Leases - Lease Cost Components Schedule (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Finance lease expense:
Amortization of right-of use assets on finance leases	$ 13	$ 14	$ 27	$ 27
Interest on lease liabilities	1	1	2	3
Operating lease expense:	540	543	1,092	1,079
Variable lease cost:	35	39	69	79
Total lease expense	$ 589	$ 597	$ 1,190	$ 1,188