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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, 2025		Dec. 31, 2024
Securities available-for-sale:
Securities available-for-sale, at fair value	$ 144,282		$ 120,217
U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,438		1,387
U.S. Government agency small business administration pools guaranteed by the SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	11,901	[1]	13,125
Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	35,906	[1]	19,362
Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	58,907	[1]	48,462
Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	27,740		29,532
Corporate debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	487		484
Corporate subordinated debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,903		7,865
Fair Value, Measurements, Recurring [Member] | U.S. Government-sponsored enterprises obligations [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	1,438		1,387
Fair Value, Measurements, Recurring [Member] | U.S. Government agency small business administration pools guaranteed by the SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	11,901		13,125
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	35,906		19,362
Fair Value, Measurements, Recurring [Member] | Residential mortgage backed securities [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	58,907		48,462
Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	27,740		29,532
Fair Value, Measurements, Recurring [Member] | Corporate debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	487		484
Fair Value, Measurements, Recurring [Member] | Corporate subordinated debt [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	7,903		7,865
Fair Value, Measurements, Recurring [Member] | Derivative [Member]
Other assets:
Other assets, at fair value	64		114
Other liabilities:
Other liabilities, at fair value	179		114
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	1,438		1,387
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government agency small business administration pools guaranteed by the SBA [Member]
Securities available-for-sale:
Securities available-for-sale, at fair value	11,901		13,125
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	35,906		19,362
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	58,907		48,462
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	27,740		29,532
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	487		484
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	7,903		7,865
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivative [Member]
Other assets:
Other assets, at fair value	64		114
Other liabilities:
Other liabilities, at fair value	179		114
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member]
Other assets:
Other assets, at fair value	280		305
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member] | Fair Value, Inputs, Level 3 [Member]
Other assets:
Other assets, at fair value	$ 280		$ 305
[1] Actual maturities for these debt securities are dependent upon the interest rate environment and prepayments on the underlying loans.

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