Business Segment Information - Schedule of Reportable Segments (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Sales	$ 7,760.4	$ 6,997.4	$ 6,329.8
Sales and operating results of reportable segments
Purchase accounting depreciation and amortization	(103.9)	(55.1)	(41.4)
Corporate and other	(104.7)	(120.6)	(98.9)
Non-operating pension and postretirement benefit cost	(4.7)	(63.8)	(37.4)
Change in fair value of investments	(136.9)	397.4	153.9
Legal settlement	0.0	70.0	0.0
Interest expense, net	(118.8)	(93.0)	(98.0)
Income before income taxes	1,073.6	1,526.2	1,136.1
Operating Segments
Segment Reporting Information [Line Items]
Sales	7,760.4	6,997.4	6,329.8
Segment operating earnings	1,542.6	1,391.3	1,257.9
Intelligent Devices
Segment Reporting Information [Line Items]
Sales	3,544.6	3,311.9
Intelligent Devices \| Operating Segments
Segment Reporting Information [Line Items]
Sales	3,544.6	3,311.9	2,956.0
Segment operating earnings	717.6	702.1	587.8
Software & Control
Segment Reporting Information [Line Items]
Sales	2,312.9	1,947.0
Software & Control \| Operating Segments
Segment Reporting Information [Line Items]
Sales	2,312.9	1,947.0	1,681.3
Segment operating earnings	666.7	531.0	473.8
Lifecycle Services \| Operating Segments
Segment Reporting Information [Line Items]
Sales	1,902.9	1,738.5	1,692.5
Segment operating earnings	$ 158.3	$ 158.2	$ 196.3

Equity Securities, FV-NI, Unrealized Gain (Loss), Loss On Investment

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