LONG-TERM DEBT - Summary of Interest Expense Incurred (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Instrument [Line Items]
Cash Interest, Capitalized Interest	$ (38)	$ (76)	$ (49)	$ (230)
Cash Interest	24,619	22,835	72,100	58,358
Amort. Debt (Premium)/Discount	31	49	93	55
Amort. Debt Issuance Costs & Other Fees	991	1,138	2,975	2,698
Total Interest Expense	$ 25,641	$ 24,022	$ 75,168	$ 61,111
Senior notes due 2028
Debt Instrument [Line Items]
Effective Interest Rate	6.00%	6.00%	6.00%	6.00%
Cash Interest, Including Amounts Capitalized	$ 14,013	$ 14,340	$ 42,037	$ 43,090
Amort. Debt (Premium)/Discount	(12)	(12)	(36)	(36)
Amort. Debt Issuance Costs & Other Fees	505	516	1,515	1,552
Total Interest Expense	$ 14,506	$ 14,844	$ 43,516	$ 44,606
Term Loan B due 2029
Debt Instrument [Line Items]
Effective Interest Rate	7.80%	3.90%	7.30%	3.70%
Cash Interest, Including Amounts Capitalized	$ 9,208	$ 7,129	$ 25,753	$ 11,896
Amort. Debt (Premium)/Discount	43	61	129	91
Amort. Debt Issuance Costs & Other Fees	351	485	1,054	717
Total Interest Expense	9,602	7,675	26,936	12,704
Revolver due 2025
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	905	1,056	2,922	2,307
Amort. Debt (Premium)/Discount	0	0	0	0
Amort. Debt Issuance Costs & Other Fees	123	123	368	368
Total Interest Expense	$ 1,028	$ 1,179	$ 3,290	$ 2,675
Finance lease - real estate
Debt Instrument [Line Items]
Effective Interest Rate	5.60%	5.60%	5.60%	5.60%
Cash Interest, Including Amounts Capitalized	$ 168	$ 187	$ 520	$ 577
Amort. Debt (Premium)/Discount	0	0	0	0
Amort. Debt Issuance Costs & Other Fees	0	0	0	4
Total Interest Expense	168	187	520	581
Non US lines of credit
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	259	4	619	14
Amort. Debt (Premium)/Discount	0	0	0	0
Amort. Debt Issuance Costs & Other Fees	12	5	37	12
Total Interest Expense	271	9	656	26
Non US term loans
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	0	141	0	492
Amort. Debt (Premium)/Discount	0	0	0	0
Amort. Debt Issuance Costs & Other Fees	0	9	0	44
Total Interest Expense	0	150	0	536
Other long term debt
Debt Instrument [Line Items]
Cash Interest, Including Amounts Capitalized	104	54	298	212
Amort. Debt (Premium)/Discount	0	0	0	0
Amort. Debt Issuance Costs & Other Fees	0	0	1	1
Total Interest Expense	$ 104	$ 54	$ 299	$ 213