Leases - Lease Cost Components Schedule (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Finance lease expense:
Amortization of right-of use assets on finance leases	$ 13	$ 14	$ 41	$ 41
Interest on lease liabilities	1	1	2	4
Operating lease expense:	431	664	1,523	1,743
Variable lease cost:	34	39	104	118
Total lease expense	$ 479	$ 718	$ 1,670	$ 1,906