LONG-TERM DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Outstanding Balance	$ 1,411,793	$ 1,423,811
less: Current portion	(8,018)	(8,033)
Long-term debt	1,403,775	1,415,778
Original Issuer Premium/(Discount)	(244)	(340)
Capitalized Fees & Expenses	(8,695)	(11,162)
Balance Sheet	1,402,854	1,412,309
less: Current portion	(8,018)	(8,033)
Long-term debt	1,394,836	1,404,276
Senior notes due 2028
Debt Instrument [Line Items]
Outstanding Balance	974,775	974,775
Original Issuer Premium/(Discount)	97	121
Capitalized Fees & Expenses	(3,871)	(4,880)
Balance Sheet	$ 971,001	$ 970,016
Coupon Interest Rate	5.75%	5.75%
Term loan B due 2029
Debt Instrument [Line Items]
Outstanding Balance	$ 387,000	$ 449,000
Original Issuer Premium/(Discount)	(341)	(461)
Capitalized Fees & Expenses	(3,084)	(4,169)
Balance Sheet	383,575	444,370
Revolver due 2028
Debt Instrument [Line Items]
Outstanding Balance	50,000	0
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	(1,740)	(2,113)
Balance Sheet	48,260	(2,113)
Other debt
Debt Instrument [Line Items]
Outstanding Balance	18	36
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	0	0
Balance Sheet	$ 18	$ 36

Amount of long term capitalized fees and expenses.

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