Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 11	$ (196)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	16	76
Realized and unrealized gains (losses) on derivatives	(3)	(10)
Other comprehensive income (loss)	13	66
Total comprehensive income (loss)	24	(130)
Comprehensive income (loss) attributable to noncontrolling interests	28	25
Comprehensive income (loss) attributable to Adient	$ (4)	$ (155)