Investment Securities - Summary of Securities Available For Sale By Contractual Maturity (Detail) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	$ 99,102	$ 94,997
Fair value due in one year or less	16,223	52,026
Fair value due after one year through five years	60,475	25,574
Fair value	87,172	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	150
Amortized cost due after one year through five years	4,987
Amortized cost due after five years through ten years	26,903
Amortized cost due after ten years	18,531
Amortized cost	99,102
Fair value due in one year or less	150
Fair value due after one year through five years	4,876
Fair value due after five years through ten years	24,914
Fair value due after ten years	15,779
Fair value	87,172
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	42,035	41,515
Fair value due in one year or less	1,713	15,605
Fair value due after one year through five years	31,480	19,137
Fair value	35,539	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	42,035
Fair value	35,539
Small Business Association (SBA) securities [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	3,362
Fair value	3,363
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	3,362
Fair value	3,363
Subordinated debentures [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	450
Fair value	450
Subordinated debentures [Member] \| Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	450
Fair value	450
SBIC securities [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,684	2,061
Fair value due in one year or less	2,101
Fair value due after one year through five years	0
Fair value	2,101	$ 2,061
SBIC securities [Member] \| Prepayment of Obligation [Member]
Available For Sale Securities Amortized Cost and Debt Maturities Fair Value [Line Items]
Amortized cost	2,684
Fair value	$ 2,101

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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