Borrowing Arrangements (Components Of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Sep. 30, 2021
Debt instrument	$ 452.1	$ 452.2
Deferred financing costs	(5.0)	(5.3)
Current portion of long-term debt	(1.0)	(1.0)
Long-term debt	446.1	445.9
Unsecured Debt [Member]
5.5% Senior Notes	450.0	450.0
Other [Member]
Debt instrument	$ 2.1	$ 2.2

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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