Business Segment Information - Sales and Operating Results (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Sales and operating results of reportable segments
Sales	$ 1,981.0	$ 1,857.3
Purchase accounting depreciation and amortization	(26.0)	(26.1)
Corporate and other	(27.3)	(29.4)
Non-operating pension and postretirement benefit credit	12.4	4.4
Change in fair value of investments	140.6	7.6
Interest expense, net	(32.8)	(29.1)
Income before income taxes	467.9	282.5
Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	401.0	355.1
Intelligent Devices
Sales and operating results of reportable segments
Sales	936.2	900.3
Intelligent Devices \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	209.4	213.0
Software & Control
Sales and operating results of reportable segments
Sales	573.3	513.9
Software & Control \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	167.3	117.6
Lifecycle Services
Sales and operating results of reportable segments
Sales	471.5	443.1
Lifecycle Services \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	$ 24.3	$ 24.5

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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Amount of interest revenue (income derived from investments in debt securities and on cash and cash equivalents) net of interest expense (cost of borrowed funds accounted for as interest).

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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