composition of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Totals	$ 1,032,345	$ 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	350,241	347,695
Residential 5+ multifamily	36,010	36,094
Construction of residential 1-4 family	12,251	8,814
Home equity lines of credit	25,115	27,650
Residential real estate	423,617	420,253
Commercial	308,165	305,193
Construction of commercial	41,983	31,722
Commercial real estate	350,148	336,915
Farm land	2,935	3,040
Vacant land	12,846	13,912
Real estate secured	789,546	774,120
Commercial and industrial	218,307	226,662
Municipal	18,341	21,512
Consumer	9,522	7,661
Unallocated allowance
Totals	1,035,716	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	2,374	2,445
Residential 5+ multifamily	545	686
Construction of residential 1-4 family	95	65
Home equity lines of credit	190	232
Residential real estate	3,204	3,428
Commercial	6,167	6,298
Construction of commercial	668	596
Commercial real estate	6,835	6,894
Farm land	32	59
Vacant land	87	178
Real estate secured	10,158	10,559
Commercial and industrial	1,141	1,223
Municipal	32	43
Consumer	66	59
Unallocated allowance	1,148	1,207
Totals	12,545	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	3,411	4,306
Residential 5+ multifamily	962	964
Construction of residential 1-4 family
Home equity lines of credit	147	154
Residential real estate	4,520	5,424
Commercial	4,481	5,648
Construction of commercial
Commercial real estate	4,481	5,648
Farm land	594	158
Vacant land	160	167
Real estate secured	9,755	11,397
Commercial and industrial	450	486
Municipal
Consumer	21	26
Unallocated allowance
Totals	10,226	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	45	248
Construction of commercial
Commercial real estate	45	248
Farm land
Vacant land		2
Real estate secured	48	471
Commercial and industrial	115	174
Municipal
Consumer		18
Unallocated allowance
Totals	163	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	353,652	352,001
Residential 5+ multifamily	36,972	37,058
Construction of residential 1-4 family	12,251	8,814
Home equity lines of credit	25,262	27,804
Residential real estate	428,137	425,677
Commercial	312,646	310,841
Construction of commercial	41,983	31,722
Commercial real estate	354,629	342,563
Farm land	3,529	3,198
Vacant land	13,006	14,079
Real estate secured	799,301	785,517
Commercial and industrial	218,757	227,148
Municipal	18,341	21,512
Consumer	9,543	7,687
Unallocated allowance
Totals	1,045,942	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	2,377	2,646
Residential 5+ multifamily	545	686
Construction of residential 1-4 family	95	65
Home equity lines of credit	190	252
Residential real estate	3,207	3,649
Commercial	6,212	6,546
Construction of commercial	668	596
Commercial real estate	6,880	7,142
Farm land	32	59
Vacant land	87	180
Real estate secured	10,206	11,030
Commercial and industrial	1,256	1,397
Municipal	32	43
Consumer	66	77
Unallocated allowance	1,148	1,207
Totals	$ 12,708	$ 13,754

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The fair value as of the balance sheet date of firm holdings in fixed income obligations issued by state and local governments and authorities. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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The net carrying amount as of the balance sheet date of the sum of the various components of an operative builder's inventory, including finished homes. Operative builders primarily consist of entities that develop land, construct residential homes and commercial and industrial buildings thereon, and sell them to home buyers and operators of the commercial and industrial properties.

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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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