Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Sep. 30, 2023
Debt Instrument [Line Items]
Current maturities on debt	$ 15,000	$ 50,000
Debt issuance costs	(10,598)	(12,092)
Long-Term Debt, Excluding Current Maturities	2,028,652	1,811,658
Debt, Long-Term and Short-Term, Combined Amount	2,043,652	1,861,658
Senior Notes \| May 2018 Senior Notes
Debt Instrument [Line Items]
Senior Notes, Noncurrent	400,000	400,000
Senior Notes \| Dec 2019 and 2021 Senior Notes
Debt Instrument [Line Items]
Senior Notes, Noncurrent	900,000	900,000
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Line of Credit, Current	0	35,000
Line of Credit, Noncurrent	488,000	265,000
Revolving Credit Facility \| Loans Payable
Debt Instrument [Line Items]
Loans Payable to Bank, Current	15,000	15,000
Loans Payable to Bank, Noncurrent	$ 251,250	$ 258,750

Amount of debt and lease obligation, classified as current.

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