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Investment Securities, AFS and HTM Securities Gross Unrealized Losses (Details) $ in Thousands | Mar. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) 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 | 207 | 120
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (93,177) | $ (34,586)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 2,044,781 | $ 2,955,152
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 26 | 17
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (22,199) | $ (920)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 305,713 | 66,478
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (115,376) | (35,506)
Debt Securities, Available-for-sale, Unrealized Loss Position | 2,350,494 | 3,021,630
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (264,255) | (8,422)
Unrealized losses on held to maturity securities, 12 months or more | (10,930) | (387)
Total unrealized losses on held to maturity securities | $ (275,186) | $ (8,809)
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, 12 Months or Longer | security | 12 | 1
Fair value of unrealized losses on held to maturity securities, less than 12 months | $ 2,586,375 | $ 533,577
Fair value of unrealized losses on held to maturity securities, 12 months or more | 77,887 | 10,775
Total fair value of unrealized losses on held to maturity securities | $ 2,664,262 | $ 544,352
Held-to-maturity, Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions, less than 12 Months | security | 510 | 72
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 | 5 | 7
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (7,346) | $ (1,334)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 107,050 | $ 122,957
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 2 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (850) | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 9,082 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (8,196) | (1,334)
Debt Securities, Available-for-sale, Unrealized Loss Position | 116,132 | $ 122,957
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (34) |
Unrealized losses on held to maturity securities, 12 months or more | 0 |
Total unrealized losses on held to maturity securities | (34) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 964 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 0 |
Total fair value of unrealized losses on held to maturity securities | $ 964 |
US Treasury Securities | Held to maturity, number of securities, less than 12 months |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 1 |
US Treasury Securities | Held to maturity, number of securities, 12 months or more |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 0 |
Agency 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 | $ (800) | $ (103)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 14,200 | $ 14,897
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (800) | (103)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 14,200 | 14,897
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 | 64 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (195) |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 35,501 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (195) |
Debt Securities, Available-for-sale, Unrealized Loss Position | 35,501 |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (79,571) | (1,951)
Unrealized losses on held to maturity securities, 12 months or more | (1,325) | 0
Total unrealized losses on held to maturity securities | (80,896) | (1,951)
Fair value of unrealized losses on held to maturity securities, less than 12 months | 576,351 | 112,038
Fair value of unrealized losses on held to maturity securities, 12 months or more | 5,100 | 0
Total fair value of unrealized losses on held to maturity securities | $ 581,451 | $ 112,038
US States and Political Subdivisions Debt Securities [Member] | Held to maturity, number of securities, less than 12 months |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 346 | 49
US States and Political Subdivisions Debt Securities [Member] | Held to maturity, number of securities, 12 months or more |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 5 | 0
Residential Related Securities | GNMA [Member] |  |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | $ (643) |
Unrealized losses on held to maturity securities, 12 months or more | 0 |
Total unrealized losses on held to maturity securities | (643) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 33,468 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 0 |
Total fair value of unrealized losses on held to maturity securities | 33,468 |
Residential Related Securities | FNMA/FHLMC |  |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (72,418) |
Unrealized losses on held to maturity securities, 12 months or more | 0 |
Total unrealized losses on held to maturity securities | (72,418) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 896,284 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 0 |
Total fair value of unrealized losses on held to maturity securities | $ 896,284 |
Residential Related Securities | Held to maturity, number of securities, less than 12 months | GNMA [Member] |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 46 |
Residential Related Securities | Held to maturity, number of securities, less than 12 months | FNMA/FHLMC |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 51 |
Residential Related Securities | Held to maturity, number of securities, 12 months or more | GNMA [Member] |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 0 |
Residential Related Securities | Held to maturity, number of securities, 12 months or more | FNMA/FHLMC |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 0 |
Commercial mortgage-related securities | GNMA [Member] |  |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months |  | $ (200)
Unrealized losses on held to maturity securities, 12 months or more |  | 0
Total unrealized losses on held to maturity securities |  | (200)
Fair value of unrealized losses on held to maturity securities, less than 12 months |  | 33,468
Fair value of unrealized losses on held to maturity securities, 12 months or more |  | 0
Total fair value of unrealized losses on held to maturity securities |  | 33,468
Commercial mortgage-related securities | FNMA/FHLMC |  |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months |  | (6,272)
Unrealized losses on held to maturity securities, 12 months or more |  | (387)
Total unrealized losses on held to maturity securities |  | (6,659)
Fair value of unrealized losses on held to maturity securities, less than 12 months |  | 388,072
Fair value of unrealized losses on held to maturity securities, 12 months or more |  | 10,775
Total fair value of unrealized losses on held to maturity securities |  | $ 398,847
Commercial mortgage-related securities | Held to maturity, number of securities, less than 12 months | GNMA [Member] |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security |  | 5
