| **Fair Value (Quantitative information about significant unobservable inputs in the fair value measurement of level 3 assets) (Details) $ in Millions** | Jun. 30, 2024 USD ($) | Dec. 31, 2023 USD ($) |
|---------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------|-----------------------|
| **Fair Value Inputs, Assets, Quantitative Information [Line Items]**                                                                                    |                  |                  |
| Estimated fair value                                                                                                                                    | $ 42,643              | $ 43,116              |
| Fixed maturity securities | Discounted cash flow                                                                                                        |                  |                  |
| **Fair Value Inputs, Assets, Quantitative Information [Line Items]**                                                                                    |                  |                  |
| Estimated fair value                                                                                                                                    | $ 1,571               | $ 1,495               |
| Credit spread | Discounted cash flow | Minimum                                                                                                          |                  |                  |
| **Fair Value Inputs, Assets, Quantitative Information [Line Items]**                                                                                    |                  |                  |
| Debt securities, available-for-sale, measurement Input                                                                                                  | 0.01                  | 0.01                  |
| Credit spread | Discounted cash flow | Maximum                                                                                                          |                  |                  |
| **Fair Value Inputs, Assets, Quantitative Information [Line Items]**                                                                                    |                  |                  |
| Debt securities, available-for-sale, measurement Input                                                                                                  | 0.06                  | 0.07                  |
| Credit spread | Discounted cash flow | Weighted Average                                                                                                 |                  |                  |
| **Fair Value Inputs, Assets, Quantitative Information [Line Items]**                                                                                    |                  |                  |
| Debt securities, available-for-sale, measurement Input                                                                                                  | 0.02                  | 0.02                  |

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Fair value portion of asset recognized for present right to economic benefit.
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