Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (408)	$ (1,601)	$ 962
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(35)	(117)	(133)
Realized and unrealized gains (losses) on derivatives			17
Realized and unrealized gains (losses) on derivatives	(1)	(10)	17
Pension and postretirement plans	(2)	1	0
Other comprehensive income (loss)	(38)	(126)	(116)
Total comprehensive income (loss)	(446)	(1,727)	846
Comprehensive income (loss) attributable to noncontrolling interests	83	92	90
Comprehensive income (loss) attributable to Adient	$ (529)	$ (1,819)	$ 756

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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