Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Debt Instrument [Line Items]
Current maturities on debt	$ 15,000	$ 15,000
Debt issuance costs	(8,900)	(9,729)
Long-Term Debt, Excluding Current Maturities	2,406,100	2,194,021
Debt, Long-Term and Short-Term, Combined Amount	2,421,100	2,209,021
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, Noncurrent	425,000	210,000
Revolving Credit Facility \| Loans Payable
Debt Instrument [Line Items]
Loans Payable to Bank, Current	15,000	15,000
Revolving Credit Facility \| Loans Payable \| The $300 Million Term Loan
Debt Instrument [Line Items]
Loans Payable to Bank, Noncurrent	240,000	243,750
Revolving Credit Facility \| Loans Payable \| The $450 Million Term Loan
Debt Instrument [Line Items]
Loans Payable to Bank, Noncurrent	$ 450,000	$ 450,000

Amount of debt and lease obligation, classified as current.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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