Investment Securities - Summary of Securities Available For Sale By Contractual Maturity (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	$ 104,309	$ 94,997
Fair value due in one year or less	13,230	52,026
Fair value due after one year through five years	65,958	25,574
Fair value	88,064	83,402
Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost due in one year or less	0
Amortized cost due after one year through five years	7,951
Amortized cost due after five years through ten years	25,038
Amortized cost due after ten years	17,787
Amortized cost	104,309
Fair value due in one year or less	0
Fair value due after one year through five years	7,607
Fair value due after five years through ten years	21,381
Fair value due after ten years	13,996
Fair value	88,064
Mortgage-backed securities—U.S. government sponsored enterprises (GSEs) [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	47,917	41,515
Fair value due in one year or less	4,695	15,605
Fair value due after one year through five years	30,434	19,137
Fair value	40,043	34,915
Mortgage-backed securities—U.S. government sponsored enterprises (GSEs) [Member] \| Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	47,917
Fair value	40,043
Small business association (SBA) securities [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,817
Fair value due in one year or less	778
Fair value due after one year through five years	0
Fair value	2,818
Small business association (SBA) securities [Member] \| Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,817
Fair value	2,818
SBIC securities [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,799	2,061
Fair value due in one year or less	0
Fair value due after one year through five years	2,219
Fair value	2,219	$ 2,061
SBIC securities [Member] \| Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,799
Fair value	$ 2,219

Available for sale securities amortized cost and debt maturities fair value.

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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