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Investment Securities - Schedule Of Investments Within The Available For Sale Portfolio That Had Unrealized Losses (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Unrealized Losses |  |
Fair value, less than 12 months | $ 300 | $ 4,554
Unrealized losses, less than 12 months | (4) | (487)
Fair value, 12 months or longer | 7,699 | 4,037
Unrealized loss, 12 months or longer | (1,108) | (801)
Fair value, total | 7,999 | 8,591
Unrealized losses, total | (1,112) | (1,288)
Government agency issued MBS |  |
Unrealized Losses |  |
Fair value, less than 12 months | 140 | 2,314
Unrealized losses, less than 12 months | (2) | (249)
Fair value, 12 months or longer | 4,231 | 2,350
Unrealized loss, 12 months or longer | (577) | (446)
Fair value, total | 4,371 | 4,664
Unrealized losses, total | (579) | (695)
Government agency issued CMO |  |
Unrealized Losses |  |
Fair value, less than 12 months | 32 | 1,104
Unrealized losses, less than 12 months | 0 | (123)
Fair value, 12 months or longer | 2,098 | 1,209
Unrealized loss, 12 months or longer | (341) | (246)
Fair value, total | 2,130 | 2,313
Unrealized losses, total | (341) | (369)
Other U.S. government agencies |  |
Unrealized Losses |  |
Fair value, less than 12 months | 114 | 643
Unrealized losses, less than 12 months | (2) | (67)
Fair value, 12 months or longer | 905 | 424
Unrealized loss, 12 months or longer | (149) | (95)
Fair value, total | 1,019 | 1,067
Unrealized losses, total | (151) | (162)
States and municipalities |  |
Unrealized Losses |  |
Fair value, less than 12 months | 14 | 493
Unrealized losses, less than 12 months | 0 | (48)
Fair value, 12 months or longer | 465 | 54
Unrealized loss, 12 months or longer | (41) | (14)
Fair value, total | 479 | 547
Unrealized losses, total | $ (41) | $ (62)

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