Debt - Carrying Value (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Current maturities on debt:
Less: debt issuance costs	$ (459)	$ 0
Current maturities on debt	399,541	15,000
Long-term debt:
Less: debt issuance costs	(18,850)	(9,729)
Long-term debt	2,656,150	2,194,021
Total	3,055,691	2,209,021
Loans Payable \| The $300 Million Term Loan \| Unsecured Debt
Current maturities on debt:
Current maturities on debt, gross	0	15,000
Long-term debt:
Long-term debt, gross	0	243,750
Loans Payable \| The $450 Million Term Loan \| Unsecured Debt
Long-term debt:
Long-term debt, gross	0	450,000
Senior Notes
Long-term debt:
Total	2,800,000
Senior Notes \| The 2018 Senior Notes
Current maturities on debt:
Current maturities on debt, gross	400,000	0
Long-term debt:
Long-term debt, gross	0	400,000
Senior Notes \| The 2019 Senior Notes and the 2021 Senior Notes
Long-term debt:
Long-term debt, gross	900,000	900,000
Senior Notes \| The 2025 Senior Notes
Long-term debt:
Long-term debt, gross	1,500,000	0
Revolving line of credit \| Revolving Credit Facility
Long-term debt:
Long-term debt, gross	$ 275,000	$ 210,000

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