9. LEASES - Weighted-average Remaining Lease Terms (Details)	Dec. 31, 2023	Sep. 30, 2023
Leases [Abstract]
Weighted-average remaining lease term - operating leases	3 years 6 months	3 years 9 months 18 days
Weighted-average remaining lease term - finance leases	8 months 12 days	10 months 24 days
Weighted-average discount rate - operating leases	5.40%	5.40%
Weighted-average discount rate - finance leases	5.50%	5.50%