Securities - Reconciliation of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,158,534	$ 768,689
Gross Unrealized Gains	106	5,781
Gross Unrealized Losses	(104,018)	(4,431)
Allowance for Credit Losses	(310)	(83)
Fair Value	1,054,312	769,956
U.S. Treasury and U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	383,958	202,961
Gross Unrealized Gains	100	1,215
Gross Unrealized Losses	(28,419)	(789)
Allowance for Credit Losses	0	0
Fair Value	355,639	203,387
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	351,355	238,456
Gross Unrealized Gains	6	1,250
Gross Unrealized Losses	(40,748)	(1,731)
Allowance for Credit Losses	0	0
Fair Value	310,613	237,975
Collateralized mortgage obligations, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	170,502	191,086
Gross Unrealized Gains	0	1,693
Gross Unrealized Losses	(16,444)	(1,488)
Allowance for Credit Losses	0	0
Fair Value	154,058	191,291
Mortgage-backed securities, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,000	1,816
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(215)	(75)
Allowance for Credit Losses	0	0
Fair Value	785	1,741
Collateralized mortgage obligations, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	51,108	32,254
Gross Unrealized Gains	0	511
Gross Unrealized Losses	(4,775)	(246)
Allowance for Credit Losses	0	0
Fair Value	46,333	32,519
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	54,105	52,518
Gross Unrealized Gains	0	153
Gross Unrealized Losses	(1,710)	(87)
Allowance for Credit Losses	0	0
Fair Value	52,395	52,584
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	22,112
Gross Unrealized Gains	0
Gross Unrealized Losses	(989)
Allowance for Credit Losses	(1)
Fair Value	21,122
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	124,394	49,598
Gross Unrealized Gains	0	959
Gross Unrealized Losses	(10,718)	(15)
Allowance for Credit Losses	(309)	(83)
Fair Value	$ 113,367	$ 50,459

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount, before tax, of unrealized loss 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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-Publisher FASB
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