Fair Values of Assets and Liabilities - Fair Value Measurements, Recurring and Nonrecurring (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financial Assets:
Cash and due from banks	$ 19,573	$ 7,100
Federal Home Loan Bank stock	2,431	2,498
Bank-owned life insurance	4,854	4,768
Loans, net	430,027	435,481
Accrued interest receivable	2,179	2,103
Financial Liabilities:
Deposits	480,033	454,208
Advances from Federal Home Loan Bank	51,748	52,268
Mortgagors’ tax escrow	2,112	654
Accrued interest payable	480	475
Cash and due from banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	19,573	7,100
Federal Home Loan Bank stock [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,431	2,498
Bank-owned life insurance [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	4,854	4,768
Loans, net [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	398,116	397,154
Accrued interest receivable [member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,179	2,103
Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	480,162	453,890
Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	51,762	52,208
Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	2,112	654
Accrued interest payable [member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	480	475
Fair Value, Inputs, Level 1 [Member] \| Cash and due from banks [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	19,573	7,100
Fair Value, Inputs, Level 1 [Member] \| Accrued interest receivable [member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,179	2,103
Fair Value, Inputs, Level 1 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	323,173	318,520
Fair Value, Inputs, Level 1 [Member] \| Accrued interest payable [member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	480	475
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank stock [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	2,431	2,498
Fair Value, Inputs, Level 2 [Member] \| Bank-owned life insurance [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	4,854	4,768
Fair Value, Inputs, Level 2 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	156,989	135,370
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	51,762	52,208
Fair Value, Inputs, Level 2 [Member] \| Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	2,112	654
Fair Value, Inputs, Level 3 [Member] \| Loans, net [Member]
Financial Assets:
Financial Assets, Fair Value Disclosure	$ 398,116	$ 397,154

Represents mortgagors tax escrow.

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Fair value portion of asset recognized for present right to economic benefit.

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- Definition

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.

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

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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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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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