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Investment Securities, AFS and HTM Securities Gross Unrealized Losses (Details) $ in Thousands | Mar. 31, 2025 USD ($) security | Dec. 31, 2024 USD ($) security
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Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 51 | 141
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (2,070) | $ (14,323)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 648,254 | $ 1,694,159
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 55 | 54
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (13,815) | $ (15,890)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 258,155 | 259,134
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (15,885) | (30,213)
Debt Securities, Available-for-sale, Unrealized Loss Position | 906,409 | 1,953,294
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (16,161) | (13,665)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 522,436 | 529,064
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (555,958) | (582,241)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 2,547,298 | 2,519,595
Total unrealized losses on held to maturity securities | (572,119) | (595,906)
Total fair value of unrealized losses on held to maturity securities | $ 3,069,734 | 3,048,660
US Treasury Securities |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value |  | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | (1)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value |  | 999
Total unrealized losses on held to maturity securities |  | (1)
Total fair value of unrealized losses on held to maturity securities |  | $ 999
US States and Political Subdivisions Debt Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 1 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (5) | $ (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 540 | $ 542
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 2 | 2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (63) | $ (55)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 820 | 828
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (68) | (58)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,360 | 1,370
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (15,784) | (11,860)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 497,155 | 483,073
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (179,117) | (162,343)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 876,233 | 866,949
Total unrealized losses on held to maturity securities | (194,901) | (174,202)
Total fair value of unrealized losses on held to maturity securities | 1,373,388 | 1,350,022
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 0 | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (59,642) | (65,963)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 268,201 | 266,353
Total unrealized losses on held to maturity securities | (59,642) | (65,963)
Total fair value of unrealized losses on held to maturity securities | $ 268,201 | $ 266,353
Federal Family Education Loan Program (FFELP) Guaranteed Loans [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 12 | 12
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (911) | $ (604)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 60,939 | 62,830
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (911) | (604)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 60,939 | $ 62,830
US Government-sponsored Enterprises Debt Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 4 | 4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (17) | $ (24)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 399 | 464
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (17) | (24)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 399 | $ 464
Other Debt securities |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 1 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ (7)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 1,000 | $ 993
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 1 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (1) | $ (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 999 | 997
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1) | (11)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 1,999 | $ 1,989
US Government Sponsored-Enterprise Insured Loans | Residential Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 17 | 23
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (243) | $ (607)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 23,292 | $ 31,983
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 14 | 14
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (7,231) | $ (8,927)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 61,639 | 61,596
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (7,474) | (9,534)
Debt Securities, Available-for-sale, Unrealized Loss Position | 84,931 | 93,579
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (122) | (280)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 9,717 | 11,617
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (169,359) | (186,184)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 712,109 | 710,114
Total unrealized losses on held to maturity securities | (169,482) | (186,464)
Total fair value of unrealized losses on held to maturity securities | $ 721,825 | $ 721,732
US Government Sponsored-Enterprise Insured Loans | Commercial Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 1 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (1,281) | $ (1,332)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 16,959 | 17,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,281) | (1,332)
Debt Securities, Available-for-sale, Unrealized Loss Position | 16,959 | 17,000
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (178) | (1,343)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 8,091 | 25,518
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (139,030) | (157,735)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 613,936 | 598,077
Total unrealized losses on held to maturity securities | (139,208) | (159,078)
Total fair value of unrealized losses on held to maturity securities | $ 622,027 | $ 623,595
Government National Mortgage Association (GNMA) [Member] | Residential Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 32 | 116
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (1,822) | $ (13,706)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 623,422 | $ 1,660,642
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 5 | 4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (91) | $ (145)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 4,967 | 3,945
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,913) | (13,851)
Debt Securities, Available-for-sale, Unrealized Loss Position | 628,389 | 1,664,587
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (77) | (183)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 7,474 | 8,856
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (2,932) | (3,591)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 31,198 | 31,071
Total unrealized losses on held to maturity securities | (3,009) | (3,774)
Total fair value of unrealized losses on held to maturity securities | $ 38,671 | $ 39,927
Government National Mortgage Association (GNMA) [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Schedule of Available-for-sale and Held-to-maturity Securities [Line Items] |  |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 16 | 16
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (4,221) | $ (4,800)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 111,433 | 111,475
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (4,221) | (4,800)
Debt Securities, Available-for-sale, Unrealized Loss Position | 111,433 | 111,475
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 0 | 0
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (5,877) | (6,424)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 45,621 | 46,032
Total unrealized losses on held to maturity securities | (5,877) | (6,424)
Total fair value of unrealized losses on held to maturity securities | $ 45,621 | $ 46,032
Held to maturity, number of securities, less than 12 months |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 385 | 391
Held to maturity, number of securities, less than 12 months | US Treasury Securities |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security |  | 0
Held to maturity, number of securities, less than 12 months | US States and Political Subdivisions Debt Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 369 | 370
Held to maturity, number of securities, less than 12 months | Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 0 | 0
Held to maturity, number of securities, less than 12 months | US Government Sponsored-Enterprise Insured Loans | Residential Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 9 | 12
Held to maturity, number of securities, less than 12 months | US Government Sponsored-Enterprise Insured Loans | Commercial Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 1 | 2
Held to maturity, number of securities, less than 12 months | Government National Mortgage Association (GNMA) [Member] | Residential Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 6 | 7
Held to maturity, number of securities, less than 12 months | Government National Mortgage Association (GNMA) [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 0 | 0
Held to maturity, number of securities, 12 months or more |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 924 | 901
Held to maturity, number of securities, 12 months or more | US Treasury Securities |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security |  | 1
Held to maturity, number of securities, 12 months or more | US States and Political Subdivisions Debt Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 665 | 641
Held to maturity, number of securities, 12 months or more | Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 18 | 18
Held to maturity, number of securities, 12 months or more | US Government Sponsored-Enterprise Insured Loans | Residential Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 106 | 106
Held to maturity, number of securities, 12 months or more | US Government Sponsored-Enterprise Insured Loans | Commercial Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 43 | 43
Held to maturity, number of securities, 12 months or more | Government National Mortgage Association (GNMA) [Member] | Residential Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 79 | 79
Held to maturity, number of securities, 12 months or more | Government National Mortgage Association (GNMA) [Member] | Commercial Mortgage-Backed Securities [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Held-to-Maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 13 | 13

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