Business Segments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Net sales	$ 3,756	$ 3,291	$ 7,129	$ 6,447
Earnings	639	509	1,061	1,451
Gain from periodic distribution from retained subordinated interest in Vertiv (VRT)	0	0	0	453
Interest expense	(53)	(51)	(101)	(90)
Operating Segments [Member] \| Measurement & Analytical Instrumentation [Member]
Segment Reporting Information [Line Items]
Net sales	888	769	1,637	1,506
Earnings	229	176	404	346
Operating Segments [Member] \| Final Control
Segment Reporting Information [Line Items]
Net sales	992	884	1,854	1,701
Earnings	215	152	373	274
Operating Segments [Member] \| Discrete Automation
Segment Reporting Information [Line Items]
Net sales	683	644	1,301	1,261
Earnings	133	130	254	250
Operating Segments [Member] \| Safety & Productivity [Member]
Segment Reporting Information [Line Items]
Net sales	361	355	671	706
Earnings	83	65	146	130
Operating Segments [Member] \| Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	2,924	2,652	5,463	5,174
Earnings	660	523	1,177	1,000
Operating Segments [Member] \| AspenTech
Segment Reporting Information [Line Items]
Net sales	230	84	473	166
Earnings	(54)	(4)	(87)	(6)
Operating Segments [Member] \| Control Systems & Software
Segment Reporting Information [Line Items]
Net sales	623	573	1,229	1,143
Earnings	127	101	234	217
Operating Segments [Member] \| Software and Control
Segment Reporting Information [Line Items]
Net sales	853	657	1,702	1,309
Earnings	73	97	147	211
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Stock compensation	(40)	(43)	(142)	(77)
Unallocated pension and postretirement costs	46	25	91	51
Gain from periodic distribution from retained subordinated interest in Vertiv (VRT)	0	0	0	453
Corporate and other [Member]
Segment Reporting Information [Line Items]
Earnings	(47)	(42)	(111)	(97)
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales	(21)	(18)	(36)	(36)
Interest expense	$ (53)	$ (51)	$ (101)	$ (90)

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