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Borrowing Arrangements (Components Of Long-Term Debt) (Details) - USD ($) $ in Millions | Jun. 30, 2021 | May 28, 2021 | Sep. 30, 2020 | Jun. 12, 2018
--- | --- | --- | --- | ---
Debt instrument | $ 452.1 |  | $ 452.5 |
Deferred financing costs | (5.5) |  | (4.9) |
Current portion of long-term debt | (1.0) |  | (1.1) |
Long-term debt | 445.6 |  | 446.5 |
Other [Member] |  |  |  |
Debt instrument | 2.1 |  | 2.5 |
4.0% Senior Notes [Member] |  |  |  |
5.5% Senior Notes |  | $ 450.0 |  |
4.0% Senior Notes [Member] | Senior Notes |  |  |  |
5.5% Senior Notes | 450.0 |  | 0.0 |
5.5% Notes |  |  |  |
5.5% Senior Notes |  |  |  | $ 450.0
5.5% Notes | Senior Notes |  |  |  |
5.5% Senior Notes | $ 0.0 |  | $ 450.0 |

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