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Employee Benefit Plans - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) Employee shares	Dec. 31, 2021 USD ($) Employee shares	Dec. 31, 2020 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 | $	$ 1,700	$ 1,500	$ 1,000
Restricted stock awards, shares issued	56,496	48,750	37,382
Awards grants originated in 2019, 2018 and 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees, received the stock | Employee			1
Number of shares vested			1,050
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 2017, 2018, 2019 and 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees, received the stock | Employee			8
Four employees received shares from awards granted due to retirement			10,890
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
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Restricted stock awards, shares issued	56,496	48,750	37,382
Stock issued to number of employees | Employee	109	96	92
Shares vest under the plan	100.00%	100.00%	100.00%
Shares forfeited due to employee termination	8,000	2,575	2,175
Number of shares vested	30,675	23,270	35,431
Number of employees, received the stock | Employee	60	50	58
Number of shares vested	3,775	4,425	10,890
Compensation expense | $	$ 899	$ 822	$ 1,000
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] | 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] | 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested	26,900		1,600
Number of employees, received the stock | Employee	60
Restricted Stock Awards [Member] | 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested			21,340
Number of employees, received the stock | Employee			53
Restricted Stock Awards [Member] | Immediate Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees, received the stock | Employee			1
Number of shares vested			551

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