Financial Instruments (Details) - USD ($) $ in Millions	Jun. 30, 2015	Sep. 30, 2014
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	$ 345	$ 247
Short-term debt	18	7
Long-term debt	1,079	965
Carrying Value \| Foreign exchange forward contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign exchange forward contracts (asset)	2	2
Carrying Value \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term foreign currency option contracts (asset)	0	2
Long-term foreign currency option contracts (asset)	1	1
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	345	247
Short-term debt	18	7
Long-term debt	1,217	1,143
Fair Value \| Foreign exchange forward contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Foreign exchange forward contracts (asset)	2	2
Fair Value \| Foreign currency option contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term foreign currency option contracts (asset)	0	2
Long-term foreign currency option contracts (asset)	$ 1	$ 1

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

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-Publisher FASB

-Name Accounting Standards Codification

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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