Business Combination and Asset Purchase - Schedule of Pro-forma Results (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Summary of Operations
Net Interest Income - Before Provision for Loan Losses	$ 12,777	$ 12,639
Provision for Loan Losses	30	145
Net Interest Income After Provision For Loan Losses	12,747	12,494
Noninterest Income	2,695	2,762
Noninterest Expense	10,224	9,346
Income Before Income Taxes	5,218	5,910
Income Taxes	965	1,108
Net Income	$ 4,253	$ 4,802
Basic and Diluted Earnings Per Share	$ 0.38	$ 0.43