DEBT - Schedule of Unsecured Long-Term Debt Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024
Long-term debt
Face Amount	$ 1,800,000	$ 1,800,000
Unamortized Discount and Debt Issuance Cost	(18,326)	(17,818)
Long-term debt, net	1,781,674	1,782,182
Due December 1, 2027
Long-term debt, gross
Face Amount	350,000	350,000
Unamortized Discount and Debt Issuance Cost	(3,066)	(2,907)
Book Value	346,934	347,093
Due December 1, 2029
Long-term debt, gross
Face Amount	350,000	350,000
Unamortized Discount and Debt Issuance Cost	(3,932)	(3,703)
Book Value	346,068	346,297
Due September 29, 2031
Long-term debt, gross
Face Amount	550,000	550,000
Unamortized Discount and Debt Issuance Cost	(4,112)	(4,262)
Book Value	545,888	545,738
Due December 1, 2034
Long-term debt, gross
Face Amount	550,000	550,000
Unamortized Discount and Debt Issuance Cost	(7,216)	(6,946)
Book Value	$ 542,784	$ 543,054

Debt Instrument, Unamortized Discount (Premium) And Debt Issuance Costs, Net, Noncurrent

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- Definition

Long-Term Debt, Excluding Current Maturities, Gross

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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.

+ References

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Amount of unamortized debt discount (premium) and debt issuance costs.

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

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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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