Segment Information (Details) $ in Millions				3 Months Ended				6 Months Ended
	Jun. 24, 2020 USD ($)	Jan. 31, 2020 USD ($)	Oct. 25, 2019 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment								3
Net sales				$ 3,819		$ 3,511		$ 7,667	$ 7,447
Other items				(7)		(6)		2	(8)
Restructuring and impairment costs				(5)		(52)		(12)	(54)
Purchase accounting amortization				(10)		(11)		(21)	(21)
Restructuring related charges				(2)		(7)		(6)	(12)
Loss on business divestiture - net				0		0		0	(25)
Gain on sale / (impairment) of nonconsolidated partially-owned affiliates				33		0		33	(216)
Depreciation				(69)		(72)		(139)	(147)
Stock based compensation				(13)		3		(26)	(1)
Earnings (loss) before interest and income taxes				230		66		512	24
Net financing charges				(110)		(50)		(169)	(98)
Other pension income (expense)				2		2		4	4
Income (loss) before income taxes				122		18		347	(70)
Non-cash impairment charges					$ 6			10	0
Loss on business divestiture - net				0		0		0	(25)
Loss on business divestitures - net				0		0		0	25
Gain on sale of joint venture				33				33	(216)
Integration-related costs				7		6		11	7
China
Segment Reporting Information [Line Items]
Net sales				165		82		354	242
BRAZIL
Segment Reporting Information [Line Items]
One-time tax gain								8
YFAI
Segment Reporting Information [Line Items]
Non-cash impairment charges	$ 9	$ 216					$ 216
One-time tax gain									(1)
Adient Aerospace
Segment Reporting Information [Line Items]
Loss on business divestiture - net									4
Loss on business divestiture - net									4
YFAS
Segment Reporting Information [Line Items]
Gain on previously held interest								5
Americas | Adient Aerospace
Segment Reporting Information [Line Items]
Loss on business divestiture - net			$ 4
Loss on business divestiture - net			$ 4
Americas | RECARO
Segment Reporting Information [Line Items]
Loss on business divestitures - net									21
EMEA
Segment Reporting Information [Line Items]
Non-cash impairment charges				2				8
Operating segments | Americas
Segment Reporting Information [Line Items]
Net sales				1,644		1,641		3,381	3,500
Adjusted EBITDA				64		106		196	200
Operating segments | EMEA
Segment Reporting Information [Line Items]
Net sales				1,636		1,488		3,240	3,052
Adjusted EBITDA				141		62		255	111
Operating segments | Asia
Segment Reporting Information [Line Items]
Net sales				588		444		1,142	1,016
Adjusted EBITDA				121		63		272	240
Elimination
Segment Reporting Information [Line Items]
Net sales				(49)		(62)		(96)	(121)
Corporate-related costs
Segment Reporting Information [Line Items]
Other items				$ (23)		$ (20)		$ (42)	$ (43)