Investment Securities - Proceeds from Sale, Gross Gains (Losses) Realized on Sales, Maturities and Other-Than-Temporary Impairment Charges Related to Securities Available for Sale (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Gain (Loss) on Securities [Line Items]
Proceeds from sale	$ 69,862	$ 69,598	$ 33,756
Gross Losses			(103)
Debt Securities, Realized Gain (Loss), Total	(4,348)	(5,446)	(103)
Calls And Maturities [Member]
Gain (Loss) on Securities [Line Items]
Gross gains	794	89	0
Gross Losses	0	0	0
Debt Securities, Realized Gain (Loss), Total	794	89	0
Sales [Member]
Gain (Loss) on Securities [Line Items]
Gross gains	0	0	0
Gross Losses	5,142	5,535	103
Debt Securities, Realized Gain (Loss), Total	$ 5,142	$ 5,535	$ 103