RESTRUCTURING COSTS - Narrative (Details) $ in Millions	12 Months Ended
	Sep. 30, 2024 USD ($) position facilty	Sep. 30, 2023 USD ($) position facilty	Sep. 30, 2022 USD ($) facilty position	Sep. 30, 2025 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 228	$ 72	$ 75
Number of positions eliminated | position	2,250	700	2,150
Total number of facilities exited | facilty	22	10	7
Costs incurred related to restructuring actions	$ 16	$ 20	$ 40
Corporate and other
Restructuring Cost and Reserve [Line Items]
Restructuring costs	51	$ 14	$ 13
Corporate and other | National Instruments
Restructuring Cost and Reserve [Line Items]
Restructuring costs	$ 43
Forecast
Restructuring Cost and Reserve [Line Items]
Restructuring costs, expected future cost				$ 120