Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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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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Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 2,150	$ 2,150	$ 2,182
Currency translation and other			8	(32)
Loss on business divestitures - net			(13)	0	$ 0
Goodwill, ending balance			2,057	2,150	2,182
RECARO
Goodwill [Roll Forward]
Loss on business divestitures - net		(21)	(101)
Americas Segment
Goodwill [Roll Forward]
Goodwill, beginning balance		638	638	642
Currency translation and other			(11)	(4)
Goodwill, ending balance			606	638	642
Americas Segment \| RECARO
Goodwill [Roll Forward]
Loss on business divestitures - net	$ (21)		(21)
EMEA Segment
Goodwill [Roll Forward]
Goodwill, beginning balance		429	429	469
Currency translation and other			19	(40)
Goodwill, ending balance			368	429	469
EMEA Segment \| RECARO
Goodwill [Roll Forward]
Loss on business divestitures - net			(80)
Asia Segment
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 1,083	1,083	1,071
Currency translation and other			0	12
Goodwill, ending balance			1,083	$ 1,083	$ 1,071
Asia Segment \| RECARO
Goodwill [Roll Forward]
Loss on business divestitures - net			$ 0