Investment Securities - Summary of Available-For-Sale Securities and Held to Maturity Securities, Continuous Unrealized Loss Position, Fair Value (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	$ 796	$ 39,685
Less than 12 months unrealized losses	(53)	(1,580)
12 months or longer fair value	41,869	4,347
12 months or longer unrealized losses	(1,804)	(360)
Fair value	42,665	44,032
Unrealized losses	(1,857)	(1,940)
Less than 12 months fair value of held to maturity	4,546	46,878
Less than 12 months unrealized losses of held to maturity	(222)	(6,387)
12 months or longer fair value of held to maturity	87,206	46,781
12 months or longer unrealized losses of held to maturity	(11,937)	(5,626)
Fair value of held to maturity	91,752	93,659
Unrealized losses of held to maturity	(12,159)	(12,013)
Mortgage backed securities [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	796	10,920
Less than 12 months unrealized losses	(53)	(537)
12 months or longer fair value	13,009	4,347
12 months or longer unrealized losses	(803)	(360)
Fair value	13,805	15,267
Unrealized losses	(856)	(897)
Less than 12 months fair value of held to maturity	0	32,271
Less than 12 months unrealized losses of held to maturity	0	(5,244)
12 months or longer fair value of held to maturity	49,487	21,445
12 months or longer unrealized losses of held to maturity	(7,163)	(2,403)
Fair value of held to maturity	49,487	53,716
Unrealized losses of held to maturity	(7,163)	(7,647)
Government agencies [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value	0	28,765
Less than 12 months unrealized losses	0	(1,043)
12 months or longer fair value	28,860
12 months or longer unrealized losses	(1,001)
Fair value	28,860	28,765
Unrealized losses	(1,001)	(1,043)
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	2,501	2,456
12 months or longer unrealized losses of held to maturity	(577)	(627)
Fair value of held to maturity	2,501	2,456
Unrealized losses of held to maturity	(577)	(627)
Corporate bonds [Member]
Investments Debt And Equity Securities [Line Items]
Less than 12 months fair value of held to maturity	4,546	14,607
Less than 12 months unrealized losses of held to maturity	(222)	(1,143)
12 months or longer fair value of held to maturity	35,218	22,880
12 months or longer unrealized losses of held to maturity	(4,197)	(2,596)
Fair value of held to maturity	39,764	37,487
Unrealized losses of held to maturity	$ (4,419)	$ (3,739)

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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