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Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022 | Jan. 01, 2021 | Dec. 31, 2020
--- | --- | --- | --- | ---
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | $ 281,412 | $ 276,780 |  |
Equity securities | 757 | 1,684 |  |
Unit-linked and FVO securities (1) | 10,331 | 9,668 |  |
Short-term investments (2) | 6,045 | 4,935 |  |
Derivative assets | 8,737 | 11,411 |  |
Market risk benefits, at estimated fair value | 286 | 280 |  |
Reinsured MRB assets |  |  | $ 51 | $ 0
Separate account assets | 144,634 | 146,038 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 6,298 | 6,975 |  |
Embedded derivatives within liability host contracts (7) | 93 | 17 |  |
Market risk benefits, at estimated fair value | 3,179 | 3,763 | $ 7,901 |
Separate account liabilities | 144,634 | 146,038 |  |
Recurring |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 281,412 | 276,780 |  |
Equity securities | 757 | 1,684 |  |
Unit-linked and FVO securities (1) | 10,331 | 9,668 |  |
Short-term investments (2) | 5,797 | 4,573 |  |
Other investments | 1,386 | 1,132 |  |
Derivative assets | 8,737 | 11,411 |  |
Market risk benefits, at estimated fair value | 286 | 280 |  |
Reinsured MRB assets | 18 | 23 |  |
Separate account assets | 144,634 | 146,038 |  |
Total assets (6) | 453,358 | 451,589 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 6,298 | 6,975 |  |
Embedded derivatives within liability host contracts (7) | 93 | 17 |  |
Market risk benefits, at estimated fair value | 3,179 | 3,763 |  |
Total liabilities | 9,578 | 10,796 |  |
Recurring | Interest rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 3,675 | 4,572 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 2,984 | 3,558 |  |
Recurring | Foreign currency exchange rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 4,418 | 5,888 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 2,744 | 2,870 |  |
Recurring | Credit contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 236 | 151 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 84 | 107 |  |
Recurring | Equity market contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 408 | 800 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 486 | 440 |  |
Recurring | Derivative Liabilities Within Separate Accounts |  |  |  |
Liabilities [Abstract] |  |  |  |
Separate account liabilities | 8 | 41 |  |
Recurring | U.S. corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 80,717 | 80,030 |  |
Recurring | Foreign corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 55,444 | 52,572 |  |
Recurring | Foreign government |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 45,489 | 46,747 |  |
Recurring | U.S. government and agency |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 32,252 | 32,229 |  |
Recurring | RMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 29,096 | 26,165 |  |
Recurring | ABS & CLO |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 17,294 | 16,822 |  |
Recurring | Municipals |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 11,171 | 12,152 |  |
Recurring | CMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,949 | 10,063 |  |
Recurring | Level 1 |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 15,330 | 15,959 |  |
Equity securities | 429 | 1,293 |  |
Unit-linked and FVO securities (1) | 7,520 | 7,101 |  |
Short-term investments (2) | 5,103 | 3,830 |  |
Other investments | 48 | 0 |  |
Derivative assets | 11 | 18 |  |
Market risk benefits, at estimated fair value | 0 | 0 |  |
Reinsured MRB assets | 0 | 0 |  |
Separate account assets | 66,229 | 65,107 |  |
Total assets (6) | 94,670 | 93,308 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 16 | 5 |  |
Embedded derivatives within liability host contracts (7) | 0 | 0 |  |
Market risk benefits, at estimated fair value | 0 | 0 |  |
Total liabilities | 20 | 13 |  |
Recurring | Level 1 | Interest rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 1 | 2 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 5 | 1 |  |
Recurring | Level 1 | Foreign currency exchange rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 2 | 8 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 0 | 0 |  |
Recurring | Level 1 | Credit contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 0 | 0 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 0 | 0 |  |
Recurring | Level 1 | Equity market contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 8 | 8 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 11 | 4 |  |
Recurring | Level 1 | Derivative Liabilities Within Separate Accounts |  |  |  |
Liabilities [Abstract] |  |  |  |
Separate account liabilities | 4 | 8 |  |
Recurring | Level 1 | U.S. corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 1 | Foreign corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 1 | Foreign government |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 1 | U.S. government and agency |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 15,327 | 15,955 |  |
Recurring | Level 1 | RMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 3 | 4 |  |
