Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Current maturities on debt	$ 15,000	$ 50,000
Debt issuance costs	(9,729)	(12,092)
Long-term debt	2,194,021	1,811,658
Debt, Long-Term and Short-Term, Combined Amount	2,209,021	1,861,658
The 2018 Senior Notes
Debt Instrument [Line Items]
Senior Notes, Non-current	400,000	400,000
The 2019 and 2021 Senior Notes
Debt Instrument [Line Items]
Senior Notes, Non-current	900,000	900,000
Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit, Current	0	35,000
Revolving Credit Facility \| The $300 Million Term Loan
Debt Instrument [Line Items]
Loans Payable to Bank, Current	15,000	15,000
Loans Payable to Bank, Noncurrent	243,750	258,750
Revolving Credit Facility \| The $450 Million Term Loan
Debt Instrument [Line Items]
Loans Payable to Bank, Noncurrent	450,000	0
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Long-Term Line of Credit, Noncurrent	$ 210,000	$ 265,000

Amount of debt and lease obligation, classified as current.

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