Commercial mortgage-related securities | Held to maturity, number of securities, less than 12 months | FNMA/FHLMC |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security |  | 18
Commercial mortgage-related securities | Held to maturity, number of securities, 12 months or more | GNMA [Member] |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security |  | 0
Commercial mortgage-related securities | Held to maturity, number of securities, 12 months or more | FNMA/FHLMC |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security |  | 1
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 | 7 | 4
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (1,955) | $ (256)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 110,489 | $ 64,282
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 8 | 8
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (2,135) | $ (867)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 58,489 | 62,576
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (4,090) | (1,123)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 168,978 | $ 126,858
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 | 8 | 9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (53) | $ (54)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 2,763 | 3,902
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (53) | (54)
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 2,763 | $ 3,902
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 | 2 | 3
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (27) | $ (6)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 1,973 | $ 2,994
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (27) | (6)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,973 | $ 2,994
Mortgage-backed Securities, Issued by Private Enterprises [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
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | $ (2,335)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months |  | $ 248,617
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security |  | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer |  | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss |  | (2,335)
Debt Securities, Available-for-sale, Unrealized Loss Position |  | $ 248,617
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (28,955) |
Unrealized losses on held to maturity securities, 12 months or more | 0 |
Total unrealized losses on held to maturity securities | (28,955) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 368,521 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 0 |
Total fair value of unrealized losses on held to maturity securities | $ 368,521 |
Mortgage-backed Securities, Issued by Private Enterprises [Member] | Held to maturity, number of securities, less than 12 months |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 18 |
Mortgage-backed Securities, Issued by Private Enterprises [Member] | Held to maturity, number of securities, 12 months or more |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 0 |
FNMA/FHLMC | Residential Related 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 | 88 | 74
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (80,850) | $ (21,249)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 1,617,123 | $ 2,172,837
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 8 | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ (19,161) | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 235,380 | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (100,011) | (21,249)
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,852,503 | $ 2,172,837
FNMA/FHLMC | Commercial mortgage-related 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 |  | 19
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | $ (9,302)
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months |  | $ 328,568
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security |  | 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | $ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer |  | 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss |  | (9,302)
Debt Securities, Available-for-sale, Unrealized Loss Position |  | $ 328,568
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (79,178) |
Unrealized losses on held to maturity securities, 12 months or more | (9,606) |
Total unrealized losses on held to maturity securities | (88,784) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 342,543 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 72,787 |
Total fair value of unrealized losses on held to maturity securities | $ 415,331 |
FNMA/FHLMC | Commercial mortgage-related securities | Held to maturity, number of securities, less than 12 months |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 15 |
FNMA/FHLMC | Commercial mortgage-related securities | Held to maturity, number of securities, 12 months or more |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 7 |
Government National Mortgage Association (GNMA) [Member] | Residential Related 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 | 9 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (726) |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 44,614 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (726) |
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 44,614 |
Government National Mortgage Association (GNMA) [Member] | Commercial mortgage-related 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 | 31 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | $ (1,278) |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | $ 113,831 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions | security | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | $ 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 |
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss | (1,278) |
Debt Securities, Available-for-sale, Unrealized Loss Position | 113,831 |
Investment securities HTM |  |
Unrealized losses on held to maturity securities, less than 12 months | (3,456) |
Unrealized losses on held to maturity securities, 12 months or more | 0 |
Total unrealized losses on held to maturity securities | (3,456) |
Fair value of unrealized losses on held to maturity securities, less than 12 months | 368,244 |
Fair value of unrealized losses on held to maturity securities, 12 months or more | 0 |
Total fair value of unrealized losses on held to maturity securities | $ 368,244 |
Government National Mortgage Association (GNMA) [Member] | Commercial mortgage-related securities | Held to maturity, number of securities, less than 12 months |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 33 |
Government National Mortgage Association (GNMA) [Member] | Commercial mortgage-related securities | Held to maturity, number of securities, 12 months or more |  |
Investment securities HTM |  |
Number of held to maturity securities in a continuous unrealized loss position | security | 0 |

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