Composition of loans receivable and the allowance for loan losses (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Residential 1-4 family	$ 414,957	$ 373,131
Residential 5+ multifamily	70,459	52,325
Construction of residential 1-4 family	21,527	19,738
Home equity lines of credit	24,895	23,270
Residential real estate	531,838	468,464
Commercial	367,257	310,923
Construction of commercial	45,762	58,838
Commercial real estate	413,019	369,761
Farm land	4,225	2,807
Vacant land	14,796	14,182
Real estate secured	963,878	855,214
Commercial and industrial	186,996	195,132
Municipal	18,607	16,534
Consumer	20,344	12,547
Totals	1,176,493	1,066,750
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	413,456	370,558
Residential 5+ multifamily	70,380	51,376
Construction of residential 1-4 family	21,527	19,738
Home equity lines of credit	24,895	23,249
Residential real estate	530,258	464,921
Commercial	364,729	307,377
Construction of commercial	45,762	58,838
Commercial real estate	410,491	366,215
Farm land	3,828	2,375
Vacant land	14,796	14,182
Real estate secured	959,373	847,694
Commercial and industrial	186,969	194,856
Municipal	18,607	16,534
Consumer	20,344	12,547
Unallocated allowance
Totals	1,185,293	1,071,630
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	3,393	2,845
Residential 5+ multifamily	1,228	817
Construction of residential 1-4 family	205	186
Home equity lines of credit	219	198
Residential real estate	5,045	4,046
Commercial	5,745	5,388
Construction of commercial	757	1,025
Commercial real estate	6,502	6,413
Farm land	38	21
Vacant land	112	95
Real estate secured	11,697	10,575
Commercial and industrial	1,485	1,297
Municipal	39	31
Consumer	122	82
Unallocated allowance	969	881
Totals	14,312	12,866
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	1,501	2,573
Residential 5+ multifamily	79	949
Construction of residential 1-4 family
Home equity lines of credit		21
Residential real estate	1,580	3,543
Commercial	2,528	3,546
Construction of commercial
Commercial real estate	2,528	3,546
Farm land	397	432
Vacant land
Real estate secured	4,505	7,520
Commercial and industrial	27	276
Municipal
Consumer
Unallocated allowance
Totals	4,532	7,797
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
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate		1
Commercial	22	28
Construction of commercial
Commercial real estate	22	28
Farm land
Vacant land
Real estate secured	22	29
Commercial and industrial		67
Municipal
Consumer
Unallocated allowance
Totals	22	96
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	414,957	373,131
Residential 5+ multifamily	70,459	52,325
Construction of residential 1-4 family	21,527	19,738
Home equity lines of credit	24,895	23,270
Residential real estate	531,838	468,464
Commercial	367,257	310,923
Construction of commercial	45,762	58,838
Commercial real estate	413,019	369,761
Farm land	4,225	2,807
Vacant land	14,796	14,182
Real estate secured	963,878	855,214
Commercial and industrial	186,996	195,132
Municipal	18,607	16,534
Consumer	20,344	12,547
Unallocated allowance
Totals	1,189,825	1,079,427
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	3,393	2,846
Residential 5+ multifamily	1,228	817
Construction of residential 1-4 family	205	186
Home equity lines of credit	219	198
Residential real estate	5,045	4,047
Commercial	5,767	5,416
Construction of commercial	757	1,025
Commercial real estate	6,524	6,441
Farm land	38	21
Vacant land	112	95
Real estate secured	11,719	10,604
Commercial and industrial	1,485	1,364
Municipal	39	31
Consumer	122	82
Unallocated allowance	969	881
Totals	$ 14,334	$ 12,962

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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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