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Securities - Schedule of Available for Sale Securities in an Unrealized Loss Position (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
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Held-to-maturity securities: |  |
Temporarily impaired securities, fair value, less than 12 months | $ 2,004 | $ 15,728
Temporarily impaired securities, gross unrealized losses, less than 12 months | 11 | 281
Temporarily impaired securities, fair value, 12 months or longer | 22,705 | 22,010
Temporarily impaired securities, gross unrealized losses, 12 months or longer | 2,836 | 3,906
Temporarily impaired securities, fair value | 24,709 | 37,738
Temporarily impaired securities, gross unrealized losses | 2,847 | 4,187
U.S. Treasury, agencies and corporations |  |
Securities available for sale: |  |
Fair value, less than 12 months | 0 | 3,647
Gross unrealized losses, less than 12 months | 0 | 8
Fair value, 12 months or longer | 525 | 508
Gross unrealized losses, 12 months or longer | 17 | 36
Fair value, total | 525 | 4,155
Gross unrealized losses, total | 17 | 44
Agency residential collateralized mortgage obligations |  |
Securities available for sale: |  |
Fair value, less than 12 months | 0 | 91
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 7,677 | 8,108
Gross unrealized losses, 12 months or longer | 1,708 | 2,193
Fair value, total | 7,677 | 8,199
Gross unrealized losses, total | 1,708 | 2,193
Held-to-maturity securities: |  |
Fair value, less than 12 months | 240 | 569
Gross unrealized losses, less than 12 months | 2 | 18
Fair value, 12 months or longer | 3,023 | 3,387
Gross unrealized losses, 12 months or longer | 174 | 314
Fair value, total | 3,263 | 3,956
Gross unrealized losses, total | 176 | 332
Agency residential mortgage-backed securities |  |
Securities available for sale: |  |
Fair value, less than 12 months | 1,226 | 11,364
Gross unrealized losses, less than 12 months | 7 | 254
Fair value, 12 months or longer | 5,583 | 3,145
Gross unrealized losses, 12 months or longer | 450 | 618
Fair value, total | 6,809 | 14,509
Gross unrealized losses, total | 457 | 872
Held-to-maturity securities: |  |
Fair value, less than 12 months | 526 | 0
Gross unrealized losses, less than 12 months | 2 | 0
Fair value, 12 months or longer | 125 | 134
Gross unrealized losses, 12 months or longer | 11 | 17
Fair value, total | 651 | 134
Gross unrealized losses, total | 13 | 17
Agency commercial mortgage-backed securities |  |
Securities available for sale: |  |
Fair value, less than 12 months | 7 | 50
Gross unrealized losses, less than 12 months | 0 | 1
Fair value, 12 months or longer | 3,777 | 4,360
Gross unrealized losses, 12 months or longer | 335 | 516
Fair value, total | 3,784 | 4,410
Gross unrealized losses, total | 335 | 517
Held-to-maturity securities: |  |
Fair value, less than 12 months | 0 | 0
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 1,914 | 2,060
Gross unrealized losses, 12 months or longer | 139 | 203
Fair value, total | 1,914 | 2,060
Gross unrealized losses, total | 139 | 203
Asset-backed securities |  |
Held-to-maturity securities: |  |
Fair value, less than 12 months | 0 | 0
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 75 | 300
Gross unrealized losses, 12 months or longer | 2 | 8
Fair value, total | 75 | 300
Gross unrealized losses, total | 2 | 8
Other securities |  |
Held-to-maturity securities: |  |
Fair value, less than 12 months | 5 | 7
Gross unrealized losses, less than 12 months | 0 | 0
Fair value, 12 months or longer | 6 | 8
Gross unrealized losses, 12 months or longer | 0 | 1
Fair value, total | 11 | 15
Gross unrealized losses, total | $ 0 | $ 1

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