Debt - Schedule of Short-Term Borrowings and Long Term Debt (Details) - USD ($)	Jun. 30, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Debt issuance costs and discounts	$ (12,600,000)	$ (12,400,000)
Total debt	1,591,500,000	1,687,600,000
Current portion of long-term debt	23,700,000	162,500,000
Long-term debt	1,567,800,000	1,525,100,000
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	469,100,000	460,000,000.0
Term Loan | Line of Credit | Revolver (a)
Debt Instrument [Line Items]
Debt gross	475,000,000
Total borrowing capacity remaining	471,200,000
Letters of credit outstanding	3,800,000
Trade Receivables Facility | Line of Credit | Secured Debt
Debt Instrument [Line Items]
Long-term debt	$ 0	$ 105,000,000.0