Business Segments (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Net sales	$ 3,373	$ 3,156
Earnings	422	942
Gain from periodic distribution from retained subordinated interest in Vertiv (VRT)	0	453
Gain (loss) on sale of business	2,780	0
Interest expense	(48)	(39)
Operating Segments [Member] \| Measurement & Analytical Instrumentation [Member]
Segment Reporting Information [Line Items]
Net sales	749	737
Earnings	175	170
Operating Segments [Member] \| Final Control
Segment Reporting Information [Line Items]
Net sales	862	817
Earnings	158	122
Operating Segments [Member] \| Discrete Automation
Segment Reporting Information [Line Items]
Net sales	618	617
Earnings	121	120
Operating Segments [Member] \| Safety & Productivity [Member]
Segment Reporting Information [Line Items]
Net sales	310	351
Earnings	63	65
Operating Segments [Member] \| Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	2,539	2,522
Earnings	517	477
Operating Segments [Member] \| AspenTech
Segment Reporting Information [Line Items]
Net sales	243	82
Earnings	(33)	(2)
Operating Segments [Member] \| Control Systems & Software
Segment Reporting Information [Line Items]
Net sales	606	570
Earnings	107	116
Operating Segments [Member] \| Software and Control
Segment Reporting Information [Line Items]
Net sales	849	652
Earnings	74	114
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Stock compensation	(102)	(34)
Unallocated pension and postretirement costs	45	26
Gain from periodic distribution from retained subordinated interest in Vertiv (VRT)	0	453
Corporate and other [Member]
Segment Reporting Information [Line Items]
Earnings	(64)	(55)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(15)	(18)
Interest expense	$ (48)	$ (39)

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