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v3.23.2

Investments (Securities in a gross unrealized loss position by ratings) (Details) - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | $ 29,612 | $ 29,511
Gross Unrealized Losses | 3,786 | 4,056
U.S. Government, Government agencies and Government-sponsored enterprises |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 2,479 | 2,355
Gross Unrealized Losses | 334 | 337
AAA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 1,662 | 1,559
Gross Unrealized Losses | 283 | 298
AA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 4,404 | 4,327
Gross Unrealized Losses | 746 | 817
A |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 6,937 | 6,615
Gross Unrealized Losses | 703 | 749
BBB |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 12,960 | 13,226
Gross Unrealized Losses | 1,513 | 1,621
Non-investment grade |  |
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | 1,170 | 1,429
Gross Unrealized Losses | $ 207 | $ 234

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