Earnings Per Share - Calculations of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure Earnings Per Share Calculations Of Basic And Diluted Earnings Per Share [Abstract]
Income (Loss) from Continuing Operations, Per Basic Share	$ 4.75	$ 5.07	$ 4.75
Calculation of Basic Earnings Per Share:
Net Income	$ 87,212	$ 89,796	$ 83,466
Weighted shares outstanding - Basic (in shares)	18,370,758	17,722,227	17,558,078
Basic Earnings Per Share (in usd per share)	$ 4.75	$ 5.07	$ 4.75
Calculation of Diluted Earnings Per Share:
Net Income	$ 87,212	$ 89,796	$ 83,466
Reconciliation of Denominator:
Weighted shares outstanding - Basic (in shares)	18,370,758	17,722,227	17,558,078
Share-based Compensation	64,099	82,067	74,951
Adjusted denominator — Diluted	18,434,857	17,804,294	17,633,029
Income (Loss) from Continuing Operations, Per Diluted Share	$ 4.73	$ 5.04	$ 4.73
Diluted (in usd per share)	$ 4.73	$ 5.04	$ 4.73