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Investment Securities - Reconciliation of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,183,587		$ 768,689
Gross Unrealized Gains	120		5,781
Gross Unrealized Losses	(105,529)		(4,431)
Allowance for Credit Losses	(4,165)	$ (2,802)	(83)	$ (50)	$ (21)	$ (2)
Total	1,074,013		769,956
U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	387,049		202,961
Gross Unrealized Gains	116		1,215
Gross Unrealized Losses	(29,316)		(789)
Allowance for Credit Losses	0		0
Total	357,849		203,387
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	360,191		238,456
Gross Unrealized Gains	4		1,250
Gross Unrealized Losses	(45,850)		(1,731)
Allowance for Credit Losses	0		0
Total	314,345		237,975
Collateralized mortgage obligations, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	177,032		191,086
Gross Unrealized Gains	0		1,693
Gross Unrealized Losses	(15,808)		(1,488)
Allowance for Credit Losses	0		0
Total	161,224		191,291
Mortgage-backed securities, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,006		1,816
Gross Unrealized Gains	0		0
Gross Unrealized Losses	(221)		(75)
Allowance for Credit Losses	0		0
Total	785		1,741
Collateralized mortgage obligations, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	51,711		32,254
Gross Unrealized Gains	0		511
Gross Unrealized Losses	(4,987)		(246)
Allowance for Credit Losses	0		0
Total	46,724		32,519
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	59,131		52,518
Gross Unrealized Gains	0		153
Gross Unrealized Losses	(1,588)		(87)
Allowance for Credit Losses	0		0
Total	57,543		52,584
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	23,024
Gross Unrealized Gains	0
Gross Unrealized Losses	(1,504)
Allowance for Credit Losses	(1)
Total	21,519
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	124,443		49,598
Gross Unrealized Gains	0		959
Gross Unrealized Losses	(6,255)		(15)
Allowance for Credit Losses	(4,164)		(83)
Total	$ 114,024		$ 50,459