OPERATING LEASE RIGHT-OF-USE ASSETS AND LIABILITIES - Lease Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Weighted-average discount rate	2.45%	2.38%
Weighted-average remaining lease term (years)	8 years 9 months 10 days	9 years 7 months 28 days
Lease expense	$ 3,997	$ 3,951	$ 4,431
Short-term and variable lease cost	75	142	194
ROU asset impairment	0	0	670
Sublease income	(1,300)	(1,409)	(1,267)
Total lease cost for operating leases	$ 2,772	$ 2,684	$ 4,028