Investment Securities and Other Investments - Summary of Unrealized Losses (Detail) $ in Thousands	Mar. 31, 2024 USD ($) Security	Dec. 31, 2023 USD ($) Security
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	224	219
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 13,212	$ 15,785
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(711)	(885)
Available-for-sale Securities, Fair Value, 12 Months or Greater	297,791	300,674
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(60,792)	(57,700)
Fair Value, Total	311,003	316,459
Unrealized Losses, Total	$ (61,503)	$ (58,585)
State and Municipal [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	70	65
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 977	$ 536
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(7)	(9)
Available-for-sale Securities, Fair Value, 12 Months or Greater	41,308	41,118
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(7,580)	(7,348)
Fair Value, Total	42,285	41,654
Unrealized Losses, Total	$ (7,587)	$ (7,357)
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	$ 279	$ 283
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(1)	(1)
Available-for-sale Securities, Fair Value, 12 Months or Greater	67,854	68,399
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(11,498)	(10,984)
Fair Value, Total	68,133	68,682
Unrealized Losses, Total	$ (11,499)	$ (10,985)
Mortgage Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	85	86
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 5,103	$ 7,497
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(6)	(45)
Available-for-sale Securities, Fair Value, 12 Months or Greater	164,119	169,474
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(37,628)	(35,199)
Fair Value, Total	169,222	176,971
Unrealized Losses, Total	$ (37,634)	$ (35,244)
Corporate Bonds [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Number of Securities \| Security	40	39
Available-for-sale Securities, Fair Value, Less Than 12 Months	$ 6,853	$ 7,469
Available-for-sale Securities, Unrealized Losses, Less Than 12 Months	(697)	(830)
Available-for-sale Securities, Fair Value, 12 Months or Greater	24,510	21,683
Available-for-sale Securities, Unrealized Losses, 12 months or Greater	(4,086)	(4,169)
Fair Value, Total	31,363	29,152
Unrealized Losses, Total	$ (4,783)	$ (4,999)

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