Fair Value Measurements - Carrying value and estimated fair value of financial instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Securities:
Equity securities, at fair value	$ 2,590	$ 2,115
Restricted securities, at cost	4,529	4,425
Carrying Value
Assets:
Cash and cash equivalents	103,359	61,599
Securities:
Available-for-sale	340,159	357,576
Held-to-maturity	98,507	99,415
Equity securities, at fair value	2,590	2,115
Restricted securities, at cost	4,529	4,425
Loans, net	1,749,653	1,769,300
Derivative assets, at fair value	1,038	1,217
Bank owned life insurance	21,270	21,170
Accrued interest receivable	5,471	5,531
Liabilities:
Deposits	2,088,642	2,067,740
Subordinated debt	24,645	24,624
Federal funds purchased		25,500
Derivative liabilities, at fair value	1,038	1,217
Accrued interest payable	972	1,035
Fair Value
Assets:
Cash and cash equivalents	103,359	61,599
Securities:
Available-for-sale	340,159	357,576
Held-to-maturity	81,966	81,161
Equity securities, at fair value	2,590	2,115
Restricted securities, at cost	4,529	4,425
Loans, net	1,660,163	1,676,887
Derivative assets, at fair value	1,038	1,217
Bank owned life insurance	21,270	21,170
Accrued interest receivable	5,471	5,531
Liabilities:
Deposits	2,085,334	2,065,248
Subordinated debt	22,152	22,457
Federal funds purchased		25,500
Derivative liabilities, at fair value	1,038	1,217
Accrued interest payable	972	1,035
Fair Value, Inputs, Level 1 \| Fair Value
Assets:
Cash and cash equivalents	103,359	61,599
Securities:
Equity securities, at fair value	2,590	2,115
Fair Value, Inputs, Level 2 \| Fair Value
Securities:
Available-for-sale	340,159	357,576
Held-to-maturity	81,966	81,161
Restricted securities, at cost	4,529	4,425
Derivative assets, at fair value	1,038	1,217
Bank owned life insurance	21,270	21,170
Accrued interest receivable	5,471	5,531
Liabilities:
Deposits	2,085,334	2,065,248
Federal funds purchased		25,500
Derivative liabilities, at fair value	1,038	1,217
Accrued interest payable	972	1,035
Fair Value, Inputs, Level 3 \| Fair Value
Securities:
Loans, net	1,660,163	1,676,887
Liabilities:
Subordinated debt	$ 22,152	$ 22,457

Fair value portion of the accrued interest payable.

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Fair value portion of the accrued interest receivable.

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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 the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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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 of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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Fair value portion of federal funds sold and securities borrowed or purchased under agreements to resell.

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

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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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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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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