Loans and Allowance for Loan Losses - Components of Recorded Investment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Recorded Investment in Loans:
Principal loan balance	$ 1,147,150	$ 1,109,416
Accrued interest receivable	5,034	4,585
Net deferred loan origination fees and costs	(1,383)	(2,327)
Recorded investment in loans	1,150,801	1,111,674
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	13,425	16,684
Collectively evaluated for impairment	1,137,376	1,094,990
Ending balance	1,150,801	1,111,674
Residential real estate [Member]
Recorded Investment in Loans:
Principal loan balance	205,129	191,781
Accrued interest receivable	638	644
Net deferred loan origination fees and costs	(295)	(156)
Recorded investment in loans	205,472	192,269
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	3,663	5,359
Collectively evaluated for impairment	201,809	186,910
Ending balance	205,472	192,269
Commercial real estate [Member]
Recorded Investment in Loans:
Principal loan balance	141,122	141,522
Accrued interest receivable	601	812
Net deferred loan origination fees and costs	(189)	(197)
Recorded investment in loans	141,534	142,137
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	1,088	1,134
Collectively evaluated for impairment	140,446	141,003
Ending balance	141,534	142,137
Single tenant net lease
Recorded Investment in Loans:
Principal loan balance	372,074	334,636
Accrued interest receivable	1,242	1,198
Net deferred loan origination fees and costs	(173)	(234)
Recorded investment in loans	373,143	335,600
Recorded Investment in Loans as Evaluated for Impairment:
Collectively evaluated for impairment	373,143	335,600
Ending balance	373,143	335,600
SBA commercial real estate
Recorded Investment in Loans:
Principal loan balance	57,556	55,508
Accrued interest receivable	528	387
Net deferred loan origination fees and costs	1,026	1,082
Recorded investment in loans	59,110	56,977
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	5,386	6,927
Collectively evaluated for impairment	53,724	50,050
Ending balance	59,110	56,977
Multifamily
Recorded Investment in Loans:
Principal loan balance	44,434	42,368
Accrued interest receivable	122	139
Net deferred loan origination fees and costs	(48)	(37)
Recorded investment in loans	44,508	42,470
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	648	698
Collectively evaluated for impairment	43,860	41,772
Ending balance	44,508	42,470
Residential Construction
Recorded Investment in Loans:
Principal loan balance	5,389	9,361
Accrued interest receivable	7	25
Net deferred loan origination fees and costs	(27)	(28)
Recorded investment in loans	5,369	9,358
Recorded Investment in Loans as Evaluated for Impairment:
Collectively evaluated for impairment	5,369	9,358
Ending balance	5,369	9,358
Commercial Construction
Recorded Investment in Loans:
Principal loan balance	9,193	6,941
Accrued interest receivable	30	24
Net deferred loan origination fees and costs	(28)	(26)
Recorded investment in loans	9,195	6,939
Recorded Investment in Loans as Evaluated for Impairment:
Collectively evaluated for impairment	9,195	6,939
Ending balance	9,195	6,939
Land and land development
Recorded Investment in Loans:
Principal loan balance	10,894	9,403
Accrued interest receivable	26	20
Net deferred loan origination fees and costs	(10)	(11)
Recorded investment in loans	10,910	9,412
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	4	2
Collectively evaluated for impairment	10,906	9,410
Ending balance	10,910	9,412
Commercial Business
Recorded Investment in Loans:
Principal loan balance	63,392	60,513
Accrued interest receivable	185	186
Net deferred loan origination fees and costs	46	43
Recorded investment in loans	63,623	60,742
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	1,706	1,670
Collectively evaluated for impairment	61,917	59,072
Ending balance	63,623	60,742
SBA commercial business
Recorded Investment in Loans:
Principal loan balance	182,167	206,807
Accrued interest receivable	1,495	975
Net deferred loan origination fees and costs	(1,664)	(2,740)
Recorded investment in loans	181,998	205,042
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	768	695
Collectively evaluated for impairment	181,230	204,347
Ending balance	181,998	205,042
Consumer
Recorded Investment in Loans:
Principal loan balance	55,800	50,576
Accrued interest receivable	160	175
Net deferred loan origination fees and costs	(21)	(23)
Recorded investment in loans	55,939	50,728
Recorded Investment in Loans as Evaluated for Impairment:
Individually evaluated for impairment	162	199
Collectively evaluated for impairment	55,777	50,529
Ending balance	$ 55,939	$ 50,728

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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