Fair Value of Financial Instruments (Details 1) (Fair Value Measurements Recurring (Table Values) [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Fair Value Measurements Recurring (Table Values) [Member]
Marketable Securities
Trading securities, carrying value	$ 259	$ 219
Trading securities, fair value	259	219
Available-for-sale, carrying value	3	4
Available-for-sale, fair value	3	4
Held-to-Maturity time deposits, carrying value	0	250
Held-to-Maturity time deposits, fair value	0	250
Derivatives, carrying value	(1)	7
Derivatives, fair value	(1)	7
Long-term debt, including current portion, carrying value	(3,935)	(3,940)
Long-term debt, including current portion, fair value	$ (4,834)	$ (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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