Composition of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Totals	$ 1,066,750	$ 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	370,558	347,695
Residential 5+ multifamily	51,376	36,094
Construction of residential 1-4 family	19,738	8,814
Home equity lines of credit	23,249	27,650
Residential real estate	464,921	420,253
Commercial	307,377	305,193
Construction of commercial	58,838	31,722
Commercial real estate	366,215	336,915
Farm land	2,375	3,040
Vacant land	14,182	13,912
Real estate secured	847,693	774,120
Commercial and industrial	194,856	226,662
Municipal	16,534	21,512
Consumer	12,547	7,661
Unallocated allowance
Totals	1,071,630	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	2,845	2,445
Residential 5+ multifamily	817	686
Construction of residential 1-4 family	186	65
Home equity lines of credit	198	232
Residential real estate	4,046	3,428
Commercial	5,388	6,298
Construction of commercial	1,025	596
Commercial real estate	6,413	6,894
Farm land	21	59
Vacant land	95	178
Real estate secured	10,575	10,559
Commercial and industrial	1,297	1,223
Municipal	31	43
Consumer	82	59
Unallocated allowance	881	1,207
Totals	12,866	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	2,573	4,306
Residential 5+ multifamily	949	964
Construction of residential 1-4 family
Home equity lines of credit	21	154
Residential real estate	3,543	5,424
Commercial	3,546	5,648
Construction of commercial
Commercial real estate	3,546	5,648
Farm land	432	158
Vacant land		167
Real estate secured	7,521	11,397
Commercial and industrial	276	486
Municipal
Consumer		26
Unallocated allowance
Totals	7,797	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	1	201
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit		20
Residential real estate	1	221
Commercial	28	248
Construction of commercial
Commercial real estate	28	248
Farm land
Vacant land		2
Real estate secured	29	471
Commercial and industrial	67	174
Municipal
Consumer		18
Unallocated allowance
Totals	96	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	373,131	352,001
Residential 5+ multifamily	52,325	37,058
Construction of residential 1-4 family	19,738	8,814
Home equity lines of credit	23,270	27,804
Residential real estate	468,464	425,677
Commercial	310,923	310,841
Construction of commercial	58,838	31,722
Commercial real estate	369,761	342,563
Farm land	2,807	3,198
Vacant land	14,182	14,079
Real estate secured	855,214	785,517
Commercial and industrial	195,132	227,148
Municipal	16,534	21,512
Consumer	12,547	7,687
Unallocated allowance
Totals	1,079,427	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	2,846	2,646
Residential 5+ multifamily	817	686
Construction of residential 1-4 family	186	65
Home equity lines of credit	198	252
Residential real estate	4,047	3,649
Commercial	5,416	6,546
Construction of commercial	1,025	596
Commercial real estate	6,441	7,142
Farm land	21	59
Vacant land	95	180
Real estate secured	10,604	11,030
Commercial and industrial	1,364	1,397
Municipal	31	43
Consumer	82	77
Unallocated allowance	881	1,207
Totals	$ 12,962	$ 13,754

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Amount of allowance for credit loss on receivable, classified as other and current.

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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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Represents mortgage loans held in inventory primarily for sale to others (third parties, businesses, legal entities) in the ordinary course of business.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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