Investment Securities and Other Investments - Summary of Unrealized Losses (Detail) $ in Thousands	Mar. 31, 2025 USD ($) Security	Dec. 31, 2024 USD ($) Security
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	222	226
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 14,450	$ 17,480
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(65)	(170)
Available-for-sale Securities, Fair Value, 12 Months or Greater	295,048	293,439
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(50,317)	(55,364)
Fair Value, Total	309,498	310,919
Unrealized Losses, Total	$ (50,382)	$ (55,534)
State and Municipal [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	69	70
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 1,686	$ 2,040
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(10)	(42)
Available-for-sale Securities, Fair Value, 12 Months or Greater	41,430	40,531
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(6,362)	(7,254)
Fair Value, Total	43,116	42,571
Unrealized Losses, Total	$ (6,372)	$ (7,296)
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	70,615	69,453
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(8,465)	(9,975)
Fair Value, Total	70,615	69,453
Unrealized Losses, Total	$ (8,465)	$ (9,975)
Mortgage Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	84	85
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 11,008	$ 11,637
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(53)	(107)
Available-for-sale Securities, Fair Value, 12 Months or Greater	151,569	152,802
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(32,797)	(34,908)
Fair Value, Total	162,577	164,439
Unrealized Losses, Total	$ (32,850)	$ (35,015)
Corporate Bonds [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	40	42
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 1,756	$ 3,803
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(2)	(21)
Available-for-sale Securities, Fair Value, 12 Months or Greater	31,434	30,653
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(2,693)	(3,227)
Fair Value, Total	33,190	34,456
Unrealized Losses, Total	$ (2,695)	$ (3,248)

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