Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	$ 314	$ 323
Gross Carrying Value	371	380
Accumulated Amortization	(36)	(33)
Net Intangible Assets, finite lives	278us-gaap_FiniteLivedIntangibleAssetsNet	290us-gaap_FiniteLivedIntangibleAssetsNet
Net Intangible Assets	335	347
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	150	152
Accumulated Amortization	(18)	(16)
Net Intangible Assets, finite lives	132	136
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value, finite lives	164	171
Accumulated Amortization	(18)	(17)
Net Intangible Assets, finite lives	146	154
Trademarks, Indefinite Lives [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value, Trademarks, indefinite lives	57	57
Net Intangible Assets, Trademarks, indefinite lives	$ 57	$ 57

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)

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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 of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

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