Other Comprehensive Income (Loss) - Components of Other Comprehensive Income (loss) Pre-Tax and After-Tax (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
After-tax
Other comprehensive income (loss)	$ (2,542)	$ 13,791
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent
Pre-tax
Unrealized holding gains (losses) arising during the period	(3,442)	17,593
Less: Reclassification adjustments for (gains) losses realized in net income (loss)	69	701
Other comprehensive income (loss)	(3,373)	18,294
Tax
Unrealized holding gains (losses) arising during the period	(848)	4,330
Less: Reclassification adjustments for (gains) losses realized in net income (loss)	17	173
Other comprehensive income (loss)	(831)	4,503
After-tax
Unrealized holding gains (losses) arising during the period	(2,594)	13,263
Less: Reclassification adjustments for (gains) losses realized in net income (loss)	52	528
Other comprehensive income (loss)	$ (2,542)	$ 13,791

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