Pension Plans (Schedule of Changes Using Unobservable Inputs) (Details) - Pension Plan - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023
United States
Change in Plan Assets
Estimated fair value of plan assets at beginning of year	$ 222.2	$ 356.9
Foreign currency exchange rate changes	0.0	0.0
Estimated fair value of plan assets at end of year	238.1	222.2
International
Change in Plan Assets
Estimated fair value of plan assets at beginning of year	83.4	78.3
Foreign currency exchange rate changes	7.5	6.6
Estimated fair value of plan assets at end of year	94.8	83.4
Level 3 \| International
Change in Plan Assets
Estimated fair value of plan assets at end of year	53.6
Buy-in Insurance Agreement \| Level 3 \| International
Change in Plan Assets
Estimated fair value of plan assets at beginning of year	0.0
Purchases	51.8
Benefits paid	(1.5)
Foreign currency exchange rate changes	3.3
Estimated fair value of plan assets at end of year	$ 53.6	$ 0.0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount, measured using unobservable input, of decrease in plan asset of defined benefit plan from settlement of trade associated with underlying investment.

+ References

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- Definition

Amount, measured using unobservable input, of increase in plan asset of defined benefit plan from purchase.

+ References

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