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Investment Securities, AFS and HTM Securities Gross Unrealized Losses (Details) $ in Thousands | Sep. 30, 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 | 18 | 141
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (329) | $ (14,323)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 64,122 | $ 1,694,159
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 50 | 54
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (12,017) | $ (15,890)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 249,745 | 259,134
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (12,346) | (30,213)
Debt Securities, Available-for-sale, Unrealized Loss Position | 313,868 | 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 | (3,627) | (13,665)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 259,999 | 529,064
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (487,450) | (582,241)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 2,597,622 | 2,519,595
Total unrealized losses on held to maturity securities | (491,077) | (595,906)
Total fair value of unrealized losses on held to maturity securities | $ 2,857,621 | 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 | 0 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ 0 | $ (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 0 | $ 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 | $ (45) | $ (55)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 838 | 828
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (45) | (58)
Debt Securities, Available-for-sale, Unrealized Loss Position | 838 | 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 | (3,421) | (11,860)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 241,505 | 483,073
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (150,141) | (162,343)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 934,607 | 866,949
Total unrealized losses on held to maturity securities | (153,562) | (174,202)
Total fair value of unrealized losses on held to maturity securities | 1,176,112 | 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 | (53,549) | (65,963)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 261,038 | 266,353
Total unrealized losses on held to maturity securities | (53,549) | (65,963)
Total fair value of unrealized losses on held to maturity securities | $ 261,038 | $ 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 | 1 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (23) | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 6,372 | $ 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 | $ (708) | $ (604)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 57,378 | 62,830
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (731) | (604)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 63,750 | $ 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 | 2 | 4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (15) | $ (24)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 261 | 464
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (15) | (24)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 261 | $ 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 | 0 | 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 | $ 0 | $ 993
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 | 1
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 | $ (3)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 997
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | 0 | (11)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 0 | $ 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 | 5 | 23
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (44) | $ (607)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 5,235 | $ 31,983
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 15 | 14
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (5,845) | $ (8,927)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 61,665 | 61,596
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (5,888) | (9,534)
Debt Securities, Available-for-sale, Unrealized Loss Position | 66,900 | 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 | (1) | (280)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 181 | 11,617
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (150,817) | (186,184)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 697,875 | 710,114
Total unrealized losses on held to maturity securities | (150,818) | (186,464)
Total fair value of unrealized losses on held to maturity securities | $ 698,056 | $ 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 | $ (1,055) | $ (1,332)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 16,999 | 17,000
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,055) | (1,332)
Debt Securities, Available-for-sale, Unrealized Loss Position | 16,999 | 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 | (205) | (1,343)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 18,314 | 25,518
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (125,429) | (157,735)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 631,038 | 598,077
Total unrealized losses on held to maturity securities | (125,634) | (159,078)
Total fair value of unrealized losses on held to maturity securities | $ 649,352 | $ 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 | 12 | 116
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (263) | $ (13,706)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 52,515 | $ 1,660,642
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 3 | 4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (33) | $ (145)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 2,675 | 3,945
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (295) | (13,851)
Debt Securities, Available-for-sale, Unrealized Loss Position | 55,189 | 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 | 0 | (183)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value | 0 | 8,856
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (2,490) | (3,591)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 31,066 | 31,071
Total unrealized losses on held to maturity securities | (2,490) | (3,774)
Total fair value of unrealized losses on held to maturity securities | $ 31,066 | $ 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 | 15 | 16
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (4,317) | $ (4,800)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 109,930 | 111,475
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (4,317) | (4,800)
Debt Securities, Available-for-sale, Unrealized Loss Position | 109,930 | 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 | (5,023) | (6,424)
Debt Securities, Held-to-Maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value | 41,998 | 46,032
Total unrealized losses on held to maturity securities | (5,023) | (6,424)
Total fair value of unrealized losses on held to maturity securities | $ 41,998 | $ 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 | 154 | 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 | 151 | 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 | 2 | 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 | 0 | 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 | 878 | 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 | 614 | 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 | 109 | 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 | 44 | 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 | 80 | 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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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479106/326-30-50-4 + Details
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