Investment Securities (Disclosure Regarding Length of Time on Investment Securities with Temporary Impairment) (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Held-to-maturity Securities [Line Items]
Less than 12 months, fair value	$ 107,688	$ 44,820
Less than 12 months, gross unrealized losses	(6,595)	(798)
12 months or longer, fair value	8,482	5,022
12 months or longer, gross unrealized losses	(1,145)	(164)
Total, fair value	116,170	49,842
Total, gross unrealized losses	(7,740)	(962)
Agency obligations
Schedule of Held-to-maturity Securities [Line Items]
Less than 12 months, fair value	9,374	9,821
Less than 12 months, gross unrealized losses	(622)	(175)
12 months or longer, fair value	0	0
12 months or longer, gross unrealized losses	0	0
Total, fair value	9,374	9,821
Total, gross unrealized losses	(622)	(175)
State and municipal obligations
Schedule of Held-to-maturity Securities [Line Items]
Less than 12 months, fair value	90,209	27,350
Less than 12 months, gross unrealized losses	(5,480)	(471)
12 months or longer, fair value	8,482	5,022
12 months or longer, gross unrealized losses	(1,145)	(164)
Total, fair value	98,691	32,372
Total, gross unrealized losses	(6,625)	(635)
Corporate obligations
Schedule of Held-to-maturity Securities [Line Items]
Less than 12 months, fair value	8,105	7,649
Less than 12 months, gross unrealized losses	(493)	(152)
12 months or longer, fair value	0	0
12 months or longer, gross unrealized losses	0	0
Total, fair value	8,105	7,649
Total, gross unrealized losses	$ (493)	$ (152)