Investment Securities - Summary of Fair Value of Available For Sale Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	$ 38,327	$ 129,849
Less than 12 Months Unrealized Losses	(131)	(1,214)
More than 12 Months Fair Value	64,711	69,181
More than 12 Months Unrealized Losses	(8,527)	(11,719)
Fair Value	103,038	199,030
Unrealized Losses	(8,658)	(12,933)
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	31,883	122,763
Less than 12 Months Unrealized Losses	(121)	(1,157)
More than 12 Months Fair Value	27,639	29,229
More than 12 Months Unrealized Losses	(5,202)	(6,512)
Fair Value	59,522	151,992
Unrealized Losses	(5,323)	(7,669)
U.S. government agency securities [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	4,992	129
Less than 12 Months Unrealized Losses	(8)	0
More than 12 Months Fair Value	5,635	5,183
More than 12 Months Unrealized Losses	(783)	(1,077)
Fair Value	10,627	5,312
Unrealized Losses	(791)	(1,077)
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	759	3,664
Less than 12 Months Unrealized Losses	0	(39)
More than 12 Months Fair Value	31,358	34,320
More than 12 Months Unrealized Losses	(2,541)	(4,127)
Fair Value	32,117	37,984
Unrealized Losses	(2,541)	(4,166)
Small business association (SBA) securities [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	693	447
Less than 12 Months Unrealized Losses	(2)	(1)
More than 12 Months Fair Value	79	449
More than 12 Months Unrealized Losses	(1)	(3)
Fair Value	772	896
Unrealized Losses	(3)	(4)
U.S. Treasuries [Member]
Debt Securities Available For Sale Unrealized Loss Position Fair Value [Line Items]
Less than 12 Months Fair Value	0	2,846
Less than 12 Months Unrealized Losses	0	(17)
More than 12 Months Fair Value	0	0
More than 12 Months Unrealized Losses	0	0
Fair Value	0	2,846
Unrealized Losses	$ 0	$ (17)

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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