Debt - Schedule of Short-Term Borrowings and Long Term Debt (Details) - USD ($)	Dec. 31, 2023	Sep. 30, 2023
Debt Instrument [Line Items]
Debt issuance costs and discounts	$ (11,600,000)	$ (12,000,000.0)
Total debt	1,580,600,000	1,586,100,000
Current portion of long-term debt	23,800,000	23,800,000
Long-term debt	1,556,800,000	1,562,300,000
Line of Credit | Revolver (a)
Debt Instrument [Line Items]
Long-term debt	0	0
2031 Notes | Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount	535,000,000.0	535,000,000.0
2030 Notes | Senior Notes
Debt Instrument [Line Items]
Aggregate principal amount	600,000,000.0	600,000,000.0
Term Loan | Line of Credit
Debt Instrument [Line Items]
Debt gross	457,200,000	$ 463,100,000
Term Loan | Line of Credit | Revolver (a)
Debt Instrument [Line Items]
Debt gross	475,000,000
Total borrowing capacity remaining	471,600,000
Letters of credit outstanding	$ 3,400,000