Investment Securities - Summary of Amortized Cost and Estimated Market Value of Investment Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Available-for-sale Securities, Debt Maturities [Abstract]
Amortized Cost, due in one year or less	$ 2,395
Amortized Cost, due after one year through five years	7,313
Amortized Cost, due after five years through ten years	8,833
Amortized Cost, due after ten years	42,032
Amortized Cost	60,573	$ 54,301
Fair Value, due in one year or less	2,336
Fair Value, due after one year through five years	7,049
Fair Value, due after five years through ten years	7,808
Fair Value, due after ten years	37,089
Fair Value	$ 54,282	$ 48,492