Securities - Reconciliation of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,035,238	$ 1,158,534
Gross Unrealized Gains	115	106
Gross Unrealized Losses	(89,071)	(104,018)
Allowance for Credit Losses	0	(310)	$ (83)
Fair Value	946,282	1,054,312
U.S. Treasury and U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	339,364	383,958
Gross Unrealized Gains	99	100
Gross Unrealized Losses	(19,694)	(28,419)
Allowance for Credit Losses	0	0
Fair Value	319,769	355,639
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	320,947	351,355
Gross Unrealized Gains	16	6
Gross Unrealized Losses	(34,546)	(40,748)
Allowance for Credit Losses	0	0
Fair Value	286,417	310,613
Collateralized mortgage obligations, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	150,726	170,502
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(13,656)	(16,444)
Allowance for Credit Losses	0	0
Fair Value	137,070	154,058
Mortgage-backed securities, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	856	1,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(180)	(215)
Allowance for Credit Losses	0	0
Fair Value	676	785
Collateralized mortgage obligations, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	46,541	51,108
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(4,045)	(4,775)
Allowance for Credit Losses	0	0
Fair Value	42,496	46,333
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	44,561	54,105
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(868)	(1,710)
Allowance for Credit Losses	0	0
Fair Value	43,693	52,395
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	19,699	22,112
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(571)	(989)
Allowance for Credit Losses	0	(1)
Fair Value	19,128	21,122
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	112,544	124,394
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(15,511)	(10,718)
Allowance for Credit Losses	0	(309)
Fair Value	$ 97,033	$ 113,367

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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