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Segment Information (Narrative) (Details) - Customer Concentration Risk [Member] - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2022
Major Customers, Group One | Sales Revenue, Goods, Gross [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Concentration risk, percentage | 20.00% | 18.00% | 21.00%
Major Customers, Group One | Accounts Receivable [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Accounts and Other Receivables, Net, Current | $ 59.1 |  | $ 46.4
Major Customers, Group Two | Sales Revenue, Goods, Gross [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Concentration risk, percentage | 18.00% | 18.00% | 20.00%
Major Customers, Group Two | Accounts Receivable [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Accounts and Other Receivables, Net, Current | $ 36.9 | $ 37.7 |

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