Investment Securities - Summary of Debt Securities in Unrealized Loss position for Which Allowance for Credit Losses Not Recorded (Detail) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	$ 34,125	$ 61,022
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(551)	(1,215)
Available-for-sale Securities, 12 Months or Longer, Fair Value	63,190	64,629
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(5,761)	(6,464)
Available-for-sale Securities, Fair Value, Total	97,315	125,651
Available-for-sale Securities, Unrealized Losses, Total	(6,312)	(7,679)
US Government Agency securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	3,968	3,960
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(32)	(40)
Available-for-sale Securities, 12 Months or Longer, Fair Value	0	0
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	0	0
Available-for-sale Securities, Fair Value, Total	3,968	3,960
Available-for-sale Securities, Unrealized Losses, Total	(32)	(40)
Obligations of state and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	9,501	11,433
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(204)	(273)
Available-for-sale Securities, 12 Months or Longer, Fair Value	33,890	34,345
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(3,578)	(3,790)
Available-for-sale Securities, Fair Value, Total	43,391	45,778
Available-for-sale Securities, Unrealized Losses, Total	(3,782)	(4,063)
Mortgage-backed securities in government-sponsored entities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	20,656	45,629
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(315)	(902)
Available-for-sale Securities, 12 Months or Longer, Fair Value	28,900	29,877
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(2,175)	(2,665)
Available-for-sale Securities, Fair Value, Total	49,556	75,506
Available-for-sale Securities, Unrealized Losses, Total	(2,490)	(3,567)
Other securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	0	0
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	0	0
Available-for-sale Securities, 12 Months or Longer, Fair Value	400	407
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(8)	(9)
Available-for-sale Securities, Fair Value, Total	400	407
Available-for-sale Securities, Unrealized Losses, Total	$ (8)	$ (9)

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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