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Investment Securities - Schedule of Investment Portfolio (Details) - USD ($) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024
Available-for-sale securities |  |  |
Amortized cost | $ 25,660,000,000 |  | $ 26,810,000,000
Gross unrealized gains | 67,000,000 |  | 5,000,000
Gross unrealized losses | (3,043,000,000) |  | (4,405,000,000)
Fair value | 22,684,000,000 |  | 22,410,000,000
Held-to-maturity securities |  |  |
Amortized cost | 4,433,000,000 |  | 4,346,000,000
Gross unrealized gains | 223,000,000 |  | 143,000,000
Gross unrealized losses | (163,000,000) |  | (196,000,000)
Fair value | 4,493,000,000 |  | 4,293,000,000
Debt securities, available-for-sale, accrued interest receivable | $ 81,000,000 |  | $ 73,000,000
Debt securities, available-for-sale, accrued interest, after allowance for credit loss, statement of financial position [extensible enumeration] | Other assets |  | Other assets
Debt securities, available-for-sale, allowance for credit loss, excluding accrued interest | $ 0 |  | $ 0
Debt securities, held-to-maturity, allowance for credit loss, excluding accrued interest | 0 |  | 0
Debt securities, held-to-maturity, accrued interest receivable | 13,000,000 |  | 12,000,000
Amortized cost basis in amount sold |  | $ 4,600,000,000 |
Gross proceeds received and receivable from sale of lower-yielding available-for-sale securities | 4,100,000,000 |  |
Pre-tax loss | 495,000,000 |  |
Operating Segments | Insurance operations |  |  |
Held-to-maturity securities |  |  |
Deposited securities | 13,000,000 |  | 13,000,000
Asset Pledged as Collateral with Right |  |  |
Available-for-sale securities |  |  |
Fair value | 3,700,000,000 |  | 3,400,000,000
Held-to-maturity securities |  |  |
Securities with the right to sell or pledge | 945,000,000 |  | 439,000,000
Asset Pledged as Collateral with Right | Federal Home Loan Bank advances |  |  |
Held-to-maturity securities |  |  |
Securities with the right to sell or pledge | 2,800,000,000 |  | 2,900,000,000
U.S. Treasury and federal agencies |  |  |
Available-for-sale securities |  |  |
Amortized cost | 2,230,000,000 |  | 2,073,000,000
Gross unrealized gains | 19,000,000 |  | 0
Gross unrealized losses | (55,000,000) |  | (200,000,000)
Fair value | 2,194,000,000 |  | 1,873,000,000
U.S. States and political subdivisions |  |  |
Available-for-sale securities |  |  |
Amortized cost | 634,000,000 |  | 704,000,000
Gross unrealized gains | 0 |  | 0
Gross unrealized losses | (80,000,000) |  | (87,000,000)
Fair value | 554,000,000 |  | 617,000,000
Foreign government |  |  |
Available-for-sale securities |  |  |
Amortized cost | 205,000,000 |  | 198,000,000
Gross unrealized gains | 2,000,000 |  | 1,000,000
Gross unrealized losses | (3,000,000) |  | (5,000,000)
Fair value | 204,000,000 |  | 194,000,000
Agency mortgage-backed residential |  |  |
Available-for-sale securities |  |  |
Amortized cost | 14,965,000,000 |  | 16,765,000,000
Gross unrealized gains | 12,000,000 |  | 0
Gross unrealized losses | (2,155,000,000) |  | (3,112,000,000)
Fair value | 12,822,000,000 |  | 13,653,000,000
Held-to-maturity securities |  |  |
Amortized cost | 1,284,000,000 |  | 935,000,000
Gross unrealized gains | 5,000,000 |  | 0
Gross unrealized losses | (163,000,000) |  | (196,000,000)
Fair value | 1,126,000,000 |  | 739,000,000
Hedged asset, fair value hedge, cumulative increase (decrease) | 53,000,000 |  |
Hedged liability, fair value hedge, cumulative increase (decrease) |  |  | 72,000,000
Mortgage-backed residential |  |  |
Available-for-sale securities |  |  |
Amortized cost | 235,000,000 |  | 249,000,000
Gross unrealized gains | 0 |  | 0
Gross unrealized losses | (35,000,000) |  | (43,000,000)
Fair value | 200,000,000 |  | 206,000,000
Held-to-maturity securities |  |  |
Amortized cost | 3,091,000,000 |  | 3,323,000,000
Gross unrealized gains | 217,000,000 |  | 142,000,000
Gross unrealized losses | 0 |  | 0
Fair value | 3,308,000,000 |  | 3,465,000,000
Agency mortgage-backed commercial |  |  |
Available-for-sale securities |  |  |
Amortized cost | 5,415,000,000 |  | 4,819,000,000
Gross unrealized gains | 14,000,000 |  | 1,000,000
Gross unrealized losses | (647,000,000) |  | (836,000,000)
Fair value | 4,782,000,000 |  | 3,984,000,000
Held-to-maturity securities |  |  |
Hedged asset, fair value hedge, cumulative increase (decrease) | 40,000,000 |  |
Hedged liability, fair value hedge, cumulative increase (decrease) |  |  | 34,000,000
Asset-backed |  |  |
Available-for-sale securities |  |  |
Amortized cost | 25,000,000 |  | 131,000,000
Gross unrealized gains | 0 |  | 0
Gross unrealized losses | 0 |  | (2,000,000)
Fair value | 25,000,000 |  | 129,000,000
Held-to-maturity securities |  |  |
Amortized cost | 58,000,000 |  | 88,000,000
Gross unrealized gains | 1,000,000 |  | 1,000,000
Gross unrealized losses | 0 |  | 0
Fair value | 59,000,000 |  | 89,000,000
Corporate debt |  |  |
Available-for-sale securities |  |  |
Amortized cost | 1,951,000,000 |  | 1,871,000,000
Gross unrealized gains | 20,000,000 |  | 3,000,000
Gross unrealized losses | (68,000,000) |  | (120,000,000)
Fair value | $ 1,903,000,000 |  | $ 1,754,000,000

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