Segment Information (Details) $ in Millions	3 Months Ended
	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	3
Total	$ 4,158	$ 4,204
Becoming Adient costs	0	(19)
Restructuring and impairment costs	(31)	0
Purchase accounting amortization	(10)	(17)
Restructuring related charges	(9)	(11)
Stock based compensation	(6)	(10)
Depreciation	(65)	(94)
Other items	(1)	(14)
Earnings (loss) before interest and income taxes	54	101
Net financing charges	(35)	(33)
Other pension income	2	1
Income (loss) before income taxes	21	69
Becoming Adient non-cash costs		6
Depreciation	65	96
Income tax provision	10	265
YFAI
Segment Reporting Information [Line Items]
Income tax provision		8
Futuris
Segment Reporting Information [Line Items]
Integration-related costs	1	6
Becoming Adient Costs
Segment Reporting Information [Line Items]
Stock based compensation		(6)
Depreciation		2
Seating
Segment Reporting Information [Line Items]
Total	3,738	3,795
SS&M
Segment Reporting Information [Line Items]
Total	420	409
Operating segments
Segment Reporting Information [Line Items]
Total	4,466	4,514
Operating segments | Seating
Segment Reporting Information [Line Items]
Total	3,739	3,796
Adjusted EBITDA	261	354
Operating segments | SS&M
Segment Reporting Information [Line Items]
Total	727	718
Adjusted EBITDA	(72)	(82)
Operating segments | Interiors
Segment Reporting Information [Line Items]
Adjusted EBITDA	11	25
Eliminations
Segment Reporting Information [Line Items]
Total	(308)	(310)
Eliminations | Seating
Segment Reporting Information [Line Items]
Total	(1)	(1)
Eliminations | SS&M
Segment Reporting Information [Line Items]
Total	(307)	(309)
Corporate-related costs
Segment Reporting Information [Line Items]
Other items	$ (24)	$ (31)