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)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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