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Securities Available-for-Sale - Summary of gross unrealized losses and fair value for those investments with unrealized losses (Detail) $ in Thousands | Sep. 30, 2025 USD ($) Number | Dec. 31, 2024 USD ($) Number
--- | --- | ---
Less than 12 Months, Number of Securities | Number | 16 | 35
Less than 12 Months, Fair Value | $ 16,867 | $ 39,378
Less than 12 Months, Unrealized Losses | $ (207) | $ (588)
More than 12 Months, Number of Securities | Number | 81 | 81
More than 12 Months, Fair Value | $ 55,386 | $ 57,092
More than 12 Months, Unrealized Losses | (8,589) | (9,688)
Total, Fair Value | 72,253 | 96,470
Total, Unrealized Losses | $ (8,796) | $ (10,276)
U.S. Government sponsored enterprises obligations [Member] |  |
More than 12 Months, Number of Securities | Number | 3 | 3
More than 12 Months, Fair Value | $ 1,448 | $ 1,387
More than 12 Months, Unrealized Losses | (174) | (255)
Total, Fair Value | 1,448 | 1,387
Total, Unrealized Losses | $ (174) | $ (255)
U.S. Government agency small business administration pools guaranteed by SBA [Member] |  |
Less than 12 Months, Number of Securities | Number | 7 | 5
Less than 12 Months, Fair Value | $ 4,930 | $ 4,245
Less than 12 Months, Unrealized Losses | $ (49) | $ (28)
More than 12 Months, Number of Securities | Number | 8 | 8
More than 12 Months, Fair Value | $ 5,704 | $ 6,224
More than 12 Months, Unrealized Losses | (716) | (874)
Total, Fair Value | 10,634 | 10,469
Total, Unrealized Losses | $ (765) | $ (902)
Collateralized mortgage obligations issued by the FHLMC, FNMA and GNMA [Member] |  |
Less than 12 Months, Number of Securities | Number | 5 | 7
Less than 12 Months, Fair Value | $ 9,275 | $ 11,913
Less than 12 Months, Unrealized Losses | $ (82) | $ (126)
More than 12 Months, Number of Securities | Number | 4 | 4
More than 12 Months, Fair Value | $ 2,225 | $ 2,256
More than 12 Months, Unrealized Losses | (349) | (470)
Total, Fair Value | 11,500 | 14,169
Total, Unrealized Losses | $ (431) | $ (596)
Residential mortgage backed securities [Member] |  |
Less than 12 Months, Number of Securities | Number | 3 | 20
Less than 12 Months, Fair Value | $ 2,408 | $ 22,395
Less than 12 Months, Unrealized Losses | $ (69) | $ (422)
More than 12 Months, Number of Securities | Number | 25 | 24
More than 12 Months, Fair Value | $ 14,644 | $ 14,485
More than 12 Months, Unrealized Losses | (3,162) | (3,960)
Total, Fair Value | 17,052 | 36,880
Total, Unrealized Losses | $ (3,231) | $ (4,382)
Municipal bonds [Member] |  |
Less than 12 Months, Number of Securities | Number | 1 | 3
Less than 12 Months, Fair Value | $ 254 | $ 825
Less than 12 Months, Unrealized Losses | $ (7) | $ (12)
More than 12 Months, Number of Securities | Number | 36 | 36
More than 12 Months, Fair Value | $ 26,732 | $ 27,369
More than 12 Months, Unrealized Losses | (3,822) | (3,490)
Total, Fair Value | 26,986 | 28,194
Total, Unrealized Losses | $ (3,829) | $ (3,502)
Corporate debt [Member] |  |
More than 12 Months, Number of Securities | Number | 1 | 1
More than 12 Months, Fair Value | $ 488 | $ 484
More than 12 Months, Unrealized Losses | (12) | (16)
Total, Fair Value | 488 | 484
Total, Unrealized Losses | $ (12) | $ (16)
Corporate subordinated debt [Member] |  |
More than 12 Months, Number of Securities | Number | 4 | 5
More than 12 Months, Fair Value | $ 4,145 | $ 4,887
More than 12 Months, Unrealized Losses | (354) | (623)
Total, Fair Value | 4,145 | 4,887
Total, Unrealized Losses | $ (354) | $ (623)

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