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Fair Values of Assets and Liabilities - Summary of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2023		Dec. 31, 2022
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 109,896		$ 106,100
U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,840		1,826
U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,788	[1]	8,359
Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,864	[1]	6,222
Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	21,672	[1]	21,823
Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	65,141		62,416
Corporate debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	485		497
Corporate subordinated debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,106		4,957
Fair Value, Measurements, Recurring [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,840		1,826
Fair Value, Measurements, Recurring [Member] | U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,788		8,359
Fair Value, Measurements, Recurring [Member] | Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,864		6,222
Fair Value, Measurements, Recurring [Member] | Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	21,672		21,823
Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	65,141		62,416
Fair Value, Measurements, Recurring [Member] | Corporate debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	485		497
Fair Value, Measurements, Recurring [Member] | Corporate subordinated debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,106		4,957
Fair Value, Measurements, Recurring [Member] | Derivative [Member]
Other assets:
Other assets, at fair value	326		961
Other liabilities:
Other liabilities, at fair value	48
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,840		1,826
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government agency small business administration pools guaranteed by SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,788		8,359
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	5,864		6,222
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	21,672		21,823
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	65,141		62,416
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	485		497
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Corporate subordinated debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,106		4,957
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member]
Other assets:
Other assets, at fair value	326		961
Other liabilities:
Other liabilities, at fair value	48
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member]
Other assets:
Other assets, at fair value	350		357
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member] | Fair Value, Inputs, Level 3 [Member]
Other assets:
Other assets, at fair value	$ 350		$ 357
[1] Actual maturities for these debt securities are dependent upon the interest rate environment and prepayments on the underlying loans.

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