Pension Benefit Obligations - Excess of Plan Assets (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
United States
Additional year-end information for pension plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	$ 175.1	$ 168.8	$ 184.8
Accumulated benefit obligation	175.1	168.8	184.8
Fair value of plan assets	109.0	98.8	101.4
Expected employer contributions in next fiscal year	11.2
International
Additional year-end information for pension plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	649.8	628.1	601.4
Accumulated benefit obligation	649.8	628.1	600.1
Fair value of plan assets	547.1	$ 506.5	$ 456.9
Expected employer contributions in next fiscal year	$ 24.2

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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-Topic 715
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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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