composition of loans receivable by risk rating grade (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		$ 368,801	$ 352,001
Residential 5+ multifamily		46,237	37,058
Construction of residential 1-4 family		15,429	8,814
Home equity lines of credit		24,001	27,804
Residential real estate		454,468	425,677
Commercial		314,820	310,841
Construction of commercial		47,145	31,722
Commercial real estate		361,965	342,563
Farm land		3,409	3,198
Vacant land		13,698	14,079
Real estate secured		833,540	785,517
Commercial and industrial		208,180	227,148
Municipal		18,061	21,512
Consumer		11,152	7,687
Loans receivable, gross		1,070,933	1,041,864
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		361,116	342,243
Residential 5+ multifamily		44,484	35,272
Construction of residential 1-4 family		15,301	8,814
Home equity lines of credit		23,706	27,393
Residential real estate		444,607	413,722
Commercial		274,004	276,866
Construction of commercial		47,145	31,493
Commercial real estate		321,149	308,359
Farm land		1,610	1,612
Vacant land		13,621	13,992
Real estate secured		780,987	737,685
Commercial and industrial		205,140	224,906
Municipal		18,061	21,512
Consumer		11,132	7,660
Loans receivable, gross		1,015,320	991,763
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		4,139	5,615
Residential 5+ multifamily		83	90
Construction of residential 1-4 family		128
Home equity lines of credit		209	257
Residential real estate		4,559	5,962
Commercial		5,654	15,565
Construction of commercial
Commercial real estate		5,654	15,565
Farm land		1,223
Vacant land		42	50
Real estate secured		11,478	21,577
Commercial and industrial		500	1,271
Municipal
Consumer		1
Loans receivable, gross		11,979	22,848
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Residential 1-4 family		3,546	4,143
Residential 5+ multifamily		1,670	1,696
Construction of residential 1-4 family
Home equity lines of credit		86	154
Residential real estate		5,302	5,993
Commercial		35,162	18,410
Construction of commercial			229
Commercial real estate		35,162	18,639
Farm land		576	1,586
Vacant land		35	37
Real estate secured		41,075	26,255
Commercial and industrial		2,540	632
Municipal
Consumer		19	27
Loans receivable, gross		43,634	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			339
Municipal
Consumer
Loans receivable, gross			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	368,801
Residential 5+ multifamily	37,058	46,237
Construction of residential 1-4 family	8,814	15,429
Home equity lines of credit	27,804	24,001
Residential real estate	425,677	454,468
Commercial	310,841	314,820
Construction of commercial	31,722	47,145
Commercial real estate	342,563	361,965
Farm land	3,198	3,409
Vacant land	14,079	13,698
Real estate secured	785,517	833,540
Commercial and industrial	227,148	208,180
Municipal	21,512	18,061
Consumer	7,687	11,152
Loans receivable, gross	$ 1,041,864	$ 1,070,933

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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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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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