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Investment Securities, AFS and HTM Securities Gross Unrealized Losses (Details) $ in Thousands | Sep. 30, 2024 USD ($) security | Dec. 31, 2023 USD ($) 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 | 24 | 82
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (93) | $ (4,773)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 35,160 | $ 307,527
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 254 | 213
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (130,289) | $ (168,728)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,407,452 | 1,392,635
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (130,382) | (173,501)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,442,613 | 1,700,162
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | (518) | (2,184)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 111,598 | 220,865
Unrealized losses on held to maturity securities, 12 months or more | (464,613) | (533,046)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 2,653,401 | 2,566,468
Total unrealized losses on held to maturity securities | (465,131) | (535,230)
Total fair value of unrealized losses on held to maturity securities | $ 2,765,000 | $ 2,787,333
US Treasury 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 | 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 | $ (3,039) | $ (4,083)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 36,948 | 35,902
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (3,039) | (4,083)
Debt Securities, Available-for-sale, Unrealized Loss Position | 36,948 | 35,902
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Fair value of unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Unrealized losses on held to maturity securities, 12 months or more | (10) | (36)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 990 | 963
Total unrealized losses on held to maturity securities | (10) | (36)
Total fair value of unrealized losses on held to maturity securities | $ 990 | $ 963
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 | 18 | 41
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (35) | $ (347)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 8,205 | $ 23,762
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 112 | 92
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (1,731) | $ (1,867)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 66,172 | 53,022
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,766) | (2,214)
Debt Securities, Available-for-sale, Unrealized Loss Position | 74,377 | 76,784
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | (517) | (1,535)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 111,498 | 180,270
Unrealized losses on held to maturity securities, 12 months or more | (128,470) | (132,518)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 887,316 | 792,940
Total unrealized losses on held to maturity securities | (128,987) | (134,053)
Total fair value of unrealized losses on held to maturity securities | 998,814 | 973,210
Mortgage-backed Securities, Issued by Private Enterprises [Member] |  |
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Fair value of unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Unrealized losses on held to maturity securities, 12 months or more | (55,765) | (65,372)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 282,103 | 289,507
Total unrealized losses on held to maturity securities | (55,765) | (65,372)
Total fair value of unrealized losses on held to maturity securities | $ 282,103 | $ 289,507
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 | 14
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (922) | $ (1,862)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 65,319 | 125,339
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (922) | (1,862)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 65,319 | $ 125,339
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 | 5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (24) | $ (28)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 498 | 761
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (24) | (28)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 498 | $ 761
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 | 0 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ (9)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 991
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 1 | 2
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (3) | $ (42)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 997 | 1,958
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (3) | (50)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 997 | $ 2,950
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 | 4 | 18
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (22) | $ (333)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 6,211 | $ 22,870
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 82 | 71
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (117,522) | $ (153,219)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,026,799 | 1,080,337
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (117,544) | (153,552)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,033,011 | 1,103,207
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | (1) | (511)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 100 | 30,323
Unrealized losses on held to maturity securities, 12 months or more | (145,884) | (164,076)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 769,122 | 771,042
Total unrealized losses on held to maturity securities | (145,885) | (164,587)
Total fair value of unrealized losses on held to maturity securities | $ 769,223 | $ 801,365
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 | $ (388) | $ (1,755)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 18,035 | 16,937
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (388) | (1,755)
Debt Securities, Available-for-sale, Unrealized Loss Position | 18,035 | 16,937
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | 0 | (121)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 0 | 8,144
Unrealized losses on held to maturity securities, 12 months or more | (126,498) | (160,660)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 632,665 | 624,770
Total unrealized losses on held to maturity securities | (126,498) | (160,781)
Total fair value of unrealized losses on held to maturity securities | $ 632,665 | $ 632,914
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 | 2 | 13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (36) | $ (924)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 20,744 | $ 156,847
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 10 | 5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (1,405) | $ (1,898)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 41,066 | 26,643
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,441) | (2,822)
Debt Securities, Available-for-sale, Unrealized Loss Position | 61,811 | 183,490
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | 0 | (17)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 0 | 2,128
Unrealized losses on held to maturity securities, 12 months or more | (2,344) | (2,884)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 33,584 | 34,626
Total unrealized losses on held to maturity securities | (2,344) | (2,901)
Total fair value of unrealized losses on held to maturity securities | $ 33,584 | $ 36,754
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 | 9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ (3,160)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 103,055
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 31 | 22
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (5,256) | $ (3,975)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 151,617 | 51,738
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (5,256) | (7,135)
Debt Securities, Available-for-sale, Unrealized Loss Position | 151,617 | 154,793
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position [Abstract] |  |
Unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Fair value of unrealized losses on held to maturity securities, less than 12 months | 0 | 0
Unrealized losses on held to maturity securities, 12 months or more | (5,643) | (7,500)
Fair value of unrealized losses on held to maturity securities, 12 months or more | 47,620 | 52,619
Total unrealized losses on held to maturity securities | (5,643) | (7,500)
Total fair value of unrealized losses on held to maturity securities | $ 47,620 | $ 52,619
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 | 84 | 205
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 | 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 | 83 | 182
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 | 1 | 20
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 | 0 | 1
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 | 0 | 2
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 | 904 | 785
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 | 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 | 642 | 537
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 | 108 | 94
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 | 44
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 | 78
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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