Business Segment Information - Sales and Operating Results (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Sales and operating results of reportable segments
Sales	$ 2,052.1	$ 1,981.0
Purchase accounting depreciation and amortization	(35.6)	(26.0)
Corporate and other	(40.0)	(27.3)
Non-operating pension and postretirement benefit credit	4.9	12.4
Change in fair value of investments	3.1	140.6
Interest expense, net	(28.3)	(32.8)
Income before income taxes	259.6	467.9
Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	355.5	401.0
Intelligent Devices
Sales and operating results of reportable segments
Sales	927.3	936.2
Intelligent Devices \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	150.2	209.4
Software & Control
Sales and operating results of reportable segments
Sales	603.6	573.3
Software & Control \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	151.0	167.3
Lifecycle Services
Sales and operating results of reportable segments
Sales	521.2	471.5
Lifecycle Services \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	$ 54.3	$ 24.3

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

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General Corporate - Net

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Non-operating pension costs consist of defined benefit plan interest cost, expected return on plan assets, amortization of actuarial gains and losses and the impacts of any plan curtailments or settlements. These costs are excluded from segment operating earnings.

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Purchase accounting depreciation and amortization that is not allocated to the segments for the purposes of determining segment operating earnings.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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