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Summary of Significant Accounting Policies (Schedule of Reserves for Excess and Obsolete Inventory) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of year | $ 16.5 | $ 14.8 | $ 11.7
Provision charged to expense | (3.8) | (1.8) | (5.9)
Inventory Valuation Allowances and Reserves, Deduction | (2.5) | (1.4) | (3.6)
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment | (1.0) | 1.3 | 0.8
Balance at end of year | $ 16.8 | $ 16.5 | $ 14.8

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