LEASES - Components of lease costs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Leases
Option to extend			true
Finance lease cost
Amortization of right-of-use assets	$ 492	$ 622	$ 985	$ 1,245
Interest on lease liabilities	311	198	623	335
Operating lease cost	1,424	1,402	2,877	2,750
Total lease costs	$ 2,227	$ 2,222	$ 4,485	$ 4,330
Maximum
Leases
Lease term	20 years		20 years