Debt - Carrying Value (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Sep. 30, 2024
Current maturities on debt:
Less: debt issuance costs	$ (655)	$ 0
Current maturities on debt	399,345	15,000
Long-term debt:
Less: debt issuance costs	(19,791)	(9,729)
Long-term debt	2,380,209	2,194,021
Total debt	2,779,554	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 \| 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	$ 0	$ 210,000

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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