Fair Value of Financial Instruments - Estimated Fair Values and Related Carrying or Notional Amounts (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets:
Securities - available-for-sale	$ 222,293	$ 168,447
Reported Value Measurement [Member]
Financial Assets:
Cash and cash equivalents	51,296	38,365
Interest-bearing time deposits	4,309	4,019
Securities - available-for-sale	222,293	168,447
Other securities	5,810	3,679
Loans held for sale	4,248	495
Loans, net	1,211,771	839,599
Interest receivable	6,769	4,542
Financial Liabilities:
Total Deposits	1,288,347	928,790
Fed funds purchased and securities sold under agreement to repurchase	48,073	32,181
Federal Home Loan Bank advances	24,806
Interest payable	754	418
Fair Value [Member]
Financial Assets:
Cash and cash equivalents	51,296	38,365
Interest-bearing time deposits	4,331	3,954
Securities - available-for-sale	222,293	168,447
Other securities	5,810	3,679
Loans held for sale	4,248	495
Loans, net	1,188,014	823,914
Interest receivable	6,769	4,542
Financial Liabilities:
Total Deposits	1,288,792	928,922
Fed funds purchased and securities sold under agreement to repurchase	48,073	32,181
Federal Home Loan Bank advances	24,811
Interest payable	754	418
Level 1 [Member]
Financial Assets:
Cash and cash equivalents	51,296	38,365
Securities - available-for-sale	10,021	36,935
Level 2 [Member]
Financial Assets:
Interest-bearing time deposits	4,331	3,954
Securities - available-for-sale	210,782	130,085
Financial Liabilities:
Total Deposits	265,156	215,422
Level 3 [Member]
Financial Assets:
Securities - available-for-sale	1,490	1,427
Other securities	5,810	3,679
Loans held for sale	4,248	495
Loans, net	1,188,014	823,914
Interest receivable	6,769	4,542
Financial Liabilities:
Total Deposits	1,023,636	713,500
Fed funds purchased and securities sold under agreement to repurchase	48,073	32,181
Federal Home Loan Bank advances	24,811
Interest payable	754	418
Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	746,628	525,955
Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	746,628	525,955
Interest Bearing Deposits [Member] \| Level 3 [Member]
Financial Liabilities:
Total Deposits	746,628	525,955
Non Interest Bearing Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	265,156	215,422
Non Interest Bearing Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	265,156	215,422
Non Interest Bearing Deposits [Member] \| Level 2 [Member]
Financial Liabilities:
Total Deposits	265,156	215,422
Time Deposits [Member] \| Reported Value Measurement [Member]
Financial Liabilities:
Total Deposits	276,563	187,413
Time Deposits [Member] \| Fair Value [Member]
Financial Liabilities:
Total Deposits	277,008	187,545
Time Deposits [Member] \| Level 3 [Member]
Financial Liabilities:
Total Deposits	$ 277,008	$ 187,545

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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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