivative assets, carrying value	7	11
Derivatives, fair value	7	11
Long-term debt, including current portion	(3,940)	(4,724)
Long-term debt, including current portion	$ (4,675)	$ (5,100)

Derivative assets carrying value.

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The total of financial instruments that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt and equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition.

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