Comprehensive Income (Loss) - Schedule of Components of Other Comprehensive Income or Loss and Related Tax Effects Allocated to Each Component (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Before Tax
Net unrealized losses	$ (4,151)	$ (182)
Call and repayment gains charged to investment income	0	(2)
Reclassification adjustment for net realized losses (gains)	429	(1)
Total other comprehensive loss	(3,722)	(185)
Income Tax Effect
Net unrealized losses	(1,047)	(45)
Call and repayment gains charged to investment income	0	0
Reclassification adjustment for realized losses (gains)	109	0
Total other comprehensive loss	(938)	(45)
Net of Tax
Net unrealized losses	(3,104)	(137)
Call and repayment gains charged to investment income	0	(2)
Reclassification adjustment for realized losses (gains)	320	(1)
Total other comprehensive loss, net of income taxes	$ (2,784)	$ (140)