Goodwill and Purchased Intangible Assets - Amorization Expense (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 30
Amortization expense for remainder of the fiscal year	11
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2013	42
2014	40
2015	39
2016	34
2017	$ 25

Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months

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- Definition

Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year

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- Definition

Finite-Lived Intangible Assets, Amortization Expense, Year Five

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- Definition

Finite-Lived Intangible Assets, Amortization Expense, Year Four

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Finite-Lived Intangible Assets, Amortization Expense, Year Three

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Finite-Lived Intangible Assets, Amortization Expense, Year Two

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- Definition

Aggregate amount of intangible asset amortization recognized as expense during the period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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