LONG-TERM DEBT - Summary of Interest Expense Incurred (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Cash Interest, Capitalized Interest	$ (2)	$ (73)
Cash Interest	23,625	15,027
Amort. Debt (Premium)/Discount	31	(12)
Amort. Debt Issuance Costs & Other Fees	992	666
Total Interest Expense	$ 24,648	$ 15,681
Senior notes due 2028
Debt Instrument [Line Items]
Effective Interest Rate	5.90%	5.90%
Cash Interest, Including Amounts Capitalized	$ 14,012	$ 14,375
Amort. Debt (Premium)/Discount	(12)	(12)
Amort. Debt Issuance Costs & Other Fees	505	518
Total Interest Expense	14,505	14,881
Term Loan B due 2029
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	7,808	0
Amort. Debt (Premium)/Discount	43	0
Amort. Debt Issuance Costs & Other Fees	351	0
Total Interest Expense	8,202	0
Revolver due 2025
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	1,344	261
Amort. Debt (Premium)/Discount	0	0
Amort. Debt Issuance Costs & Other Fees	123	122
Total Interest Expense	$ 1,467	$ 383
Finance lease - real estate
Debt Instrument [Line Items]
Effective Interest Rate	5.60%	5.60%
Cash Interest, Including Amounts Capitalized	$ 178	$ 198
Amort. Debt (Premium)/Discount	0	0
Amort. Debt Issuance Costs & Other Fees	0	4
Total Interest Expense	178	202
Non US lines of credit
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	155	3
Amort. Debt (Premium)/Discount	0	0
Amort. Debt Issuance Costs & Other Fees	13	4
Total Interest Expense	168	7
Non US term loans
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	0	166
Amort. Debt (Premium)/Discount	0	0
Amort. Debt Issuance Costs & Other Fees	0	17
Total Interest Expense	0	183
Other long term debt
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	130	97
Amort. Debt (Premium)/Discount	0	0
Amort. Debt Issuance Costs & Other Fees	0	1
Total Interest Expense	$ 130	$ 98

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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