LEASES - Weighted average remaining lease term and discount rate (Details)	Sep. 30, 2021	Sep. 30, 2020
LEASES
Operating lease, weighted-average remaining lease term (in years)	4 years 7 months 28 days	4 years 9 months 21 days
Finance lease, weighted-average remaining lease term (in years)	3 years 3 months	10 months 17 days
Operating lease, weighted-average discount rate (as a percent)	4.45%	5.23%
Finance lease, weighted-average discount rate (as a percent)	4.86%	5.87%