Consolidated Statements of Shareholders' Equity Attributable to Johnson Controls Ordinary Shareholders - USD ($) $ in Millions	Total	Ordinary Shares	Capital in excess of par value	Retained Earnings	Treasury Stock, at Cost	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Sep. 30, 2015	$ 10,335	$ 7	$ 3,740	$ 10,797	$ (3,152)	$ (1,057)
Comprehensive income (loss) attributable to Johnson Controls	(964)	0	0	(868)	0	(96)
Result of contribution of Johnson Controls, Inc. to Johnson Controls International plc	15,808	2	12,157	0	3,649	0
Cash dividends	(752)	0	0	(752)	0	0
Repurchases of common stock	(501)	0	0	0	(501)	0
Other, including options exercised	192	0	208	0	(16)	0
Ending balance at Sep. 30, 2016	24,118	9	16,105	9,177	(20)	(1,153)
Comprehensive income (loss) attributable to Johnson Controls	1,710	0	0	1,611	0	99
Cash dividends	(938)	0	0	(938)	0	0
Repurchases of common stock	(651)	0	0	0	651	0
Stockholder's equity, spin-off of Adient	(4,038)	0	0	(4,619)	0	581
Other, including options exercised	246	0	285	0	(39)	0
Ending balance at Sep. 30, 2017	20,447	9	16,390	5,231	(710)	(473)
Comprehensive income (loss) attributable to Johnson Controls	1,689	0	0	2,162	0	(473)
Cash dividends	(968)	0	0	(968)	0	0
Repurchases of common stock	(300)	0	0	0	(300)	0
Adoption of ASU 2016-09	179	0	0	179	0	0
Other, including options exercised	117	(1)	159	0	(43)	0
Ending balance at Sep. 30, 2018	$ 21,164	$ 10	$ 16,549	$ 6,604	$ (1,053)	$ (946)