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Debt - Schedule of Long Term Debt (Details) - USD ($)	Sep. 30, 2025	Sep. 30, 2024	Apr. 16, 2024
Debt Instrument [Line Items]
Debt, gross	$ 1,080,600,000
Debt issuance costs and discounts	(6,600,000)	$ (5,600,000)
Total debt	1,074,000,000	1,093,800,000
Current portion of long-term debt	23,800,000	23,800,000
Long-term debt	1,050,200,000	1,070,000,000
Line of Credit \| Revolver
Debt Instrument [Line Items]
Debt, gross	130,000,000.0	125,000,000.0
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
Term Loan \| Line of Credit \| Secured Debt
Debt Instrument [Line Items]
Debt, gross	$ 415,600,000	$ 439,400,000