Investment Securities - Summary of Debt Securities in Unrealized Loss position for Which Allowance for Credit Losses Not Recorded (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	$ 39,610	$ 11,534
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(531)	(388)
Available-for-sale Securities, 12 Months or Longer, Fair Value	60,320	59,586
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(6,298)	(5,774)
Available-for-sale Securities, Fair Value, Total	99,930	71,120
Available-for-sale Securities, Unrealized Losses, Total	(6,829)	(6,162)
US Government Agency securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	0	1,995
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	0	(5)
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	0	1,995
Available-for-sale Securities, Unrealized Losses, Total	0	(5)
US Government Treasury securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	0
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	0
Available-for-sale Securities, 12 Months or Longer, Fair Value	0
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	0
Available-for-sale Securities, Fair Value, Total	0
Available-for-sale Securities, Unrealized Losses, Total	0
Obligations of state and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	13,306	4,836
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(325)	(247)
Available-for-sale Securities, 12 Months or Longer, Fair Value	28,394	27,736
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(2,994)	(2,768)
Available-for-sale Securities, Fair Value, Total	41,700	32,572
Available-for-sale Securities, Unrealized Losses, Total	(3,319)	(3,015)
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	24,632	4,703
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(197)	(136)
Available-for-sale Securities, 12 Months or Longer, Fair Value	31,369	31,249
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(3,292)	(2,993)
Available-for-sale Securities, Fair Value, Total	56,001	35,952
Available-for-sale Securities, Unrealized Losses, Total	(3,489)	(3,129)
Other securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale Securities, Less than 12 Months, Fair Value	1,672	0
Available-for-sale Securities, Less than 12 Months, Unrealized Losses	(9)	0
Available-for-sale Securities, 12 Months or Longer, Fair Value	557	601
Available-for-sale Securities, 12 Months or Longer, Unrealized Losses	(12)	(13)
Available-for-sale Securities, Fair Value, Total	2,229	601
Available-for-sale Securities, Unrealized Losses, Total	$ (21)	$ (13)

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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