Investment Securities - Summary of Fair Value of Available For Sale Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	$ 47,657	$ 24,488
Less than 12 Months Unrealized Losses	(385)	(55)
More than 12 Months Fair Value	59,047	66,250
More than 12 Months Unrealized Losses	(8,632)	(8,010)
Fair Value	106,704	90,738
Unrealized Losses	(9,017)	(8,065)
Mortgage-backed securities - U.S. Government Sponsored Enterprises (GSEs) [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	31,198	22,206
Less than 12 Months Unrealized Losses	(174)	(52)
More than 12 Months Fair Value	28,698	29,492
More than 12 Months Unrealized Losses	(5,122)	(5,029)
Fair Value	59,896	51,698
Unrealized Losses	(5,296)	(5,081)
U.S. government agency securities [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	4,964	0
Less than 12 Months Unrealized Losses	(36)	0
More than 12 Months Fair Value	5,471	5,510
More than 12 Months Unrealized Losses	(789)	(750)
Fair Value	10,435	5,510
Unrealized Losses	(825)	(750)
Obligations of state and political subdivisions [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	11,304	1,901
Less than 12 Months Unrealized Losses	(174)	(3)
More than 12 Months Fair Value	24,660	31,025
More than 12 Months Unrealized Losses	(2,721)	(2,230)
Fair Value	35,964	32,926
Unrealized Losses	(2,895)	(2,233)
Small business association (SBA) securities [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	191	381
Less than 12 Months Unrealized Losses	(1)	0
More than 12 Months Fair Value	218	223
More than 12 Months Unrealized Losses	0	(1)
Fair Value	409	604
Unrealized Losses	(1)	$ (1)
U.S. Treasuries [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	0
Less than 12 Months Unrealized Losses	0
More than 12 Months Fair Value	0
More than 12 Months Unrealized Losses	0
Fair Value	0
Unrealized Losses	$ 0

Debt securities available for sale unrealized loss position fair value.

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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