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Investment Securities - Schedule of Investments within the Available for Sale Portfolio that had Unrealized Losses (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value |  |
Less than 12 months | $ 883 | $ 1,614
12 months or longer | 5,645 | 5,855
Total fair value | 6,528 | 7,469
Unrealized Losses |  |
Less than 12 months | (2) | (18)
12 months or longer | (748) | (1,017)
Total unrealized losses | (750) | (1,035)
Government agency issued MBS |  |
Fair Value |  |
Less than 12 months | 146 | 663
12 months or longer | 2,885 | 2,992
Total fair value | 3,031 | 3,655
Unrealized Losses |  |
Less than 12 months | (1) | (9)
12 months or longer | (363) | (513)
Total unrealized losses | (364) | (522)
Government agency issued CMO |  |
Fair Value |  |
Less than 12 months | 407 | 675
12 months or longer | 1,720 | 1,744
Total fair value | 2,127 | 2,419
Unrealized Losses |  |
Less than 12 months | 0 | (2)
12 months or longer | (239) | (310)
Total unrealized losses | (239) | (312)
Other U.S. government agencies |  |
Fair Value |  |
Less than 12 months | 300 | 210
12 months or longer | 801 | 863
Total fair value | 1,101 | 1,073
Unrealized Losses |  |
Less than 12 months | (1) | (6)
12 months or longer | (116) | (155)
Total unrealized losses | (117) | (161)
States and municipalities |  |
Fair Value |  |
Less than 12 months | 30 | 66
12 months or longer | 239 | 256
Total fair value | 269 | 322
Unrealized Losses |  |
Less than 12 months | 0 | (1)
12 months or longer | (30) | (39)
Total unrealized losses | $ (30) | $ (40)

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