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Retirement Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
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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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