composition of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	$ 368,801	$ 352,001
Residential 5+ multifamily	46,237	37,058
Construction of residential 1-4 family	15,429	8,814
Home equity lines of credit	24,001	27,804
Residential real estate	454,468	425,677
Commercial	314,820	310,841
Construction of commercial	47,145	31,722
Commercial real estate	361,965	342,563
Farm land	3,409	3,198
Vacant land	13,698	14,079
Real estate secured	833,540	785,517
Commercial and industrial	208,180	227,148
Municipal	18,061	21,512
Consumer	11,152	7,687
Totals	1,057,451	1,027,738
Allowance For Loan And Lease Losses Collectively Evaluated Loans [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	365,721	347,695
Residential 5+ multifamily	45,283	36,094
Construction of residential 1-4 family	15,429	8,814
Home equity lines of credit	23,915	27,650
Residential real estate	450,348	420,253
Commercial	310,947	305,193
Construction of commercial	47,145	31,722
Commercial real estate	358,092	336,915
Farm land	2,833	3,040
Vacant land	13,663	13,912
Real estate secured	824,936	774,120
Commercial and industrial	207,859	226,662
Municipal	18,061	21,512
Consumer	11,134	7,661
Unallocated allowance
Totals	1,061,990	1,029,955
SEC Schedule, 12-09, Allowance, Loan and Lease Loss, Real Estate [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	2,737	2,445
Residential 5+ multifamily	701	686
Construction of residential 1-4 family	136	65
Home equity lines of credit	196	232
Residential real estate	3,770	3,428
Commercial	6,123	6,298
Construction of commercial	786	596
Commercial real estate	6,909	6,894
Farm land	31	59
Vacant land	87	178
Real estate secured	10,797	10,559
Commercial and industrial	1,288	1,223
Municipal	31	43
Consumer	115	59
Unallocated allowance	847	1,207
Totals	13,078	13,091
Allowance For Loan And Lease Losses Individually Evaluated Loans [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	3,080	4,306
Residential 5+ multifamily	954	964
Construction of residential 1-4 family
Home equity lines of credit	86	154
Residential real estate	4,120	5,424
Commercial	3,873	5,648
Construction of commercial
Commercial real estate	3,873	5,648
Farm land	576	158
Vacant land	35	167
Real estate secured	8,604	11,397
Commercial and industrial	321	486
Municipal
Consumer	18	26
Unallocated allowance
Totals	8,943	11,909
SEC Schedule, 12-09, Allowance, Loan and Lease Loss [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	3	201
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit		20
Residential real estate	3	221
Commercial	43	248
Construction of commercial
Commercial real estate	43	248
Farm land
Vacant land		2
Real estate secured	46	471
Commercial and industrial	44	174
Municipal
Consumer		18
Unallocated allowance
Totals	90	663
Allowance For Loan And Lease Losses Total Portfolio Loans [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	368,801	352,001
Residential 5+ multifamily	46,237	37,058
Construction of residential 1-4 family	15,429	8,814
Home equity lines of credit	24,001	27,804
Residential real estate	454,468	425,677
Commercial	314,820	310,841
Construction of commercial	47,145	31,722
Commercial real estate	361,965	342,563
Farm land	3,409	3,198
Vacant land	13,698	14,079
Real estate secured	833,540	785,517
Commercial and industrial	208,180	227,148
Municipal	18,061	21,512
Consumer	11,152	7,687
Unallocated allowance
Totals	1,070,933	1,041,864
Allowance For Loan And Lease Losses Total Portfolio Allowance [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	2,740	2,646
Residential 5+ multifamily	701	686
Construction of residential 1-4 family	136	65
Home equity lines of credit	196	252
Residential real estate	3,773	3,649
Commercial	6,166	6,546
Construction of commercial	786	596
Commercial real estate	6,952	7,142
Farm land	31	59
Vacant land	87	180
Real estate secured	10,843	11,030
Commercial and industrial	1,332	1,397
Municipal	31	43
Consumer	115	77
Unallocated allowance	847	1,207
Totals	$ 13,168	$ 13,754

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