Fair Values of Assets and Liabilities - Level 3 Rollforward (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assets
Beginning Balance	$ 11	$ 0	$ 2
Total realized and unrealized gains included in earnings	(1)	8	0
Purchases	0	7	0
Settlements	(3)	(4)	(2)
Foreign currency translation	(1)	0	0
Ending Balance	6	11	0
Liabilities
Beginning Balance	(17)	0	(6)
Total realized and unrealized gains included in earnings	(50)	(9)	0
Purchases	0	(19)	0
Settlements	22	11	6
Foreign currency translation	6	0	0
Ending Balance	$ (39)	$ (17)	$ 0

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis, Asset, Foreign Currency Translation

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- Definition

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis, Liabilities, Foreign Currency Translation

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No definition available.

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- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

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-Section 50

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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