Derivatives and Hedging Interest Rate Management Risk Narrative (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Derivative [Line Items]
Estimated pretax losses currently included within Accumulated Other Comprehensive Loss that will be reclassified to earnings in next twelve months	$ 4
Derivative gain (loss)	(1)	(23)
Not Designated as Hedging Instrument [Member] \| Foreign exchange contracts [Member]
Derivative [Line Items]
Derivative gain (loss)	$ 7	$ (5)
Cash Flow Hedging [Member]
Derivative [Line Items]
Interest rate fluctuations, maximum hedging period	2 years

Represents the estimated net amount of unrealized gains (losses) on hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (a),(c),(d),(e)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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- Definition

Maximum period the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, 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 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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- Details

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