Borrowing Arrangements (Components Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Sep. 30, 2020
Debt instrument	$ 452.4	$ 452.5
Deferred financing costs	4.7	4.9
Current portion of long-term debt	1.1	1.1
Long-term debt	446.6	446.5
Unsecured Debt [Member]
5.5% Senior Notes	450.0	450.0
Other [Member]
Debt instrument	$ 2.4	$ 2.5

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.

+ References

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

+ References

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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