composition of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Totals	$ 1,027,738	$ 927,413
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	347,695	340,847
Residential 5+ multifamily	36,094	34,478
Construction of residential 1-4 family	8,814	11,889
Home equity lines of credit	27,650	33,693
Residential real estate	420,253	420,907
Commercial	305,193	285,462
Construction of commercial	31,722	8,466
Commercial real estate	336,915	293,928
Farm land	3,040	3,455
Vacant land	13,912	7,713
Real estate secured	774,120	726,003
Commercial and industrial	226,662	169,285
Municipal	21,512	21,914
Consumer	7,661	6,349
Unallocated allowance
Totals	1,029,955	923,551
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	2,445	2,117
Residential 5+ multifamily	686	446
Construction of residential 1-4 family	65	75
Home equity lines of credit	232	197
Residential real estate	3,428	2,835
Commercial	6,298	3,333
Construction of commercial	596	104
Commercial real estate	6,894	3,437
Farm land	59	47
Vacant land	178	66
Real estate secured	10,559	6,385
Commercial and industrial	1,223	1,143
Municipal	43	46
Consumer	59	59
Unallocated allowance	1,207	569
Totals	13,091	8,202
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	4,306	5,452
Residential 5+ multifamily	964	977
Construction of residential 1-4 family
Home equity lines of credit	154	105
Residential real estate	5,424	6,534
Commercial	5,648	4,333
Construction of commercial
Commercial real estate	5,648	4,333
Farm land	158	186
Vacant land	167	180
Real estate secured	11,397	11,233
Commercial and industrial	486	126
Municipal
Consumer	26	36
Unallocated allowance
Totals	11,909	11,395
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	201	276
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit	20
Residential real estate	221	276
Commercial	248	409
Construction of commercial
Commercial real estate	248	409
Farm land
Vacant land	2	5
Real estate secured	471	690
Commercial and industrial	174	2
Municipal
Consumer	18	1
Unallocated allowance
Totals	663	693
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	352,001	346,299
Residential 5+ multifamily	37,058	35,455
Construction of residential 1-4 family	8,814	11,889
Home equity lines of credit	27,804	33,798
Residential real estate	425,677	427,441
Commercial	310,841	289,795
Construction of commercial	31,722	8,466
Commercial real estate	342,563	298,261
Farm land	3,198	3,641
Vacant land	14,079	7,893
Real estate secured	785,517	737,236
Commercial and industrial	227,148	169,411
Municipal	21,512	21,914
Consumer	7,687	6,385
Unallocated allowance
Totals	1,041,864	934,946
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	2,646	2,393
Residential 5+ multifamily	686	446
Construction of residential 1-4 family	65	75
Home equity lines of credit	252	197
Residential real estate	3,649	3,111
Commercial	6,546	3,742
Construction of commercial	596	104
Commercial real estate	7,142	3,846
Farm land	59	47
Vacant land	180	71
Real estate secured	11,030	7,075
Commercial and industrial	1,397	1,145
Municipal	43	46
Consumer	77	60
Unallocated allowance	1,207	569
Totals	$ 13,754	$ 8,895

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Total of (1) improvements, (2) held-for-sale, (3) land and land under development, (4) construction-in-process, (5) mortgage loans held-in-inventory, and (6) other real estate investments which are considered inventory due to being held for sale or disposition.

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