Bank Premises and Equipment - Summary of Bank Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Bank premises and equipment, gross	$ 29,193	$ 22,920
Less accumulated depreciation	(10,782)	(9,925)
Bank premises and equipment excluding land, gross	18,411	12,995
Land	4,258	2,551
Bank premises and equipment, net	22,669	15,546
Land Improvements [Member]
Property Plant And Equipment [Line Items]
Bank premises and equipment, gross	783	710
Buildings [Member]
Property Plant And Equipment [Line Items]
Bank premises and equipment, gross	20,213	14,983
Equipment, Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Bank premises and equipment, gross	8,154	7,151
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Bank premises and equipment, gross	$ 43	$ 76