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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 | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | $ 142,520 |  | $ 120,217
U.S. Government-sponsored enterprises ("GSE") obligations [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 1,448 |  | 1,387
U.S. Government agency small business administration pools guaranteed by SBA [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 11,222 | [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 | 34,951 | [1] | 19,362
Residential mortgage-backed GSE securities [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 57,985 | [1] | 48,462
Municipal bonds [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 28,854 |  | 29,532
Corporate debt [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 488 |  | 484
Corporate subordinated debt [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 7,572 |  | 7,865
Fair Value, Measurements, Recurring [Member] | U.S. Government-sponsored enterprises ("GSE") obligations [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 1,448 |  | 1,387
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 | 11,222 |  | 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 | 34,951 |  | 19,362
Fair Value, Measurements, Recurring [Member] | Residential mortgage-backed GSE securities [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 57,985 |  | 48,462
Fair Value, Measurements, Recurring [Member] | Municipal bonds [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 28,854 |  | 29,532
Fair Value, Measurements, Recurring [Member] | Corporate debt [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 488 |  | 484
Fair Value, Measurements, Recurring [Member] | Corporate subordinated debt [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 7,572 |  | 7,865
Fair Value, Measurements, Recurring [Member] | Derivatives [Member] |  |  |
Other assets: |  |  |
Other assets, at fair value | 76 |  | 114
Other liabilities: |  |  |
Other liabilities, at fair value | 207 |  | 114
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Government-sponsored enterprises ("GSE") obligations [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 1,448 |  | 1,387
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 | 11,222 |  | 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 | 34,951 |  | 19,362
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Residential mortgage-backed GSE securities [Member] |  |  |
Securities available-for-sale: |  |  |
Securities available-for-sale, at fair value | 57,985 |  | 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 | 28,854 |  | 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 | 488 |  | 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 | 7,572 |  | 7,865
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Derivatives [Member] |  |  |
Other assets: |  |  |
Other assets, at fair value | 76 |  | 114
Other liabilities: |  |  |
Other liabilities, at fair value | 207 |  | 114
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member] |  |  |
Other assets: |  |  |
Other assets, at fair value | 267 |  | 305
Fair Value, Measurements, Recurring [Member] | Mortgage servicing rights [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Other assets: |  |  |
Other assets, at fair value | $ 267 |  | $ 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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