Nonconsolidated Partially-Owned Affiliates - Partially-owned Affiliates (Details)	Sep. 30, 2024	Sep. 30, 2023
KEIPER Seating Mechanisms Co., Ltd. (“KEIPER”)
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percent	50.00%	50.00%
Changchun FAWAY Adient Automotive Systems Co. Ltd. (“CFAA”)
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percent	49.00%	49.00%

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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