Investment Securities and Other Investments - Summary of Unrealized Losses (Detail) $ in Thousands	Mar. 31, 2026 USD ($) Security	Dec. 31, 2025 USD ($) Security
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	206	197
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 28,758	$ 8,311
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(340)	(177)
Available-for-sale Securities, Fair Value, 12 Months or Greater	274,494	282,193
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(40,245)	(40,491)
Fair Value, Total	303,252	290,504
Unrealized Losses, Total	$ (40,585)	$ (40,668)
State and Municipal [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	56	57
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 1,933	$ 679
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(9)	(2)
Available-for-sale Securities, Fair Value, 12 Months or Greater	39,143	39,908
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(4,967)	(4,728)
Fair Value, Total	41,076	40,587
Unrealized Losses, Total	$ (4,976)	$ (4,730)
U.S. Treasury and Agencies [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	29	29
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 0	$ 0
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	0	0
Available-for-sale Securities, Fair Value, 12 Months or Greater	72,070	72,538
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(6,345)	(6,290)
Fair Value, Total	72,070	72,538
Unrealized Losses, Total	$ (6,345)	$ (6,290)
Mortgage Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	91	80
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 21,563	$ 5,889
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(188)	(16)
Available-for-sale Securities, Fair Value, 12 Months or Greater	142,382	145,498
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(27,333)	(27,647)
Fair Value, Total	163,945	151,387
Unrealized Losses, Total	$ (27,521)	$ (27,663)
Corporate Bonds [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	30	31
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 5,262	$ 1,743
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(143)	(159)
Available-for-sale Securities, Fair Value, 12 Months or Greater	20,899	24,249
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(1,600)	(1,826)
Fair Value, Total	26,161	25,992
Unrealized Losses, Total	$ (1,743)	$ (1,985)

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