Earnings Per Share - Schedule of Earnings Per Share, Basic and Diluted (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Earnings Per Share [Abstract]
Net income	$ 14,814	$ 25,898	$ 29,346	$ 43,780
Weighted average shares outstanding - basic (in shares)	5,125,710	5,123,255	5,125,098	5,122,733
Weighted average shares outstanding - diluted (in shares)	5,125,710	5,123,255	5,125,098	5,122,733
Net income per common share - basic (in usd per share)	$ 2.89	$ 5.05	$ 5.73	$ 8.55
Net income per common share - diluted (in usd per share)	$ 2.89	$ 5.05	$ 5.73	$ 8.55