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Employee Benefit Plans - Additional Information (Detail) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 USD ($) Employee shares | Dec. 31, 2022 USD ($) Employee shares | Dec. 31, 2021 USD ($) Employee shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Minimum percentage of eligible compensation on a pre-tax or post-tax basis for eligible employees to save | 1.00% |  |
Employee contribution matching percentage | 50.00% |  |
Percentage of total eligible compensation, contribution by Bank, maximum limit | 6.00% |  |
Vesting percentage in participant's deferral contributions and employer matching contributions | 100.00% |  |
Nonelective employer contribution vesting percentage | 100.00% |  |
Defined contribution plan employer matching contribution description | In order to be eligible for discretionary contributions, employees must work 1,000 hours in the plan year and be employed on the last day of the year. |  |
Employer matching contribution and the discretionary contribution | $ | $ 1,400 | $ 1,700 | $ 1,500
Restricted stock awards, shares issued | 64,225 | 56,496 | 48,750
Awards grants originated in 2019, 2020 and 2021 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of employees, received the stock | Employee |  | 3 |
Number of shares vested |  | 3,775 |
Awards grants originated in 2018, 2019 and 2020 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of employees, received the stock | Employee |  |  | 7
Number of shares vested |  |  | 4,425
Awards grants originated in 2020, 2021 and 2022 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of employees, received the stock | Employee | 4 |  |
Number of shares vested | 2,350 |  |
Restricted Stock Awards [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting period | 3 years |  |
Restricted stock awards, shares issued | 64,225 | 56,496 | 48,750
Stock issued to number of employees | Employee | 113 | 109 | 96
Shares vest under the plan | 100.00% | 100.00% | 100.00%
Shares forfeited due to employee termination | 6,350 | 8,000 | 2,575
Number of shares vested | 35,477 | 30,675 | 23,270
Number of employees, received the stock | Employee | 69 | 60 | 50
Number of shares vested | 2,350 | 3,775 | 4,425
Compensation expense | $ | $ 1,300 | $ 899 | $ 822
Unrecognized compensation cost related to the nonvested portion of restricted stock awards under the plan | $ | $ 2,100 |  |
Unrecognized compensation cost related to the nonvested portion of restricted stock awards under the plan, period for recognition | 3 years |  |
Restricted Stock Awards [Member] | 2022 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares vested | 2,996 |  |
Number of employees, received the stock | Employee | 4 |  |
Restricted Stock Awards [Member] | 2020 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares vested | 29,431 |  |
Number of employees, received the stock | Employee | 65 |  |
Restricted Stock Awards [Member] | 2019 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares vested |  | 26,900 |
Number of employees, received the stock | Employee |  | 60 |
Restricted Stock Awards [Member] | 2018 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares vested |  |  | 18,845
Number of employees, received the stock | Employee |  |  | 50
Restricted Stock Awards [Member] | Awards grants originated in 2020 [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of shares vested | 700 |  |
Number of employees, received the stock | Employee | 1 |  |

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