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Investments (Tables) | 9 Months Ended
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Sep. 30, 2025
Investments [Abstract] |
Amortized Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value of Fixed-maturity Securities | The following table provides amortized cost, gross unrealized gains, gross unrealized losses and fair value for our fixed-maturity and short-term investments:
(Dollars in millions) |  | Amortized cost |  | Gross unrealized |  | Fair value
At September 30, 2025 |  |  | gains |  | losses |
Fixed-maturity: |  |  |  |  |  |  |  |
Corporate |  | $ | 9,385 |  |  | $ | 171 |  |  | $ | 193 |  |  | $ | 9,363 |
States, municipalities and political subdivisions |  | 5,043 |  |  | 24 |  |  | 221 |  |  | 4,846 |
Government-sponsored enterprises |  | 2,348 |  |  | 3 |  |  | 5 |  |  | 2,346 |
Asset-backed |  | 776 |  |  | 11 |  |  | 9 |  |  | 778 |
United States government |  | 272 |  |  | 3 |  |  | 1 |  |  | 274 |
Foreign government |  | 23 |  |  | — |  |  | — |  |  | 23 |
Total fixed-maturity |  | 17,847 |  |  | 212 |  |  | 429 |  |  | 17,630 |
Short-term |  | 149 |  |  | — |  |  | — |  |  | 149 |
Total fixed-maturity and short-term investments |  | $ | 17,996 |  |  | $ | 212 |  |  | $ | 429 |  |  | $ | 17,779 |
At December 31, 2024 |  |  |  |  |  |  |  |
Fixed-maturity: |  |  |  |  |  |  |  |
Corporate |  | $ | 8,652 |  |  | $ | 61 |  |  | $ | 333 |  |  | $ | 8,380 |
States, municipalities and political subdivisions |  | 4,976 |  |  | 15 |  |  | 270 |  |  | 4,721 |
Government-sponsored enterprises |  | 2,282 |  |  | 1 |  |  | 9 |  |  | 2,274 |
Asset-backed |  | 567 |  |  | 1 |  |  | 17 |  |  | 551 |
United States government |  | 228 |  |  | — |  |  | 2 |  |  | 226 |
Foreign government |  | 30 |  |  | — |  |  | — |  |  | 30 |
Total fixed-maturity |  | 16,735 |  |  | 78 |  |  | 631 |  |  | 16,182 |
Short-term |  | 298 |  |  | — |  |  | — |  |  | 298 |
Total fixed-maturity and short-term investments |  | $ | 17,033 |  |  | $ | 78 |  |  | $ | 631 |  |  | $ | 16,480 |
Fair Value and Unrealized Losses by Investment Category and By the Duration of the Securities' Continuous Unrealized Loss Position | The table below provides fair values and gross unrealized losses by investment category and by the duration of the continuous unrealized loss positions:
(Dollars in millions) |  | Less than 12 months |  | 12 months or more |  | Total
At September 30, 2025 |  | Fair value |  | Unrealized losses |  | Fair value |  | Unrealized losses |  | Fair value |  | Unrealized losses
Fixed-maturity: |  |  |  |  |  |  |  |  |  |  |  |
Corporate |  | $ | 793 |  |  | $ | 14 |  |  | $ | 2,887 |  |  | $ | 179 |  |  | $ | 3,680 |  |  | $ | 193 |
States, municipalities and political subdivisions |  | 873 |  |  | 20 |  |  | 2,019 |  |  | 201 |  |  | 2,892 |  |  | 221 |
Government-sponsored enterprises |  | 922 |  |  | 3 |  |  | 488 |  |  | 2 |  |  | 1,410 |  |  | 5 |
Asset-backed |  | 173 |  |  | 4 |  |  | 91 |  |  | 5 |  |  | 264 |  |  | 9 |
United States government |  | — |  |  | — |  |  | 27 |  |  | 1 |  |  | 27 |  |  | 1 |
Foreign government |  | 1 |  |  | — |  |  | — |  |  | — |  |  | 1 |  |  | — |
Total fixed-maturity |  | $ | 2,762 |  |  | $ | 41 |  |  | $ | 5,512 |  |  | $ | 388 |  |  | $ | 8,274 |  |  | $ | 429 |
