Consolidated Statement of Shareowners' Equity Consolidated Statement of Shareowners' Equity - USD ($) $ in Millions		Total	Total attributable to Rockwell Automation, Inc.	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive loss	Common stock in treasury, at cost	Noncontrolling interests
Balance at beginning of period at Sep. 30, 2018		$ 1,617.5	$ 1,617.5	$ 181.4	$ 1,681.4	$ 6,198.1	$ (941.9)	$ (5,501.5)	$ 0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		426.3	426.3			426.3
Other comprehensive income (loss)		1.6	1.6				1.6
Common stock issued (including share-based compensation impact)		46.1	46.1		5.3			40.8
Share repurchases		(528.8)	(528.8)					(528.8)
Cash dividends declared	[1]	(232.5)	(232.5)			(232.5)
Balance at end of period at Mar. 31, 2019		1,336.3	1,336.3	181.4	1,686.7	6,398.0	(940.3)	(5,989.5)	0.0
Balance at beginning of period at Dec. 31, 2018		1,274.3	1,274.3	181.4	1,674.4	6,167.6	(976.9)	(5,772.2)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		346.0	346.0			346.0
Other comprehensive income (loss)		36.6	36.6				36.6
Common stock issued (including share-based compensation impact)		31.0	31.0		12.3			18.7
Share repurchases		(236.0)	(236.0)					(236.0)
Cash dividends declared	[2]	(115.6)	(115.6)			(115.6)
Balance at end of period at Mar. 31, 2019		1,336.3	1,336.3	181.4	1,686.7	6,398.0	(940.3)	(5,989.5)	0.0
Balance at beginning of period at Sep. 30, 2019		404.2	404.2	181.4	1,709.1	6,440.2	(1,488.0)	(6,438.5)	0.0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		445.3	442.9			442.9			2.4
Other comprehensive income (loss)		4.6	5.2				5.2		(0.6)
Common stock issued (including share-based compensation impact)		156.2	156.2		33.1			123.1
Share repurchases		(206.4)	(206.4)					(206.4)
Cash dividends declared		(236.3)	(236.3)			(236.3)
Change in noncontrolling interest		368.1	52.8	0.0	49.0	0.0	3.8	0.0	315.3
Balance at end of period at Mar. 31, 2020		937.9	620.8	181.4	1,791.2	6,795.8	(1,625.8)	(6,521.8)	317.1
Balance at beginning of period at Dec. 31, 2019		1,036.5	717.0	181.4	1,775.5	6,782.0	(1,584.3)	(6,437.6)	319.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income		129.9	132.2			132.2			(2.3)
Other comprehensive income (loss)		(42.4)	(41.5)				(41.5)		(0.9)
Common stock issued (including share-based compensation impact)		38.8	38.8		16.8			22.0
Share repurchases		(106.2)	(106.2)					(106.2)
Cash dividends declared	[2]	(118.4)	(118.4)			(118.4)
Change in noncontrolling interest		(0.3)	(1.1)		(1.1)				0.8
Balance at end of period at Mar. 31, 2020		$ 937.9	$ 620.8	$ 181.4	$ 1,791.2	$ 6,795.8	$ (1,625.8)	$ (6,521.8)	$ 317.1

[1] Cash dividends were $2.04 per share and $1.94 per share in the six months ended March 31, 2020 and 2019, respectively.

[2] Cash dividends were $1.02 per share and $0.97 per share in the three months ended March 31, 2020 and 2019, respectively.