Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying or Notional Amounts (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial Assets:
Securities - available-for-sale	$ 404,881	$ 358,478
Financial Liabilities:
Subordinated notes, net of unamortized issuance costs	34,789	34,702
Dividend payable	2,998	2,974
Reported Value Measurement [Member]
Financial Assets:
Cash and cash equivalents	245,504	142,201
Interest-bearing time deposits	2,727	2,740
Securities - available-for-sale	404,881	358,478
Other securities	15,028	17,138
Loans held for sale	1,706	1,576
Loans, net	2,512,852	2,556,167
Interest receivable	14,316	11,774
Financial Liabilities:
Total Deposits	2,684,813	2,607,463
Federal funds purchased and securities sold under agreement to repurchase	27,292	28,218
Federal Home Loan Bank advances	263,081	265,750
Subordinated notes, net of unamortized issuance costs	34,789	34,702
Interest payable	6,527	5,441
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	245,504	142,201
Interest-bearing time deposits	2,742	2,725
Securities - available-for-sale	404,881	358,478
Other securities	15,028	17,138
Loans held for sale	1,706	1,552
Loans, net	2,454,546	2,396,540
Interest receivable	14,316	11,774
Financial Liabilities:
Total Deposits	2,684,204	2,600,613
Federal funds purchased and securities sold under agreement to repurchase	27,292	28,218
Federal Home Loan Bank advances	249,109	260,400
Subordinated notes, net of unamortized issuance costs	30,642	30,676
Interest payable	6,527	5,441
Level 1 [Member]
Financial Assets:
Cash and cash equivalents	245,504	142,201
Securities - available-for-sale	125,396	99,900
Financial Liabilities:
Total Deposits	481,444	528,465
Level 2 [Member]
Financial Assets:
Interest-bearing time deposits	2,742	2,725
Securities - available-for-sale	277,839	256,118
Financial Liabilities:
Subordinated notes, net of unamortized issuance costs	30,642	30,676
Level 3 [Member]
Financial Assets:
Securities - available-for-sale	1,646	2,460
Other securities	15,028	17,138
Loans held for sale	1,706	1,552
Loans, net	2,454,546	2,396,540
Interest receivable	14,316	11,774
Financial Liabilities:
Total Deposits	2,202,760	2,072,148
Federal funds purchased and securities sold under agreement to repurchase	27,292	28,218
Federal Home Loan Bank advances	249,109	260,400
Interest payable	6,527	5,441
Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	1,527,182	1,415,981
Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	1,526,588	1,416,007
Interest Bearing Deposits [Member] \| Level 3 [Member]
Financial Liabilities:
Total Deposits	1,526,588	1,416,007
Non Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	481,444	528,465
Non Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	481,444	528,465
Non Interest Bearing Deposits [Member] \| Level 1 [Member]
Financial Liabilities:
Total Deposits	481,444	528,465
Time Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	676,187	663,017
Time Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	676,172	656,141
Time Deposits [Member] \| Level 3 [Member]
Financial Liabilities:
Total Deposits	$ 676,172	$ 656,141

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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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