Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Earnings Per Share [Abstract]
Net income	$ 15,109	$ 11,401	$ 44,455	$ 55,181
Weighted average shares outstanding - basic (in shares)	5,127,086	5,124,478	5,125,768	5,123,321
Weighted average shares outstanding - diluted (in shares)	5,127,086	5,124,478	5,125,768	5,123,321
Net income per common share - basic (in usd per share)	$ 2.95	$ 2.22	$ 8.67	$ 10.77
Net income per common share - diluted (in usd per share)	$ 2.95	$ 2.22	$ 8.67	$ 10.77