Defined benefit plan target allocation percentage plan assets.

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

+ Details

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- Definition

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.

+ Details

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of cost (reversal of cost) for other postretirement benefits. Excludes pension benefits.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plans expenses		$ 15	$ 18	$ 19
Pension Benefits [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution	$ 4
Postretirement Benefits [Member] \| Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement medical benefits	$ 3
U.S. Defined Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		2	3
Foreign Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 125	$ 209
Foreign Plans [Member] \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		18.00%
Foreign Plans [Member] \| Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		67.00%
Foreign Plans [Member] \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		11.00%
Foreign Plans [Member] \| Cash and Other Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		4.00%