Financial Instruments, Derivatives and Hedging Activities (Details 4) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Fair value of assets and liabilities
Long-term debt	$ 2,360
Fair Value, Measurements, Recurring \| Level 1
Fair value of assets and liabilities
Available for sale securities	6	$ 5
Derivative assets	7	12
Derivative liabilities	3	6
Fair Value, Measurements, Recurring \| Level 2
Fair value of assets and liabilities
Derivative assets	32	17
Derivative liabilities	11	17
Long-term debt	2,356	1,939
Fair Value, Measurements, Recurring \| Total
Fair value of assets and liabilities
Available for sale securities	6	5
Derivative assets	39	29
Derivative liabilities	14	23
Long-term debt	$ 2,356	$ 1,939

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

-Topic 320

-SubTopic 10

-Section 25

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

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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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