Business Segment Information - Sales and Operating Results (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Sales and operating results of reportable segments
Sales	$ 2,001.0	$ 2,126.0	$ 3,882.0	$ 4,178.0
Purchase accounting depreciation and amortization	(36.0)	(37.0)	(71.0)	(73.0)
Corporate and other	(33.0)	(28.0)	(71.0)	(68.0)
Non-operating pension and postretirement benefit credit	0.0	5.0	0.0	10.0
Change in fair value of investments	(3.0)	3.0	(3.0)	6.0
Interest expense, net	(37.0)	(37.0)	(72.0)	(65.0)
Income before income taxes	299.0	310.0	512.0	570.0
Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	408.0	404.0	729.0	760.0
Intelligent Devices
Sales and operating results of reportable segments
Sales	896.0	974.0	1,702.0	1,901.0
Intelligent Devices \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	159.0	161.0	279.0	311.0
Software & Control
Sales and operating results of reportable segments
Sales	568.0	569.0	1,097.0	1,173.0
Software & Control \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	171.0	146.0	304.0	298.0
Lifecycle Services
Sales and operating results of reportable segments
Sales	537.0	583.0	1,083.0	1,104.0
Lifecycle Services \| Operating Segments
Sales and operating results of reportable segments
Segment operating earnings	$ 78.0	$ 97.0	$ 146.0	$ 151.0

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

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General Corporate - Net

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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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