Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (126)	$ (143)	$ (115)	$ (339)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	40	142	56	218
Realized and unrealized gains (losses) on derivatives	4	10	1	0
Other comprehensive income (loss)	44	152	57	218
Total comprehensive income (loss)	(82)	9	(58)	(121)
Comprehensive income (loss) attributable to noncontrolling interests	28	35	56	60
Comprehensive income (loss) attributable to Adient	$ (110)	$ (26)	$ (114)	$ (181)