Fair Values of Financial Instruments - Schedule of Estimated Fair Values of Recognized Financial Instruments (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial assets
Securities available-for-sale	$ 112,279	$ 112,146
Securities held-to-maturity	10,120	13,950
Equity securities	82	92
Loans held for sale	1,488	622
Bank-owned life insurance	19,284	18,894
Carrying Value [Member]
Financial assets
Cash and cash equivalents	198,144	102,017
Securities available-for-sale	112,279	112,146
Securities held-to-maturity	9,901	13,869
Equity securities	82	92
Restricted stock	4,614	4,614
Loans held for sale	1,488	622
Net loans	619,729	544,616
Bank-owned life insurance	19,284	18,894
Accrued interest receivable	2,022	1,641
Financial liabilities
Deposits	840,656	683,546
Short-term borrowings	41,645	38,889
Other borrowings	9,765	6,330
Accrued interest payable	93	127
Carrying Value [Member] \| Mortgage Servicing Rights [Member]
Financial assets
Mortgage servicing rights	430	328
Fair Value [Member]
Financial assets
Cash and cash equivalents	198,144	102,017
Securities available-for-sale	112,279	112,146
Securities held-to-maturity	10,120	13,950
Equity securities	82	92
Loans held for sale	1,488	622
Net loans	618,607	542,981
Bank-owned life insurance	19,284	18,894
Accrued interest receivable	2,022	1,641
Financial liabilities
Deposits	842,043	683,425
Short-term borrowings	41,645	38,889
Other borrowings	9,896	6,273
Accrued interest payable	93	127
Fair Value [Member] \| Mortgage Servicing Rights [Member]
Financial assets
Mortgage servicing rights	430	328
Fair Value [Member] \| Level I [Member]
Financial assets
Cash and cash equivalents	198,144	102,017
Securities available-for-sale	1,015	999
Equity securities	36	46
Loans held for sale	1,488	622
Bank-owned life insurance	19,284	18,894
Accrued interest receivable	2,022	1,641
Financial liabilities
Deposits	714,920	555,985
Short-term borrowings	41,645	38,889
Accrued interest payable	93	127
Fair Value [Member] \| Level II [Member]
Financial assets
Securities available-for-sale	111,264	111,147
Securities held-to-maturity	10,120	13,950
Fair Value [Member] \| Level III [Member]
Financial assets
Equity securities	46	46
Net loans	618,607	542,981
Financial liabilities
Deposits	127,123	127,440
Other borrowings	9,896	6,273
Fair Value [Member] \| Level III [Member] \| Mortgage Servicing Rights [Member]
Financial assets
Mortgage servicing rights	$ 430	$ 328

Accrued interest payable fair value disclosure.

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Accrued interest receivable fair value disclosure.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The aggregate value of all restricted investments.

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Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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