Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 2,150
Gain (Loss) on Disposition of Business	(25)	$ 0
Currency translation and other	28
Goodwill, ending balance	2,157
RECARO
Goodwill [Roll Forward]
Gain (Loss) on Disposition of Business	(21)
Americas
Goodwill [Roll Forward]
Goodwill, beginning balance	638
Currency translation and other	1
Goodwill, ending balance	618
Americas \| RECARO
Goodwill [Roll Forward]
Gain (Loss) on Disposition of Business	(21)
EMEA
Goodwill [Roll Forward]
Goodwill, beginning balance	429
Currency translation and other	13
Goodwill, ending balance	442
EMEA \| RECARO
Goodwill [Roll Forward]
Gain (Loss) on Disposition of Business	0
Asia
Goodwill [Roll Forward]
Goodwill, beginning balance	1,083
Currency translation and other	14
Goodwill, ending balance	1,097
Asia \| RECARO
Goodwill [Roll Forward]
Gain (Loss) on Disposition of Business	$ 0

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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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.

+ References

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