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Investment Securities - Reconciliation of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,209,588		$ 768,689
Gross Unrealized Gains	248		5,781
Gross Unrealized Losses	(67,620)		(4,431)
Allowance for Credit Losses	(2,802)	$ (1,267)	(83)	$ (21)	$ (144)	$ (2)
Total	1,139,414		769,956
U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	389,836		202,961
Gross Unrealized Gains	138		1,215
Gross Unrealized Losses	(19,923)		(789)
Allowance for Credit Losses	0		0
Total	370,051		203,387
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	370,700		238,456
Gross Unrealized Gains	8		1,250
Gross Unrealized Losses	(30,371)		(1,731)
Allowance for Credit Losses	0		0
Total	340,337		237,975
Collateralized mortgage obligations, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	181,946		191,086
Gross Unrealized Gains	2		1,693
Gross Unrealized Losses	(9,641)		(1,488)
Allowance for Credit Losses	0		0
Total	172,307		191,291
Mortgage-backed securities, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,804		1,816
Gross Unrealized Gains	0		0
Gross Unrealized Losses	(299)		(75)
Allowance for Credit Losses	0		0
Total	1,505		1,741
Collateralized mortgage obligations, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	52,779		32,254
Gross Unrealized Gains	0		511
Gross Unrealized Losses	(3,159)		(246)
Allowance for Credit Losses	0		0
Total	49,620		32,519
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	61,587		52,518
Gross Unrealized Gains	1		153
Gross Unrealized Losses	(1,726)		(87)
Allowance for Credit Losses	0		0
Total	59,862		52,584
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	23,930
Gross Unrealized Gains	0
Gross Unrealized Losses	(903)
Allowance for Credit Losses	(2)
Total	23,025
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	127,006		49,598
Gross Unrealized Gains	99		959
Gross Unrealized Losses	(1,598)		(15)
Allowance for Credit Losses	(2,800)		(83)
Total	$ 122,707		$ 50,459