Investment Securities and Other Investments - Summary of Unrealized Losses (Detail) $ in Thousands	Sep. 30, 2025 USD ($) Security	Dec. 31, 2024 USD ($) Security
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	200	226
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 12,516	$ 17,480
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(109)	(170)
Available-for-sale Securities, Fair Value, 12 Months or Greater	289,398	293,439
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(41,463)	(55,364)
Fair Value, Total	301,914	310,919
Unrealized Losses, Total	$ (41,572)	$ (55,534)
State and Municipal [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	56	70
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 0	$ 2,040
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	0	(42)
Available-for-sale Securities, Fair Value, 12 Months or Greater	41,417	40,531
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(5,060)	(7,254)
Fair Value, Total	41,417	42,571
Unrealized Losses, Total	$ (5,060)	$ (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	72,039	69,453
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(6,866)	(9,975)
Fair Value, Total	72,039	69,453
Unrealized Losses, Total	$ (6,866)	$ (9,975)
Mortgage Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	82	85
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 11,218	$ 11,637
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(9)	(107)
Available-for-sale Securities, Fair Value, 12 Months or Greater	149,494	152,802
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(27,360)	(34,908)
Fair Value, Total	160,712	164,439
Unrealized Losses, Total	$ (27,369)	$ (35,015)
Corporate Bonds [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	33	42
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 1,298	$ 3,803
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(100)	(21)
Available-for-sale Securities, Fair Value, 12 Months or Greater	26,448	30,653
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(2,177)	(3,227)
Fair Value, Total	27,746	34,456
Unrealized Losses, Total	$ (2,277)	$ (3,248)

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