DEBT - Schedule of Unsecured Long-Term Debt Outstanding (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Long-term debt, gross
Face Amount	$ 2,082,880	$ 1,800,000
Unamortized Discount and Debt Issuance Cost	(18,937)	(17,818)
Book Value	2,063,943	1,782,182
Less: current portion of long-term debt
Face Amount	(6,859)	0
Unamortized Discount and Debt Issuance Cost	0	0
Book Value	(6,859)	0
Total long-term debt, net
Face Amount	2,076,021	1,800,000
Unamortized Discount and Debt Issuance Cost	(18,937)	(17,818)
Long-term debt, net	2,057,084	1,782,182
Unsecured Debt
Long-term debt, gross
Face Amount	1,800,000	1,800,000
Unamortized Discount and Debt Issuance Cost	(16,191)	(17,818)
Book Value	1,783,809	1,782,182
Secured Debt
Long-term debt, gross
Face Amount	82,880	0
Unamortized Discount and Debt Issuance Cost	(1,766)	0
Book Value	81,114	0
Due December 1, 2027
Long-term debt, gross
Face Amount	350,000	350,000
Unamortized Discount and Debt Issuance Cost	(2,326)	(2,907)
Book Value	347,674	347,093
Total long-term debt, net
Long-term debt, net	347,675	347,093
Due December 1, 2029
Long-term debt, gross
Face Amount	350,000	350,000
Unamortized Discount and Debt Issuance Cost	(3,398)	(3,703)
Book Value	346,602	346,297
Total long-term debt, net
Long-term debt, net	346,602	346,297
Due September 29, 2031
Long-term debt, gross
Face Amount	550,000	550,000
Unamortized Discount and Debt Issuance Cost	(3,664)	(4,262)
Book Value	546,336	545,738
Total long-term debt, net
Long-term debt, net	546,336	545,738
Due December 1, 2034
Long-term debt, gross
Face Amount	550,000	550,000
Unamortized Discount and Debt Issuance Cost	(6,803)	(6,946)
Book Value	543,197	543,054
Total long-term debt, net
Long-term debt, net	543,197	543,054
Due January 15, 2027
Long-term debt, gross
Face Amount	200,000	0
Unamortized Discount and Debt Issuance Cost	(980)	0
Book Value	199,020	0
Total long-term debt, net
Long-term debt, net	199,020
Due December 31, 2033
Long-term debt, gross
Face Amount	39,789	0
Unamortized Discount and Debt Issuance Cost	(888)	0
Book Value	38,901	0
Due December 31, 2034
Long-term debt, gross
Face Amount	43,091	0
Unamortized Discount and Debt Issuance Cost	(878)	0
Book Value	$ 42,213	$ 0

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

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

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