Investment Securities - Summary of Available-For-Sale Securities and Held to Maturity Securities, Continuous Unrealized Loss Position, Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	$ 0	$ 0
Less than 12 months unrealized losses	0	0
12 months or longer fair value	29,338	42,725
12 months or longer unrealized losses	(1,173)	(1,263)
Fair value	29,338	42,725
Unrealized losses	(1,173)	(1,263)
Less than 12 months fair value of held to maturity	0	0
Less than 12 months unrealized losses of held to maturity	0	0
12 months or longer fair value of held to maturity	81,472	90,030
12 months or longer unrealized losses of held to maturity	(11,203)	(10,811)
Fair value of held to maturity	81,472	90,030
Unrealized losses of held to maturity	(11,203)	(10,811)
Mortgage backed securities [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	0	0
Less than 12 months unrealized losses	0	0
12 months or longer fair value	9,783	13,314
12 months or longer unrealized losses	(787)	(758)
Fair value	9,783	13,314
Unrealized losses	(787)	(758)
Less than 12 months fair value of held to maturity	0	0
Less than 12 months unrealized losses of held to maturity	0	0
12 months or longer fair value of held to maturity	42,113	50,788
12 months or longer unrealized losses of held to maturity	(6,718)	(6,140)
Fair value of held to maturity	42,113	50,788
Unrealized losses of held to maturity	(6,718)	(6,140)
Government agencies [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	0	0
Less than 12 months unrealized losses	0	0
12 months or longer fair value	19,555	29,411
12 months or longer unrealized losses	(386)	(505)
Fair value	19,555	29,411
Unrealized losses	(386)	(505)
Less than 12 months fair value of held to maturity	0	0
Less than 12 months unrealized losses of held to maturity	0	0
12 months or longer fair value of held to maturity	2,563	2,559
12 months or longer unrealized losses of held to maturity	(507)	(513)
Fair value of held to maturity	2,563	2,559
Unrealized losses of held to maturity	(507)	(513)
Corporate bonds [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value of held to maturity	0	0
Less than 12 months unrealized losses of held to maturity	0	0
12 months or longer fair value of held to maturity	36,795	36,683
12 months or longer unrealized losses of held to maturity	(3,978)	(4,158)
Fair value of held to maturity	36,795	36,683
Unrealized losses of held to maturity	$ (3,978)	$ (4,158)

Investments debt and equity securities.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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