Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 156	$ 419
Other comprehensive income, net of tax:
Foreign currency translation adjustments	90	86
Realized and unrealized gains (losses) on derivatives	(17)	7
Pension and postretirement plans	(1)	(1)
Other comprehensive income	72	92
Total comprehensive income	228	511
Comprehensive income attributable to noncontrolling interests:
Income attributable to noncontrolling interests	38	38
Other comprehensive income, net of tax:
Foreign currency translation adjustments	31	2
Realized and unrealized gains (losses) on derivatives	(6)	3
Other comprehensive income	25	5
Comprehensive income attributable to noncontrolling interests	63	43
Comprehensive income attributable to Johnson Controls	$ 165	$ 468