Fair Value of Financial Instruments (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Carrying Value
Financial Assets (Liabilities)
Trading securities	$ 331	$ 308
Available-for-sale securities	5	2
Derivatives	1	(2)
Long-term debt, including current portion	(5,928)	(5,930)
Fair Value
Financial Assets (Liabilities)
Trading securities	331	308
Available-for-sale securities	5	2
Derivatives	1	(2)
Long-term debt, including current portion	$ (6,726)	$ (6,227)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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