Securities - Reconciliation of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 768,689	$ 839,272
Gross Unrealized Gains	5,781	17,806
Gross Unrealized Losses	(4,431)	(1,330)
Allowance for Credit Losses	(83)	(2)
Fair Value	769,956	855,746
U.S. Treasury and U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	202,961	63,868
Gross Unrealized Gains	1,215	1,447
Gross Unrealized Losses	(789)	(313)
Allowance for Credit Losses	0	0
Fair Value	203,387	65,002
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	238,456	224,978
Gross Unrealized Gains	1,250	3,718
Gross Unrealized Losses	(1,731)	(540)
Allowance for Credit Losses	0	0
Fair Value	237,975	228,156
Collateralized mortgage obligations, residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	191,086	204,093
Gross Unrealized Gains	1,693	4,967
Gross Unrealized Losses	(1,488)	(22)
Allowance for Credit Losses	0	0
Fair Value	191,291	209,038
Mortgage-backed securities, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,816	1,944
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(75)	0
Allowance for Credit Losses	0	0
Fair Value	1,741	1,944
Collateralized mortgage obligations, multifamily
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	32,254	39,628
Gross Unrealized Gains	511	1,909
Gross Unrealized Losses	(246)	(2)
Allowance for Credit Losses	0	0
Fair Value	32,519	41,535
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	52,518	40,915
Gross Unrealized Gains	153	0
Gross Unrealized Losses	(87)	(225)
Allowance for Credit Losses	0	0
Fair Value	52,584	40,690
Obligations of states and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		228,790
Gross Unrealized Gains		5,149
Gross Unrealized Losses		(228)
Allowance for Credit Losses		(1)
Fair Value		233,710
Debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	49,598	35,056
Gross Unrealized Gains	959	616
Gross Unrealized Losses	(15)	0
Allowance for Credit Losses	(83)	(1)
Fair Value	$ 50,459	$ 35,671

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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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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