Premises and Equipment - Summary of Premises and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 15,156	$ 15,148
Less: Accumulated depreciation	9,974	9,697
Premises and equipment, net	5,182	5,451
Land [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	863	863
Building [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	8,074	8,072
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	1	1
Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 6,218	$ 6,212