Debt (Details) - USD ($)	Feb. 06, 2023	Jun. 30, 2023		Sep. 30, 2022
Debt Instrument [Line Items]
Total		$ 1,335,000,000		$ 1,405,000,000
Long-term debt		1,323,100,000		1,391,400,000
Notes payable		17,700,000		19,000,000.0
Unamortized debt issuance costs		11,900,000	[1]	13,600,000
Senior Secured Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Issued, Principal	$ 425,000,000.0
Senior notes | Senior Notes, Due 2028
Debt Instrument [Line Items]
Total		750,000,000.0		750,000,000.0
Unamortized debt issuance costs		7,200,000		8,300,000
Senior notes | Senior Notes, Due 2029
Debt Instrument [Line Items]
Total		500,000,000.0		500,000,000.0
Unamortized debt issuance costs		4,700,000		5,300,000
Revolving credit facility
Debt Instrument [Line Items]
Total		$ 85,000,000.0	[2]	$ 155,000,000.0

[1] As of June 30, 2023, the balance for the Senior Notes due 2028 and the Senior Notes due 2029 are reflected net of debt issuance costs of $7.2 and $4.7, respectively. As of September 30, 2022, the balance for the Senior Notes due 2028 and the Senior Notes due 2029 are reflected net of debt issuance costs of $8.3 and $5.3, respectively.

[2] The U.S. revolving credit facility matures in April 2025.