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Investment Securities - Schedule of Unrealized Loss on Investments (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Less than 12 months |  |
Fair value | $ 872,000,000 | $ 947,000,000
Unrealized loss | (4,000,000) | (22,000,000)
12 months or longer |  |
Fair value | 16,542,000,000 | 21,069,000,000
Unrealized loss | (3,039,000,000) | (4,383,000,000)
Credit reserves, available-for-sale | 0 | 0
Credit reserves, held-to-maturity | 0 | 0
U.S. Treasury and federal agencies |  |
Less than 12 months |  |
Fair value | 0 | 0
Unrealized loss | 0 | 0
12 months or longer |  |
Fair value | 604,000,000 | 1,873,000,000
Unrealized loss | (55,000,000) | (200,000,000)
U.S. States and political subdivisions |  |
Less than 12 months |  |
Fair value | 53,000,000 | 87,000,000
Unrealized loss | (1,000,000) | (2,000,000)
12 months or longer |  |
Fair value | 426,000,000 | 472,000,000
Unrealized loss | (79,000,000) | (85,000,000)
Foreign government |  |
Less than 12 months |  |
Fair value | 16,000,000 | 40,000,000
Unrealized loss | 0 | 0
12 months or longer |  |
Fair value | 77,000,000 | 112,000,000
Unrealized loss | (3,000,000) | (5,000,000)
Agency mortgage-backed residential |  |
Less than 12 months |  |
Fair value | 547,000,000 | 127,000,000
Unrealized loss | (1,000,000) | (3,000,000)
12 months or longer |  |
Fair value | 10,451,000,000 | 13,518,000,000
Unrealized loss | (2,154,000,000) | (3,109,000,000)
Mortgage-backed residential |  |
Less than 12 months |  |
Fair value | 0 | 0
Unrealized loss | 0 | 0
12 months or longer |  |
Fair value | 200,000,000 | 206,000,000
Unrealized loss | (35,000,000) | (43,000,000)
Agency mortgage-backed commercial |  |
Less than 12 months |  |
Fair value | 191,000,000 | 428,000,000
Unrealized loss | (1,000,000) | (11,000,000)
12 months or longer |  |
Fair value | 3,590,000,000 | 3,445,000,000
Unrealized loss | (646,000,000) | (825,000,000)
Asset-backed |  |
Less than 12 months |  |
Fair value | 0 | 0
Unrealized loss | 0 | 0
12 months or longer |  |
Fair value | 24,000,000 | 124,000,000
Unrealized loss | 0 | (2,000,000)
Corporate debt |  |
Less than 12 months |  |
Fair value | 65,000,000 | 265,000,000
Unrealized loss | (1,000,000) | (6,000,000)
12 months or longer |  |
Fair value | 1,170,000,000 | 1,319,000,000
Unrealized loss | $ (67,000,000) | $ (114,000,000)

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