LONG-TERM DEBT - Summary of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Jun. 22, 2020
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	$ 1,541,416	$ 1,595,560
less: Current portion, Outstanding Balance	(12,840)	(12,653)
Long-term debt, Outstanding Balance, Non-current	1,528,576	1,582,907
Original Issuer Premium/(Discount)	(847)	(878)
Capitalized Fees & Expenses	(20,048)	(21,031)
Long-term debt, Balance Sheet	1,520,521	1,573,651
less: Current portion, Balance Sheet	(12,840)	(12,653)
Long-term debt, Balance Sheet, Non-current	1,507,681	1,560,998
Senior notes due 2028
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	974,775	974,775
Original Issuer Premium/(Discount)	254	266
Capitalized Fees & Expenses	(10,434)	(10,939)
Long-term debt, Balance Sheet	$ 964,595	$ 964,102
Coupon Interest Rate	5.75%	5.75%	5.75%
Term Loan B due 2029
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	$ 494,000	$ 496,000
Original Issuer Premium/(Discount)	(1,101)	(1,144)
Capitalized Fees & Expenses	(8,472)	(8,823)
Long-term debt, Balance Sheet	484,427	486,033
Revolver due 2025
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	45,100	97,328
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	(1,104)	(1,227)
Long-term debt, Balance Sheet	43,996	96,101
Finance lease - real estate
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	12,751	13,091
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	0	0
Long-term debt, Balance Sheet	12,751	13,091
Non US lines of credit
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	0	0
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	(4)	(2)
Long-term debt, Balance Sheet	(4)	(2)
Non US term loans
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	12,663	12,090
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	(21)	(27)
Long-term debt, Balance Sheet	12,642	12,063
Other long term debt
Debt Instrument [Line Items]
Long-term debt, Outstanding Balance	2,127	2,276
Original Issuer Premium/(Discount)	0	0
Capitalized Fees & Expenses	(13)	(13)
Long-term debt, Balance Sheet	$ 2,114	$ 2,263

Amount of long term capitalized fees and expenses.

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The current portion of long term debt gross value.

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The carrying amount of long-term debt, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities).

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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.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount (premium).

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

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