Investment Securities - Schedule of AFS Debt Securities in an Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 309,470	$ 238,023
Less Than 12 Months, Gross Unrealized Losses	(676)	(4,044)
12 Months or Longer, Fair Value	2,050,731	2,089,545
12 Months or Longer, Gross Unrealized Losses	(258,459)	(281,739)
Total Fair Value	2,360,201	2,327,568
Total Gross Unrealized Losses	(259,135)	(285,783)
Debt Securities Issued by the U.S. Treasury and Government Agencies
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	38,854	7,171
Less Than 12 Months, Gross Unrealized Losses	(288)	(16)
12 Months or Longer, Fair Value	157,456	155,341
12 Months or Longer, Gross Unrealized Losses	(7,897)	(11,080)
Total Fair Value	196,310	162,512
Total Gross Unrealized Losses	(8,185)	(11,096)
Debt Securities Issued by States and Political Subdivisions
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value		237
Less Than 12 Months, Gross Unrealized Losses		(2)
12 Months or Longer, Fair Value	63,644	63,509
12 Months or Longer, Gross Unrealized Losses	(9,349)	(9,609)
Total Fair Value	63,644	63,746
Total Gross Unrealized Losses	(9,349)	(9,611)
Debt Securities Issued by Government-Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
12 Months or Longer, Fair Value	1,464	1,476
12 Months or Longer, Gross Unrealized Losses	(41)	(80)
Total Fair Value	1,464	1,476
Total Gross Unrealized Losses	(41)	(80)
Debt Securities Issued by Corporations
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	24,892	220,987
Less Than 12 Months, Gross Unrealized Losses	(108)	(4,013)
12 Months or Longer, Fair Value	546,407	411,573
12 Months or Longer, Gross Unrealized Losses	(32,172)	(44,430)
Total Fair Value	571,299	632,560
Total Gross Unrealized Losses	(32,280)	(48,443)
Residential - Government Agencies or Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	153,104	9,624
Less Than 12 Months, Gross Unrealized Losses	(275)	(13)
12 Months or Longer, Fair Value	673,141	763,476
12 Months or Longer, Gross Unrealized Losses	(115,126)	(118,138)
Total Fair Value	826,245	773,100
Total Gross Unrealized Losses	(115,401)	(118,151)
Commercial - Government Agencies or Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	92,485
Less Than 12 Months, Gross Unrealized Losses	(5)
12 Months or Longer, Fair Value	128,430	134,923
12 Months or Longer, Gross Unrealized Losses	(23,416)	(22,592)
Total Fair Value	220,915	134,923
Total Gross Unrealized Losses	(23,421)	(22,592)
Collateralized Mortgage Obligations
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	245,589	9,624
Less Than 12 Months, Gross Unrealized Losses	(280)	(13)
12 Months or Longer, Fair Value	801,571	898,399
12 Months or Longer, Gross Unrealized Losses	(138,542)	(140,730)
Total Fair Value	1,047,160	908,023
Total Gross Unrealized Losses	(138,822)	(140,743)
Residential - Government Agencies or Sponsored Enterprises
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	135	4
12 Months or Longer, Fair Value	480,189	559,247
12 Months or Longer, Gross Unrealized Losses	(70,458)	(75,810)
Total Fair Value	480,324	559,251
Total Gross Unrealized Losses	(70,458)	(75,810)
Mortgage-Backed Securities
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	135	4
12 Months or Longer, Fair Value	480,189	559,247
12 Months or Longer, Gross Unrealized Losses	(70,458)	(75,810)
Total Fair Value	480,324	559,251
Total Gross Unrealized Losses	$ (70,458)	$ (75,810)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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