Recurring | Level 1 | ABS & CLO |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 1 | Municipals |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 1 | CMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 2 |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 233,135 | 232,048 |  |
Equity securities | 79 | 132 |  |
Unit-linked and FVO securities (1) | 1,708 | 1,780 |  |
Short-term investments (2) | 667 | 686 |  |
Other investments | 363 | 206 |  |
Derivative assets | 8,688 | 11,094 |  |
Market risk benefits, at estimated fair value | 0 | 0 |  |
Reinsured MRB assets | 0 | 0 |  |
Separate account assets | 77,258 | 79,703 |  |
Total assets (6) | 321,898 | 325,649 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 6,101 | 6,501 |  |
Embedded derivatives within liability host contracts (7) | 0 | 0 |  |
Market risk benefits, at estimated fair value | 0 | 0 |  |
Total liabilities | 6,105 | 6,516 |  |
Recurring | Level 2 | Interest rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 3,674 | 4,570 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 2,805 | 3,153 |  |
Recurring | Level 2 | Foreign currency exchange rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 4,393 | 5,670 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 2,737 | 2,820 |  |
Recurring | Level 2 | Credit contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 228 | 69 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 84 | 92 |  |
Recurring | Level 2 | Equity market contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 393 | 785 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 475 | 436 |  |
Recurring | Level 2 | Derivative Liabilities Within Separate Accounts |  |  |  |
Liabilities [Abstract] |  |  |  |
Separate account liabilities | 4 | 15 |  |
Recurring | Level 2 | U.S. corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 67,003 | 67,578 |  |
Recurring | Level 2 | Foreign corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 40,813 | 40,623 |  |
Recurring | Level 2 | Foreign government |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 45,438 | 46,644 |  |
Recurring | Level 2 | U.S. government and agency |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 16,925 | 16,274 |  |
Recurring | Level 2 | RMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 27,495 | 24,515 |  |
Recurring | Level 2 | ABS & CLO |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 15,191 | 14,895 |  |
Recurring | Level 2 | Municipals |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 11,171 | 12,152 |  |
Recurring | Level 2 | CMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,099 | 9,367 |  |
Recurring | Level 3 |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 32,947 | 28,773 |  |
Equity securities | 249 | 259 |  |
Unit-linked and FVO securities (1) | 1,103 | 787 |  |
Short-term investments (2) | 27 | 57 |  |
Other investments | 975 | 926 |  |
Derivative assets | 38 | 299 |  |
Market risk benefits, at estimated fair value | 286 | 280 |  |
Reinsured MRB assets | 18 | 23 |  |
Separate account assets | 1,147 | 1,228 |  |
Total assets (6) | 36,790 | 32,632 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 181 | 469 |  |
Embedded derivatives within liability host contracts (7) | 93 | 17 |  |
Market risk benefits, at estimated fair value | 3,179 | 3,763 |  |
Total liabilities | 3,453 | 4,267 |  |
Recurring | Level 3 | Interest rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 0 | 0 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 174 | 404 |  |
Recurring | Level 3 | Foreign currency exchange rate contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 23 | 210 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 7 | 50 |  |
Recurring | Level 3 | Credit contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 8 | 82 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 0 | 15 |  |
Recurring | Level 3 | Equity market contracts |  |  |  |
Assets [Abstract] |  |  |  |
Derivative assets | 7 | 7 |  |
Liabilities [Abstract] |  |  |  |
Derivative liabilities | 0 | 0 |  |
Recurring | Level 3 | Derivative Liabilities Within Separate Accounts |  |  |  |
Liabilities [Abstract] |  |  |  |
Separate account liabilities | 0 | 18 |  |
Recurring | Level 3 | U.S. corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 13,714 | 12,452 |  |
Recurring | Level 3 | Foreign corporate |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 14,631 | 11,949 |  |
Recurring | Level 3 | Foreign government |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 51 | 103 |  |
Recurring | Level 3 | U.S. government and agency |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 3 | RMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 1,598 | 1,646 |  |
Recurring | Level 3 | ABS & CLO |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 2,103 | 1,927 |  |
Recurring | Level 3 | Municipals |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0 |  |
Recurring | Level 3 | CMBS |  |  |  |
Assets [Abstract] |  |  |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 850 | 696 |  |
Other limited partnership interests | Recurring |  |  |  |
Assets [Abstract] |  |  |  |
Investments, Fair Value Disclosure | $ 52 | $ 65 |  |

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