Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Intangible assets with definite lives
Gross Carrying Amount	$ 79	$ 79
Accumulated Amortization	(63)	(61)
Net	16us-gaap_FiniteLivedIntangibleAssetsNet	18us-gaap_FiniteLivedIntangibleAssetsNet
Customer relationships
Intangible assets with definite lives
Gross Carrying Amount	70	70
Accumulated Amortization	(56)	(54)
Net	14	16
Other
Intangible assets with definite lives
Gross Carrying Amount	9	9
Accumulated Amortization	(7)	(7)
Net	$ 2	$ 2

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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