Securities - Summary of Amortized Cost and Fair Values of Securities Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	$ 1,573,276	$ 1,516,801
Available-for-sale Securities, Gross Unrealized Gains	1,573	4,743
Available-for-sale Securities, Gross Unrealized Losses	(188,022)	(179,064)
Available-for-sale Securities, Fair Value	1,386,827	1,342,480
U.S. Treasury Notes
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	52,638	116,398
Available-for-sale Securities, Gross Unrealized Gains	0	61
Available-for-sale Securities, Gross Unrealized Losses	(853)	(1,025)
Available-for-sale Securities, Fair Value	51,785	115,434
U.S. Government Agencies
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	164,453	147,062
Available-for-sale Securities, Gross Unrealized Gains	20	37
Available-for-sale Securities, Gross Unrealized Losses	(17,299)	(16,404)
Available-for-sale Securities, Fair Value	147,174	130,695
Obligations of States, Municipalities, and Political Subdivisions
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	85,541	86,022
Available-for-sale Securities, Gross Unrealized Gains	154	396
Available-for-sale Securities, Gross Unrealized Losses	(5,305)	(4,143)
Available-for-sale Securities, Fair Value	80,390	82,275
Agency, Residential Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	850,340	786,970
Available-for-sale Securities, Gross Unrealized Gains	1,377	4,247
Available-for-sale Securities, Gross Unrealized Losses	(102,519)	(95,414)
Available-for-sale Securities, Fair Value	749,198	695,803
Non-Agency, Residential Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	131,968	122,359
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	(22,914)	(22,099)
Available-for-sale Securities, Fair Value	109,054	100,260
Agency, Commercial Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	227,984	181,452
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	(34,036)	(34,248)
Available-for-sale Securities, Fair Value	193,948	147,204
Corporate Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	40,652	40,681
Available-for-sale Securities, Gross Unrealized Gains	0	0
Available-for-sale Securities, Gross Unrealized Losses	(3,872)	(4,510)
Available-for-sale Securities, Fair Value	36,780	36,171
Asset-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	19,700	35,857
Available-for-sale Securities, Gross Unrealized Gains	22	2
Available-for-sale Securities, Gross Unrealized Losses	(1,224)	(1,221)
Available-for-sale Securities, Fair Value	$ 18,498	$ 34,638

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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