Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Oct. 01, 2019
Lessee, Lease, Description [Line Items]
Operating lease, renewal term	5 years
Operating lease right-of-use ("ROU") assets	$ 2,283	$ 2,587	$ 2,890
Operating lease cost	395	377
Short-term lease cost	0	0
Total lease cost	395	377
Operating cash flows from operating leases	$ 327	$ 318
Weighted average remaining lease term-operating leases	8 years 5 months 8 days	9 years 2 months 26 days
Weighted average discount rate-operating leases	2.24%	2.22%
Minimum
Lessee, Lease, Description [Line Items]
Operating leases, term of contract	10 months
Maximum
Lessee, Lease, Description [Line Items]
Operating leases, term of contract	10 years