composition of loans receivable by risk rating grade (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		$ 334,636	$ 342,243
Residential 5+ multifamily		35,919	35,272
Construction of residential 1-4 family		10,435	8,814
Home equity lines of credit		25,756	27,393
Residential real estate		406,746	413,722
Commercial		262,655	276,866
Construction of commercial		34,086	31,493
Commercial real estate		296,741	308,359
Farm land		1,636	1,612
Vacant land		12,344	13,992
Real estate secured		717,467	737,685
Commercial and industrial		246,241	224,906
Municipal		21,495	21,512
Consumer		8,593	7,660
Loans receivable, gross		993,796	991,763
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		5,807	5,615
Residential 5+ multifamily		180	90
Construction of residential 1-4 family
Home equity lines of credit		247	257
Residential real estate		6,234	5,962
Commercial		7,163	15,565
Construction of commercial
Commercial real estate		7,163	15,565
Farm land		1,369
Vacant land		847	50
Real estate secured		15,613	21,577
Commercial and industrial		920	1,271
Municipal
Consumer
Loans receivable, gross		16,533	22,848
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		4,084	4,143
Residential 5+ multifamily		1,690	1,696
Construction of residential 1-4 family
Home equity lines of credit		237	154
Residential real estate		6,011	5,993
Commercial		37,012	18,410
Construction of commercial		226	229
Commercial real estate		37,238	18,639
Farm land		601	1,586
Vacant land		37	37
Real estate secured		43,887	26,255
Commercial and industrial		1,906	632
Municipal
Consumer		24	27
Loans receivable, gross		45,817	26,914
Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate
Commercial
Construction of commercial
Commercial real estate
Farm land
Vacant land
Real estate secured
Commercial and industrial		290	339
Municipal
Consumer
Loans receivable, gross		290	339
Unlikely to be Collected Financing Receivable [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family
Residential 5+ multifamily
Construction of residential 1-4 family
Home equity lines of credit
Residential real estate
Commercial
Construction of commercial
Commercial real estate
Farm land
Vacant land
Real estate secured
Commercial and industrial
Municipal
Consumer
Loans receivable, gross
Nonperforming Financial Instruments [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family	$ 352,001	344,527
Residential 5+ multifamily	37,058	37,789
Construction of residential 1-4 family	8,814	10,435
Home equity lines of credit	27,804	26,240
Residential real estate	425,677	418,991
Commercial	310,841	306,830
Construction of commercial	31,722	34,312
Commercial real estate	342,563	341,142
Farm land	3,198	3,606
Vacant land	14,079	13,228
Real estate secured	785,517	776,967
Commercial and industrial	227,148	249,357
Municipal	21,512	21,495
Consumer	7,687	8,617
Loans receivable, gross	$ 1,041,864	$ 1,056,436

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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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Cost of real estate projects incurred for projects for eventual sale or transfer (condominium or time share projects, vacation clubs).

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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 of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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