Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2024	Sep. 30, 2024
Debt Instrument
Long-term Debt, Including Current Maturities	$ 6,980.2	$ 6,845.1
Current portion of long-term debt	1.2	1.2
Unamortized Debt Issuance Costs, net	57.2	55.9
Plus: Unamortized premium and discount, net	22.6	23.6
Total Long-term Debt	6,944.4	6,811.6
Municipal Bonds
Debt Instrument
Long-term Debt	4.2	4.2
2.50% convertible senior notes \| Senior Notes
Debt Instrument
Long-term Debt	$ 575.0	575.0
Debt Instrument, Interest Rate, Stated Percentage	2.50%
4.50% Senior Notes Maturing in September 2031 \| Senior Notes
Debt Instrument
Long-term Debt	$ 980.6	980.6
4.625% Senior Notes Maturing April 2030 \| Senior Notes
Debt Instrument
Long-term Debt	1,385.4	1,385.4
5.50% Senior Notes Maturing in December 2029 \| Senior Notes
Debt Instrument
Long-term Debt	1,235.0	1,235.0
5.625% senior notes maturing January 2028 \| Senior Notes
Debt Instrument
Long-term Debt	0.0	464.9
6.25% Senior Notes Maturing in February 2032 \| Senior Notes
Debt Instrument
Long-term Debt	1,000.0	1,000.0
6.250% Senior Notes Maturing in October 2034 \| Senior Notes
Debt Instrument
Long-term Debt	$ 600.0	0.0
Debt Instrument, Interest Rate, Stated Percentage	6.25%
6.375% Senior Notes Maturing in March 2033 \| Senior Notes
Debt Instrument
Long-term Debt	$ 1,200.0	$ 1,200.0

Contractual interest rate for funds borrowed, under the debt agreement.

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