Debt - Summary of Short-Term Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016
Short-term Debt [Line Items]
Other Short-term Borrowings	$ 3	$ 1
Short-term debt	203	1,001
Commercial paper borrowings
Short-term Debt [Line Items]
Commercial paper borrowings	$ 0	200
4.900% Notes due April 15, 2018
Short-term Debt [Line Items]
Interest rate	4.90%
Current portion of long-term debt	$ 200	0
1.450% Notes due May 15, 2017
Short-term Debt [Line Items]
Interest rate	1.45%
Current portion of long-term debt	$ 0	300
Notes Due 2016
Short-term Debt [Line Items]
Interest rate	1.75%
Current portion of long-term debt	$ 0	$ 500

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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