Retirement Plans - Schedule of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2024 |
Mar. 31, 2023 |
Mar. 31, 2024 |
Mar. 31, 2023 |
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| Retirement Benefits [Abstract] | ||||
| Service cost | $ 2 | $ 1 | $ 3 | $ 2 |
| Interest cost | 5 | 5 | 10 | 9 |
| Expected return on plan assets | (3) | (3) | (6) | (6) |
| Net actuarial and settlement/curtailment (gain) loss | 0 | 0 | 0 | 8 |
| Net periodic benefit cost | $ 4 | $ 3 | $ 7 | $ 13 |
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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/exampleRef
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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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