Fair Value of Financial Instruments (Unaudited) #1 (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Marketable Securities
Trading securities, carrying value	$ 249	$ 219
Trading securities, fair value	249	219
Available-for-sale securities, carrying value	3	4
Available-for-sale securities, fair value	3	4
Held-to-Maturity time deposits, carrying value	0	250
Held-to-Maturity time deposits, fair value	0	250
Derivative assets, carrying value	1	7
Derivative assets, fair value	1	7
Long-term debt, including current portion, carrying value	(3,936)	(3,940)
Long-term debt, including current portion, fair value	$ (4,902)	$ (4,675)

Derivative assets carrying value.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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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