Debt (Maturities of Long-term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020
Principal maturities of long-term debt
2022	$ 484.0
2023	475.8
2024	492.5
2025	449.2
2026	662.7
Thereafter	5,120.5
Total	$ 7,684.7	$ 7,950.2

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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