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Variable Interest Entity, Number Of Entities

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No definition available.

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- Definition

Carrying value of securities sold under agreements to repurchase and deposits received for securities loaned.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
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- Definition

Carrying amount as of the balance sheet date of capitalized costs of molds, dies, and other tools that the entity does not own which are or will be used in producing goods under a long-term supply arrangement, and for which there is a noncancelable right of use during such arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 340
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- Definition

Carrying amount as of the balance sheet date of capitalized costs of molds, dies, and other tools that will be used in producing products under a long-term supply arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The carrying amount as of the balance sheet date of capitalized preproduction costs incurred on long-term supply arrangements, including recoverable costs to design and develop products.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 340
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

Amount of expense for research and development. Includes, but is not limited to, cost for computer software product to be sold, leased, or otherwise marketed and writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both. Excludes write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 220
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Organization and Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	12 Months Ended
	Sep. 30, 2025 USD ($) entity	Sep. 30, 2024 USD ($) entity	Sep. 30, 2023 USD ($)
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Number of VIE entities \| entity	2	2
Amount funded under accounts receivable repurchase program	$ 185	$ 170
Engineering, research and development, and other design and development costs	365	310
Research and development costs	387	372	$ 362
Research and development costs reimbursed by customers	288	280	250
Foreign currency translation gain (loss)	$ (8)	$ (3)	$ 4
Ford Motor Company \| Net sales \| Customer concentration risk
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Concentration risk (as percent)	11.00%	12.00%	11.00%
Volkswagen Group \| Net sales \| Customer concentration risk
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Concentration risk (as percent)	10.00%	13.00%	11.00%
Stellantis N.V. \| Net sales \| Customer concentration risk
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Concentration risk (as percent)	10.00%		10.00%
Minimum \| Buildings and improvements
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Useful life	3 years
Minimum \| Machinery and equipment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Useful life	3 years
Maximum \| Buildings and improvements
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Useful life	40 years
Maximum \| Machinery and equipment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Useful life	15 years
Current assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Engineering, research and development, and other design and development costs	$ 136	$ 108
Costs for molds, dies and other tools to be reimbursed by customer	237	156
Other noncurrent assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Engineering, research and development, and other design and development costs	229	202
Costs for molds, dies and other tools to be reimbursed by customer	18	25
Property, plant and equipment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Costs for molds, dies and other tools with title	$ 41	$ 50