Fair Values of Assets and Liabilities - Fair Value Measurements, Recurring and Nonrecurring (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financial Assets:
Cash and due from banks	$ 6,638	$ 5,996
Interest-bearing time deposits with other banks	1,245	2,488
Federal Home Loan Bank stock	1,688	1,796
Bank-owned life insurance	4,461	4,356
Loans, net	373,051	364,800
Accrued interest receivable	1,499	1,412
Financial Liabilities:
Deposits	393,243	327,381
Advances from Federal Home Loan Bank	29,462	34,127
Mortgagors’ tax escrow	652	1,420
Advances from Federal Reserve Bank		18,195
Cash and due from banks [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	6,638	5,996
Interest-bearing time deposits with other banks [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,245	2,488
Federal Home Loan Bank stock [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,688	1,796
Bank-owned life insurance [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	4,461	4,356
Loans, net [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	371,587	365,116
Accrued interest receivable [member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,499	1,412
Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	393,145	327,696
Financial Liabilities Fair Value Disclosure	393,145	327,696
Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	29,063	34,832
Financial Liabilities Fair Value Disclosure	29,063	34,832
Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	652	1,420
Financial Liabilities Fair Value Disclosure	652	1,420
FRB [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure		18,199
Financial Liabilities Fair Value Disclosure		18,199
Fair Value, Inputs, Level 1 [Member] \| Cash and due from banks [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	6,638	5,996
Fair Value, Inputs, Level 1 [Member] \| Accrued interest receivable [member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,499	1,412
Fair Value, Inputs, Level 1 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	334,917	278,713
Financial Liabilities Fair Value Disclosure	334,917	278,713
Fair Value, Inputs, Level 2 [Member] \| Interest-bearing time deposits with other banks [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,245	2,488
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank stock [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	1,688	1,796
Fair Value, Inputs, Level 2 [Member] \| Bank-owned life insurance [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	4,461	4,356
Fair Value, Inputs, Level 2 [Member] \| Deposits [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	58,228	48,983
Financial Liabilities Fair Value Disclosure	58,228	48,983
Fair Value, Inputs, Level 2 [Member] \| Federal Home Loan Bank Borrowings [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	29,063	34,832
Financial Liabilities Fair Value Disclosure	29,063	34,832
Fair Value, Inputs, Level 2 [Member] \| Mortgagors' tax escrow [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure	652	1,420
Financial Liabilities Fair Value Disclosure	652	1,420
Fair Value, Inputs, Level 2 [Member] \| FRB [Member]
Financial Liabilities:
Financial Liabilities Fair Value Disclosure		18,199
Financial Liabilities Fair Value Disclosure		18,199
Fair Value, Inputs, Level 3 [Member] \| Loans, net [Member]
Assets, Fair Value Disclosure
Assets, Fair Value Disclosure	$ 371,587	$ 365,116

Advances from federal reserve bank.

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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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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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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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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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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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