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v3.25.1

Investments (Securities in a gross unrealized loss position by ratings) (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | $ 25,846 | $ 27,338
Gross Unrealized Losses | 2,767 | 3,040
U.S. Government, Government agencies and Government-sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 2,212 | 2,567
Gross Unrealized Losses | 322 | 373
AAA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 1,453 | 1,830
Gross Unrealized Losses | 265 | 283
AA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 3,981 | 4,257
Gross Unrealized Losses | 701 | 730
A |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 6,254 | 6,340
Gross Unrealized Losses | 527 | 582
BBB |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 10,922 | 11,548
Gross Unrealized Losses | 849 | 980
Non-investment grade |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 1,024 | 796
Gross Unrealized Losses | $ 103 | $ 92

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