At December 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |
Fixed-maturity: |  |  |  |  |  |  |  |  |  |  |  |
Corporate |  | $ | 2,815 |  |  | $ | 78 |  |  | $ | 3,634 |  |  | $ | 255 |  |  | $ | 6,449 |  |  | $ | 333 |
States, municipalities and political subdivisions |  | 1,513 |  |  | 25 |  |  | 1,898 |  |  | 245 |  |  | 3,411 |  |  | 270 |
Government-sponsored enterprises |  | 1,876 |  |  | 8 |  |  | 92 |  |  | 1 |  |  | 1,968 |  |  | 9 |
Asset-backed |  | 331 |  |  | 10 |  |  | 96 |  |  | 7 |  |  | 427 |  |  | 17 |
United States government |  | 48 |  |  | — |  |  | 100 |  |  | 2 |  |  | 148 |  |  | 2 |
Foreign government |  | — |  |  | — |  |  | 3 |  |  | — |  |  | 3 |  |  | — |
Total fixed-maturity |  | 6,583 |  |  | 121 |  |  | 5,823 |  |  | 510 |  |  | 12,406 |  |  | 631 |
Short-term |  | 100 |  |  | — |  |  | — |  |  | — |  |  | 100 |  |  | — |
Total fixed-maturity and short-term investments |  | $ | 6,683 |  |  | $ | 121 |  |  | $ | 5,823 |  |  | $ | 510 |  |  | $ | 12,506 |  |  | $ | 631 |
Investments Classified by Contractual Maturity Date | Contractual maturity dates for our fixed-maturity and short-term investments were:
(Dollars in millions) |  | Amortized cost |  | Fair value |  | % of fair value
At September 30, 2025 |  |  |
Maturity dates: |  |  |  |  |  |
Due in one year or less |  | $ | 1,008 |  |  | $ | 1,001 |  |  | 5.6 | %
Due after one year through five years |  | 3,667 |  |  | 3,679 |  |  | 20.7 |
Due after five years through ten years |  | 4,084 |  |  | 4,109 |  |  | 23.1 |
Due after ten years |  | 9,237 |  |  | 8,990 |  |  | 50.6 |
Total |  | $ | 17,996 |  |  | $ | 17,779 |  |  | 100.0 | %
Investment Income, Realized Investment Gains And Losses And Change In Unrealized Investment Gains And Losses | The following table provides investment income and investment gains and losses, net:
(Dollars in millions) | Three months ended September 30, |  | Nine months ended September 30,
| 2025 |  | 2024 |  | 2025 |  | 2024
Investment income: |  |  |  |  |  |  |
Interest | $ | 227 |  |  | $ | 187 |  |  | $ | 651 |  |  | $ | 529 |
Dividends | 69 |  |  | 68 |  |  | 206 |  |  | 209 |
Other | 4 |  |  | 7 |  |  | 16 |  |  | 18 |
Total | 300 |  |  | 262 |  |  | 873 |  |  | 756 |
Less investment expenses | 5 |  |  | 4 |  |  | 13 |  |  | 11 |
Total | $ | 295 |  |  | $ | 258 |  |  | $ | 860 |  |  | $ | 745 |
Investment gains and losses, net: |  |  |  |  |  |  |
Equity securities: |  |  |  |  |  |  |
Investment gains and losses on securities sold, net | $ | (9) |  |  | $ | 24 |  |  | $ | (5) |  |  | $ | 146 |
Unrealized gains and losses on securities still held, net | 855 |  |  | 817 |  |  | 1,259 |  |  | 1,446 |
Subtotal | 846 |  |  | 841 |  |  | 1,254 |  |  | 1,592 |
Fixed-maturity securities: |  |  |  |  |  |  |
Gross realized gains | 2 |  |  | 1 |  |  | 3 |  |  | 5 |
Gross realized losses | (1) |  |  | (87) |  |  | (1) |  |  | (94) |
Change in allowance for credit losses, net | — |  |  | — |  |  | (15) |  |  | (25) |
Subtotal | 1 |  |  | (86) |  |  | (13) |  |  | (114) |
Other | 6 |  |  | 3 |  |  | 18 |  |  | 29 |
Total | $ | 853 |  |  | $ | 758 |  |  | $ | 1,259 |  |  | $ | 1,507 |

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