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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