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Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon		2000.00%
Gain (loss) on corridor		10.00%
Defined Benefit Plan, Amortization of Gain (Loss)		$ (3.1)	$ (3.7)	$ (1.7)
Defined Contribution Plan, Cost		$ 9.1	$ 8.2	$ 7.3
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	$ (0.5)

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- Definition

Defined Benefit Plan, Expected Return on Plan Assets, Major Asset Classes, Time Horizon

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

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Amount of cost for defined contribution plan.

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