OTHER FINANCIAL DATA - Depreciation and Amortization Expense Components (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Business Acquisition [Line Items]
Depreciation expense	$ 323	$ 287	$ 312
Amortization of intangibles (includes $108, $196 and $197 reported in Cost of Sales in 2021, 2022 and 2023, respectively) (a)	1,274	678	444
Amortization of capitalized software	92	86	86
Total	1,689	1,051	842
Amortization if intangibles reported in Cost of Sales	197	196	108
Amortization of intangible assets	1,366	764	530
NI Acquisition
Business Acquisition [Line Items]
Amortization of intangible assets	560
Heritage AspenTech
Business Acquisition [Line Items]
Amortization of intangible assets	$ 398	$ 397	148
Amortization of intangibles - related restructuring			$ 14