Stock-Based Compensation - Restricted Stock (Details) - Restricted Stock	12 Months Ended
Sep. 30, 2019 $ / shares shares
Weighted Average Price
Nonvested shares, weighted average grant date fair value at beginning period (in dollars per share) \| $ / shares	$ 48.62
Nonvested shares granted, weighted average grant date fair value (in dollars per share) \| $ / shares	34.26
Nonvested shares vested, weighted average grant date fair value (in dollars per share) \| $ / shares	46.14
Nonvested shares forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	48.92
Nonvested shares, weighted average grant date fair value at ending period (in dollars per share) \| $ / shares	$ 42.19
Shares/Units Subject to Restriction
Nonvested shares at beginning period (in shares) \| shares	1,442,011
Nonvested shares granted (in shares) \| shares	440,944
Nonvested shares vested (in shares) \| shares	(1,045,336)
Nonvested shares forfeited (in shares) \| shares	(278,687)
Nonvested shares at ending period (in shares) \| shares	558,932
Former Parent Plan
Weighted Average Price
Nonvested shares, weighted average grant date fair value at ending period (in dollars per share) \| $ / shares	$ 0
Shares/Units Subject to Restriction
Nonvested shares at ending period (in shares) \| shares	0
Adient Plan
Weighted Average Price
Nonvested shares, weighted average grant date fair value at ending period (in dollars per share) \| $ / shares	$ 42.19
Shares/Units Subject to Restriction
Nonvested shares at ending period (in shares) \| shares	558,932

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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-Publisher FASB
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