Leases - Schedule of Additional Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Assets:
Operating lease assets	$ 463,479	$ 432,166
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Operating lease assets	Operating lease assets
Finance lease assets	$ 74,400	$ 62,100
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property, Plant and Equipment, Net	Property, Plant and Equipment, Net
Total lease assets	$ 537,900	$ 494,300
Current:
Operating lease liabilities	$ 132,400	$ 135,100
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued Liabilities, Current	Accrued Liabilities, Current
Finance lease liabilities	$ 31,900	$ 25,500
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Long-Term Debt and Lease Obligation, Current	Long-Term Debt and Lease Obligation, Current
Total current lease liabilities	$ 164,300	$ 160,600
Non-current:
Operating lease liabilities	$ 515,998	$ 510,573
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Operating lease liabilities	Operating lease liabilities
Finance lease liabilities	$ 44,300	$ 35,700
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Long-term debt	Long-term debt
Total non-current lease liabilities	$ 560,300	$ 546,300
Weighted average remaining lease term (in years):
Operating leases (in years)	6 years 1 month 6 days	6 years 2 months 12 days	6 years 4 months 24 days
Finance leases (in years)	2 years 8 months 12 days	2 years 7 months 6 days	2 years 10 months 24 days
Weighted average discount rates:
Operating leases (as percent)	5.20%	5.10%	4.30%
Finance leases (as percent)	4.80%	4.40%	4.10%