Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 4,276	$ 804	$ 5,233	$ 1,558
Other comprehensive income (loss), net of tax
Foreign currency translation adjustments	(94)	(614)	(95)	(331)
Realized and unrealized gains (losses) on derivatives	(9)	1	10	(10)
Realized and unrealized losses on marketable securities	0	0	0	(2)
Other comprehensive loss	(103)	(613)	(85)	(343)
Total comprehensive income	4,173	191	5,148	1,215
Comprehensive income attributable to noncontrolling interests	76	22	179	159
Comprehensive income attributable to Johnson Controls	$ 4,097	$ 169	$ 4,969	$ 1,056

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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