Fair Values of Assets and Liabilities - Fair Value Measurements, Recurring and Nonrecurring (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financial Assets:
Cash and due from banks	$ 6,643	$ 8,250
Interest-bearing time deposits with other banks		747
Federal Home Loan Bank stock	3,615	3,502
Bank-owned life insurance	4,602	4,561
Loans, net	413,740	398,924
Accrued interest receivable	2,001	1,988
Financial Liabilities:
Deposits	388,941	382,363
Advances from Federal Home Loan Bank	85,597	99,397
Mortgagors’ tax escrow	864	938
Accrued interest payable	227	95
Cash and due from banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	6,643	8,250
Interest-bearing time deposits with other banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure		747
Federal Home Loan Bank stock [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	3,615	3,502
Bank-owned life insurance [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	4,602	4,561
Loans, net [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	369,281	361,402
Accrued interest receivable [member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,001	1,988
Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	386,848	379,714
Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	85,111	97,675
Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	864	938
Accrued interest payable [member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	227	95
Fair Value, Inputs, Level 1 [Member] \| Cash and due from banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	6,643	8,250
Fair Value, Inputs, Level 1 [Member] \| Accrued interest receivable [member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,001	1,988
Fair Value, Inputs, Level 1 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	315,895	320,624
Fair Value, Inputs, Level 1 [Member] \| Accrued interest payable [member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	227	95
Fair Value, Inputs, Level 2 [Member] \| Interest-bearing time deposits with other banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure		747
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank stock [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	3,615	3,502
Fair Value, Inputs, Level 2 [Member] \| Bank-owned life insurance [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	4,602	4,561
Fair Value, Inputs, Level 2 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	70,953	59,090
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	85,111	97,675
Fair Value, Inputs, Level 2 [Member] \| Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	864	938
Fair Value, Inputs, Level 3 [Member] \| Loans, net [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	$ 369,281	$ 361,402

Represents mortgagors tax escrow.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10))
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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 310
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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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