Risk Management Debt Fair Value Adjustments (Details Textrual) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2014	Dec. 31, 2013
Fair Value, Adjustment Disclosure [Abstract]
Increase (decrease) in debt fair value adjustment related to purchase accounting	$ 597	$ 645
Amount the adjustment to fair value of debt was increased by related to the fair value of interest rate swaps	204	101
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	470	517
Amount the fair value of debt adjustment was decreased by related to unamortized debt discounts	$ 59	$ 49
Amortization Period of Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	16 years

Amount the adjustment to fair value of debt was increased by related to the fair value of interest rate swaps

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- Definition

Increase (decrease) in debt fair value adjustment related to purchase accounting

+ References

No definition available.

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- Definition

Period when adjustments to the carrying value of an interest-bearing hedged item are amortized upon discontinuation of the interest rate fair value hedge, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 35

-Paragraph 9

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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective interest rate fair value hedge that is amortized upon discontinuation of the interest rate fair value hedge.

+ References

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