Investment Securities - Summary of Amortized Cost and Estimated Fair Value (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	$ 173,093	$ 189,924
Gross Unrealized Gains	481	710
Gross Unrealized Losses	(9,017)	(8,065)
Securities available-for-sale, at fair value	164,557	182,569
Mortgage-backed securities - U.S. Government Sponsored Enterprises (GSEs) [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	116,939	132,040
Gross Unrealized Gains	472	688
Gross Unrealized Losses	(5,296)	(5,081)
Securities available-for-sale, at fair value	112,115	127,647
U.S. government agency securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	11,260	11,260
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(825)	(750)
Securities available-for-sale, at fair value	10,435	10,512
Obligations of state and political subdivisions [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	41,867	42,423
Gross Unrealized Gains	2	8
Gross Unrealized Losses	(2,895)	(2,233)
Securities available-for-sale, at fair value	38,974	40,198
Small business association (SBA) securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	1,064	1,254
Gross Unrealized Gains	6	6
Gross Unrealized Losses	(1)	(1)
Securities available-for-sale, at fair value	1,069	1,259
US Treasury Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Amortized cost	1,963	2,947
Gross Unrealized Gains	1	6
Gross Unrealized Losses	0	0
Securities available-for-sale, at fair value	$ 1,964	$ 2,953

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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