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Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2024	Sep. 30, 2023	Aug. 12, 2022
Debt Instrument
Long-term Debt, Including Current Maturities	$ 6,420.1	$ 6,049.6
Current portion of long-term debt	1.2	1.1
Unamortized Debt Issuance Costs, net	45.6	42.0
Plus: Unamortized premium and discount, net	24.5	32.5
Total Long-term Debt	6,397.8	6,039.0
Municipal Bonds
Debt Instrument
Long-term Debt	4.2	5.3
Term Loan
Debt Instrument
Long-term Debt	0.0	400.0
Revolving Credit Facility
Debt Instrument
Long-term Debt	300.0	0.0
2.50% convertible senior notes \| Senior Notes
Debt Instrument
Long-term Debt	$ 575.0	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	1,049.7
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	939.9	939.9
5.75% Senior Notes Maturing March 2027 \| Senior Notes
Debt Instrument
Long-term Debt	0.0	459.3
6.25% Senior Notes Maturing in February 2032 \| Senior Notes
Debt Instrument
Long-term Debt	$ 1,000.0	$ 0.0
Debt Instrument, Interest Rate, Stated Percentage	6.25%