Goodwill and Purchased Intangible Assets - Schedule of Acquired Intangibles (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,223	$ 1,224
Accumulated Amortization	(330)	(298)
Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	660	660
Accumulated Amortization	(71)	(63)
Intellectual property [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	392	393
Accumulated Amortization	(197)	(181)
Customer Contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	8 years
Finite-Lived Intangible Assets, Gross	89	89
Accumulated Amortization	(28)	(22)
Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	74	74
Accumulated Amortization	(26)	(24)
Non-compete arrangements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	8	8
Accumulated Amortization	$ (8)	$ (8)
Minimum [Member] \| Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	1 year
Minimum [Member] \| Intellectual property [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Minimum [Member] \| Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Minimum [Member] \| Non-compete arrangements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years
Maximum [Member] \| Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Maximum [Member] \| Intellectual property [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	8 years
Maximum [Member] \| Tradenames [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Maximum [Member] \| Non-compete arrangements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years

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

+ References

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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- Definition

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

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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