Goodwill and Purchased Intangible Assets - Schedule of Acquired Intangibles (Details) (USD $) In Millions, unless otherwise specified											6 Months Ended
Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 Reseller & customer relationships [Member]	Dec. 31, 2012 Reseller & customer relationships [Member]	Jun. 30, 2013 Intellectual property [Member]	Dec. 31, 2012 Intellectual property [Member]	Jun. 30, 2013 Tradenames [Member]	Dec. 31, 2012 Tradenames [Member]	Jun. 30, 2013 Non-compete arrangements [Member]	Dec. 31, 2012 Non-compete arrangements [Member]	Jun. 30, 2013 Minimum [Member] Reseller & customer relationships [Member]	Jun. 30, 2013 Minimum [Member] Intellectual property [Member]	Jun. 30, 2013 Minimum [Member] Tradenames [Member]	Jun. 30, 2013 Minimum [Member] Non-compete arrangements [Member]	Jun. 30, 2013 Maximum [Member] Reseller & customer relationships [Member]	Jun. 30, 2013 Maximum [Member] Intellectual property [Member]	Jun. 30, 2013 Maximum [Member] Tradenames [Member]	Jun. 30, 2013 Maximum [Member] Non-compete arrangements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization period (in years)											1 year	2 years	4 years	2 years	20 years	7 years	9 years	5 years
Accumulated Amortization	$ (143)	$ (112)	$ (27)	$ (17)	$ (98)	$ (80)	$ (11)	$ (8)	$ (7)	$ (7)
Finite-Lived Intangible Assets, Gross	$ 633	$ 416	$ 311	$ 179	$ 255	$ 180	$ 59	$ 49	$ 8	$ 8

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, 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 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

+ Details

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- Definition

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

+ Details

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- Definition

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

+ References

+ Details

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