Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (49)	$ (331)	$ 218	$ (471)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	25	17	62	(65)
Realized and unrealized gains (losses) on derivatives	17	24	34	(23)
Other comprehensive income (loss)	42	41	96	(88)
Total comprehensive income (loss)	(7)	(290)	314	(559)
Comprehensive income (loss) attributable to noncontrolling interests	23	3	79	41
Comprehensive income (loss) attributable to Adient	$ (30)	$ (293)	$ 235	$ (600)