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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
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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.

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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 715
-SubTopic 20
-Section 50
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from settlement and curtailment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 715
-SubTopic 70
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- Definition

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

+ References

No definition available.

+ Details

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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plans expenses		$ 19	$ 18	$ 17
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Net losses on curtailments and settlements		(1)	(1)	$ (1)
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss amortized from AOCI to net periodic benefit cost	$ 3
Amortization of estimated prior service credits	2
Scenario, Forecast [Member] \| Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Postretirement medical benefits	$ 4
U.S. Defined Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 143	160
Weighted-average assumed health care cost trend rate		7.00%
U.S. Defined Benefit Plans [Member] \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		30.00%
U.S. Defined Benefit Plans [Member] \| Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		70.00%
U.S. Defined Benefit Plans [Member] \| Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net losses on curtailments and settlements		$ (5)	(5)
Foreign Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation		$ 349	351
Weighted-average assumed health care cost trend rate		7.10%
Foreign Plans [Member] \| Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		39.00%
Foreign Plans [Member] \| Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		53.00%
Foreign Plans [Member] \| Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		3.00%
Foreign Plans [Member] \| Cash and Other Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of weighted-average target asset allocation		5.00%
Foreign Plans [Member] \| Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contribution		$ 8
Net losses on curtailments and settlements		$ (2)	$ (3)