Earnings per Common Share - Computation of Basic and Diluted Earnings per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Basic
Net income	$ 42,964	$ 39,427	$ 40,546
Less allocation of earnings and dividends to participating securities	1,583	498	173
Net income available to common shareholders-basic	$ 41,381	$ 38,929	$ 40,373
Weighted average common shares outstanding	15,734,624	15,162,032	15,408,863
Less average participating securities	579,857	191,402	65,648
Weighted average common shares outstanding for earnings per common share basic	15,154,767	14,970,630	15,343,215
Basic earnings per share	$ 2.73	$ 2.6	$ 2.63
Diluted
Net income available to common shareholders-diluted	$ 41,381	$ 38,929	$ 40,373
Weighted average number of shares outstanding used in the calculation of basic earnings per common share	15,154,767	14,970,630	15,343,215
Average shares and dilutive potential common shares outstanding—diluted	15,154,767	14,970,630	15,343,215
Diluted earnings per share	$ 2.73	$ 2.6	$ 2.63