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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

No definition available.

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Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($)		3 Months Ended						6 Months Ended	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Mar. 12, 2021
Goodwill [Line Items]
Impairment									$ 0
Intangible asset gross	$ 785,000,000	$ 785,000,000		$ 602,000,000					785,000,000	$ 602,000,000
Long-lived asset impairment charges			$ 9,000,000		$ 6,000,000		$ 66,000,000
Amortization of intangibles									45,000,000	37,000,000	$ 40,000,000
Anticipated amortization expense, 2022	54,000,000	54,000,000							54,000,000
Anticipated amortization expense, 2023	53,000,000	53,000,000							53,000,000
Anticipated amortization expense, 2024	51,000,000	51,000,000							51,000,000
Anticipated amortization expense, 2025	49,000,000	49,000,000							49,000,000
Anticipated amortization expense, 2026	48,000,000	48,000,000							$ 48,000,000
Yanfeng Adient Seating Co., Ltd. (YFAS)
Goodwill [Line Items]
Intangible asset gross				92,000,000						92,000,000	$ 92,000,000	$ 92,000,000
Finite-lived intangible assets, remaining amortization period									18 years		18 years
Impairment of definite-lived intangible assets		$ 86,000,000
Valuation, Income Approach \| Measurement Input, Cap Rate \| Significant Unobservable Inputs (Level 3) \| Yanfeng Adient Seating Co., Ltd. (YFAS)
Goodwill [Line Items]
Reporting unit, measurement input		10.50%
Customer relationships
Goodwill [Line Items]
Finite lived intangible assets acquired	176,000,000
Intangible asset gross	649,000,000	$ 649,000,000		424,000,000					$ 649,000,000	424,000,000
Impairment of definite-lived intangible assets							$ 4,000,000
Patented technology
Goodwill [Line Items]
Finite lived intangible assets acquired	60,000,000
Intangible asset gross	$ 86,000,000	$ 86,000,000		27,000,000					$ 86,000,000	$ 27,000,000
Asia
Goodwill [Line Items]
Long-lived asset impairment charges					27,000,000
Asia \| China
Goodwill [Line Items]
Long-lived asset impairment charges				$ 5,000,000
Asia \| Customer relationship intangible assets
Goodwill [Line Items]
Long-lived asset impairment charges					24,000,000
Asia \| Noncurrent assets \| China
Goodwill [Line Items]
Long-lived asset impairment charges					$ 3,000,000
Minimum \| Valuation, Income Approach \| Measurement Input, Cap Rate \| Significant Unobservable Inputs (Level 3)
Goodwill [Line Items]
Reporting unit, measurement input				16.00%		15.00%		15.00%
Maximum \| Valuation, Income Approach \| Measurement Input, Cap Rate \| Significant Unobservable Inputs (Level 3)
Goodwill [Line Items]
Reporting unit, measurement input				18.50%		17.50%		17.50%