Short-Term and Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Current portion of long-term debt	$ 608.8	$ 609.1
Reported Value Measurement
Debt Instrument [Line Items]
Current portion of long-term debt	608.8	609.1
Long-term Debt	2,868.1	2,867.8
Estimate of Fair Value Measurement
Debt Instrument [Line Items]
Current portion of long-term debt	598.6	589.1
Estimate of Fair Value Measurement | Fair Value, Inputs, Level 2
Debt Instrument [Line Items]
Long-term Debt	$ 2,638.2	$ 2,485.4