Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying or Notional Amounts (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financial Assets:
Securities - available-for-sale	$ 407,500	$ 307,812
Reported Value Measurement [Member]
Financial Assets:
Cash and cash equivalents	151,119	175,706
Interest-bearing time deposits	18,597	4,653
Securities - available-for-sale	407,500	307,812
Other securities	6,419	5,939
Loans held for sale	8,041	7,740
Loans, net	1,443,336	1,289,318
Interest receivable	6,495	6,188
Financial Liabilities:
Total Deposits	1,854,073	1,596,162
Federal funds purchased and securities sold under agreement to repurchase	29,882	30,239
Federal Home Loan Bank advances	17,868	17,861
Interest payable	379	338
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	151,119	175,706
Interest-bearing time deposits	18,635	4,677
Securities - available-for-sale	407,500	307,812
Other securities	6,419	5,939
Loans held for sale	8,041	7,740
Loans, net	1,402,959	1,261,440
Interest receivable	6,495	6,188
Financial Liabilities:
Total Deposits	1,856,014	1,605,890
Federal funds purchased and securities sold under agreement to repurchase	29,882	30,239
Federal Home Loan Bank advances	17,869	17,872
Interest payable	379	338
Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	1,153,765	997,462
Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	1,153,807	1,004,608
Non Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	443,863	351,147
Non Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	443,863	351,147
Time Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	256,445	247,553
Time Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	258,344	250,135
Level 1 [Member]
Financial Assets:
Cash and cash equivalents	151,119	175,706
Securities - available-for-sale	63,360
Level 2 [Member]
Financial Assets:
Interest-bearing time deposits	18,635	4,677
Securities - available-for-sale	340,192	306,250
Financial Liabilities:
Total Deposits	443,863	351,147
Level 2 [Member] \| Non Interest Bearing Deposits [Member]
Financial Liabilities:
Total Deposits	443,863	351,147
Level 3 [Member]
Financial Assets:
Securities - available-for-sale	3,948	1,562
Other securities	6,419	5,939
Loans held for sale	8,041	7,740
Loans, net	1,402,959	1,261,440
Interest receivable	6,495	6,188
Financial Liabilities:
Total Deposits	1,412,151	1,254,743
Federal funds purchased and securities sold under agreement to repurchase	29,882	30,239
Federal Home Loan Bank advances	17,869	17,872
Interest payable	379	338
Level 3 [Member] \| Interest Bearing Deposits [Member]
Financial Liabilities:
Total Deposits	1,153,807	1,004,608
Level 3 [Member] \| Time Deposits [Member]
Financial Liabilities:
Total Deposits	$ 258,344	$ 250,135

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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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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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