Fair Value Measurements - Carrying value and estimated fair value of financial instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Securities:
Available-for-sale, fair value	$ 125,498	$ 130,257
Equity securities, at fair value	3,096	2,832
Restricted securities, at cost	7,637	7,634
Carrying Value
Assets:
Cash and cash equivalents	116,926	122,469
Securities:
Available-for-sale, fair value	125,498	130,257
Held-to-maturity	90,264	92,009
Equity securities, at fair value	3,096	2,832
Restricted securities, at cost	7,637	7,634
Loans, net of allowance	1,897,617	1,853,458
Interest rate swap agreements	287	549
Accrued interest receivable	5,844	5,996
Liabilities:
Time deposits	734,069	709,663
Other deposits	1,162,824	1,182,752
Federal funds purchased	16,500
Federal Home Loan Bank advances	56,000	56,000
Subordinated debt	24,833	24,791
Interest rate swap agreements	287	549
Accrued interest payable	2,280	2,394
Fair Value
Assets:
Cash and cash equivalents	116,926	122,469
Securities:
Available-for-sale, fair value	125,498	130,257
Held-to-maturity	77,448	76,270
Equity securities, at fair value	3,096	2,832
Restricted securities, at cost	7,637	7,634
Loans, net of allowance	1,805,372	1,749,721
Interest rate swap agreements	287	549
Accrued interest receivable	5,844	5,996
Liabilities:
Time deposits	734,885	712,366
Other deposits	1,162,824	1,182,752
Federal funds purchased	16,500
Federal Home Loan Bank advances	56,025	56,000
Subordinated debt	22,452	22,126
Interest rate swap agreements	287	549
Accrued interest payable	2,280	2,394
Fair Value, Inputs, Level 1 \| Fair Value
Assets:
Cash and cash equivalents	116,926	122,469
Securities:
Equity securities, at fair value	3,096	2,832
Liabilities:
Other deposits	1,162,824	1,182,752
Fair Value, Inputs, Level 2 \| Fair Value
Securities:
Available-for-sale, fair value	125,498	130,257
Held-to-maturity	77,448	76,270
Restricted securities, at cost	7,637	7,634
Interest rate swap agreements	287	549
Accrued interest receivable	5,844	5,996
Liabilities:
Time deposits	734,885	712,366
Federal funds purchased	16,500
Federal Home Loan Bank advances	56,025	56,000
Interest rate swap agreements	287	549
Accrued interest payable	2,280	2,394
Fair Value, Inputs, Level 3 \| Fair Value
Securities:
Loans, net of allowance	1,805,372	1,749,721
Liabilities:
Subordinated debt	$ 22,452	$ 22,126

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 deposit liabilities classified as other held by the entity.

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Fair value portion of time deposit liabilities held by the entity.

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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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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).

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

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

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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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