Business Segment Information - Narrative (Details) $ in Millions	3 Months Ended
	Dec. 31, 2025 USD ($) segment	Dec. 31, 2024 USD ($) segment
Segment Reporting Information [Line Items]
Sales | $	$ 2,105	$ 1,881
Number of operating segments | segment	3	3
Number of reportable segments | segment	3	3
Systems And Services | Revenue from Contract with Customer Benchmark | Customer Concentration Risk
Segment Reporting Information [Line Items]
Total sales (as a percent)	20.00%	20.00%
UNITED STATES
Segment Reporting Information [Line Items]
Sales | $	$ 1,237	$ 1,052