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Securities - Schedule of Available for Sale Securities in an Unrealized Loss Position (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Held-to-maturity securities: |  |
Temporarily impaired securities, fair value, less than 12 months | $ 2,055 | $ 13,776
Temporarily impaired securities, gross unrealized losses, less than 12 months | 79 | 1,140
Temporarily impaired securities, fair value, 12 months or longer | 41,416 | 32,405
Temporarily impaired securities, gross unrealized losses, 12 months or longer | 5,970 | 5,900
Temporarily impaired securities, fair value | 43,471 | 46,181
Temporarily impaired securities, gross unrealized losses | 6,049 | 7,040
U.S. Treasury, agencies and corporations |  |
Securities available for sale: |  |
Fair value, less than 12 months | 0 | 494
Gross unrealized losses, less than 12 months | 0 | 48
Fair value, 12 months or longer | 8,532 | 8,920
Gross unrealized losses, 12 months or longer | 280 | 581
Fair value | 8,532 | 9,414
Gross unrealized losses | 280 | 629
Agency residential collateralized mortgage obligations |  |
Securities available for sale: |  |
Fair value, less than 12 months | 0 | 3,114
Gross unrealized losses, less than 12 months | 0 | 377
Fair value, 12 months or longer | 14,979 | 13,317
Gross unrealized losses, 12 months or longer | 3,437 | 3,370
Fair value | 14,979 | 16,431
Gross unrealized losses | 3,437 | 3,747
Held-to-maturity securities: |  |
Fair value, less than 12 months | 1,123 | 2,659
Gross unrealized losses, less than 12 months | 30 | 178
Fair value, 12 months or longer | 3,070 | 726
Gross unrealized losses, 12 months or longer | 253 | 105
Fair value | 4,193 | 3,385
Gross unrealized losses | 283 | 283
Agency residential mortgage-backed securities |  |
Securities available for sale: |  |
Fair value, less than 12 months | 24 | 579
Gross unrealized losses, less than 12 months | 0 | 31
Fair value, 12 months or longer | 3,562 | 3,338
Gross unrealized losses, 12 months or longer | 600 | 665
Fair value | 3,586 | 3,917
Gross unrealized losses | 600 | 696
Held-to-maturity securities: |  |
Fair value, less than 12 months | 0 | 165
Gross unrealized losses, less than 12 months | 0 | 16
Fair value, 12 months or longer | 152 | 0
Gross unrealized losses, 12 months or longer | 13 | 0
Fair value | 152 | 165
Gross unrealized losses | 13 | 16
Agency commercial mortgage-backed securities |  |
Securities available for sale: |  |
Fair value, less than 12 months | 891 | 4,511
Gross unrealized losses, less than 12 months | 49 | 282
Fair value, 12 months or longer | 8,201 | 4,791
Gross unrealized losses, 12 months or longer | 1,154 | 1,083
Fair value | 9,092 | 9,302
Gross unrealized losses | 1,203 | 1,365
Held-to-maturity securities: |  |
Fair value, less than 12 months | 0 | 2,243
Gross unrealized losses, less than 12 months | 0 | 208
Fair value, 12 months or longer | 2,199 | 0
Gross unrealized losses, 12 months or longer | 204 | 0
Fair value | 2,199 | 2,243
Gross unrealized losses | 204 | 208
Asset-backed securities |  |
Held-to-maturity securities: |  |
Fair value, less than 12 months | 0 | 1
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 709 | 1,309
Gross unrealized losses, 12 months or longer | 29 | 96
Fair value | 709 | 1,310
Gross unrealized losses | 29 | 96
Other securities |  |
Held-to-maturity securities: |  |
Fair value, less than 12 months | 17 | 10
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 12 | 4
Gross unrealized losses, 12 months or longer | 0 | 0
Fair value | 29 | 14
Gross unrealized losses | $ 0 | $ 0

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