Leases - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2014 USD ($)	Sep. 30, 2024 USD ($) extensionOption	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease payments		$ 79,700	$ 76,700	$ 72,300
Payments of finance leases		492	275	0
Interest on financing lease liabilities		$ 200	100	0
Initial term of lease (in years)		10 years
Total lease liabilities		$ 291,424
Impairment charges			4,300
Operating lease right of use asset non cash		55,300	66,500	$ 69,400
Non cash increase in finance lease, lease liabilities		$ 200	$ 2,500
Corporate Office Lease, Two Five-Year Extension Options
Lessee, Lease, Description [Line Items]
Initial term of lease (in years)	13 years
Annual rent at lease inception	$ 2,500
Annual rent in the terminal year of lease	$ 3,900
Number of extension options | extensionOption		2
Renewable term of lease (in years)		5 years
Total lease liabilities		$ 15,400
Estimated future minimum sublease payments		$ 5,100