BUSINESS SEGMENTS - Schedule of Segment Reporting Information, by Segment (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2022	Mar. 31, 2025	Mar. 31, 2024	Sep. 30, 2023
Segment Reporting Information [Line Items]
Net sales	$ 4,432	$ 4,376		$ 8,608	$ 8,493
Earnings (Loss)	629	711		1,404	886
Gain on subordinated interest		0		0	79
Interest expense	(41)	(57)		(50)	(101)
Expense	21	30		32	113
Acquisition/divestiture fees and related costs	144	5		157	85
Loss on divestiture of business	0	39		0
Amortization of acquisition-related inventory step-up				0	231
National Instruments
Segment Reporting Information [Line Items]
Net sales						$ 170
Expense		10			36
Acquisition/divestiture fees and related costs	160	16	$ 69	179	146
AspenTech
Segment Reporting Information [Line Items]
Expense				1
Restructuring Charges | National Instruments
Segment Reporting Information [Line Items]
Stock compensation	3	14		5	44
Restructuring Charges | AspenTech
Segment Reporting Information [Line Items]
Stock compensation				6
Software and Control
Segment Reporting Information [Line Items]
Expense	10	17		11	58
Operating Segments | Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	3,029	3,061		5,872	5,883
Earnings (Loss)	725	732		1,412	1,326
Expense	9	2		18	18
Operating Segments | Software and Control
Segment Reporting Information [Line Items]
Net sales	1,421	1,332
Earnings (Loss)	215	64
Operating Segments | Final Control | Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	1,073	1,051		2,049	1,991
Earnings (Loss)	267	259		503	453
Expense	2	(7)		4	(4)
Operating Segments | Measurement & Analytical | Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	1,002	1,013		1,977	1,960
Earnings (Loss)	266	274		551	509
Expense	2	1		3	4
Operating Segments | Discrete Automation | Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	615	632		1,195	1,245
Earnings (Loss)	117	116		215	213
Expense	5	7		11	17
Operating Segments | Safety & Productivity | Intelligent Devices
Segment Reporting Information [Line Items]
Net sales	339	365		651	687
Earnings (Loss)	75	83		143	151
Expense	0	1		0	1
Operating Segments | Control Systems & Software | Software and Control
Segment Reporting Information [Line Items]
Net sales	1,062	965		2,055	1,897
Earnings (Loss)	239	143		446	257
Expense	6	3		8	4
Operating Segments | Test & Measurement | Software and Control
Segment Reporting Information [Line Items]
Net sales	359	367		718	749
Earnings (Loss)	(24)	(79)		(37)	(157)
Expense	4	14		3	54
Operating Segments | Software and Control | Software and Control
Segment Reporting Information [Line Items]
Net sales				2,773	2,646
Earnings (Loss)				409	100
Segment Reconciling
Segment Reporting Information [Line Items]
Stock compensation	(59)	(73)		(127)	(147)
Unallocated pension and postretirement costs	27	38		55	69
Gain on subordinated interest	0	79		0	79
Segment Reconciling | Related Party
Segment Reporting Information [Line Items]
Interest income	0	31		0	62
Corporate and other
Segment Reporting Information [Line Items]
Earnings (Loss)	(238)	(103)		(295)	(502)
Expense	2	11		3	37
Corporate and other | National Instruments
Segment Reporting Information [Line Items]
Expense		11			37
Corporate and other | AspenTech
Segment Reporting Information [Line Items]
Expense	1			1
Eliminations/Interest
Segment Reporting Information [Line Items]
Net sales	(18)	(17)		(37)	(36)
Interest expense	$ (41)	$ (57)		$ (50)	$ (101)