Retirement Plans (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Retirement Benefits [Abstract] | ||||
| Service cost | $ 1 | $ 1 | $ 5 | $ 4 |
| Interest cost | 5 | 4 | 14 | 13 |
| Expected return on plan assets | (4) | (3) | (11) | (10) |
| Net actuarial and settlement/curtailment loss | 0 | 0 | 2 | 0 |
| Net periodic benefit cost | $ 2 | $ 2 | $ 10 | $ 7 |
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- Definition Defined Benefit Plan, Net Actuarial And Settlement And Curtailment Gain (Loss) No definition available.
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- References No definition available.
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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