DEBT - Additional information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023
DEBT
Available to borrow under the credit facility	$ 303,000		$ 303,000
Cash on hand	59,436		59,436		$ 41,866
Current maturities of long-term debt	20,000		20,000
Letters of credit outstanding, amount	$ 5,800		$ 5,800
Debt weighted average interest rate	6.80%	6.00%	6.80%	5.30%
Revolving Credit Facility
DEBT
Line of credit facility, amount outstanding	$ 500,000		$ 500,000
Line of credit facility, commitment fee amount			$ 250,000
Minimum
DEBT
Facility fee			0.125%
Maximum
DEBT
Incremental term loan	$ 250,000		$ 250,000
Facility fee			0.25%