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Fair Value (Recurring Fair Value Measurements) (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | $ 298,737 | $ 281,043
Equity securities | 790 | 712
Unit-linked and FVO securities | 11,694 | 10,672
Short-term investments | 5,300 | 5,156
Derivative assets | 7,477 | 8,212
Market risk benefits, at estimated fair value | 352 | 372
Separate account assets | 143,175 | 139,504
Liabilities [Abstract] |  |
Derivative liabilities | 7,543 | 7,259
Embedded derivatives within liability host contracts | (90) | 9
Market risk benefits, at estimated fair value | 2,709 | 2,581
Separate account liabilities | 143,175 | 139,504
Recurring |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 298,737 | 281,043
Equity securities | 790 | 712
Unit-linked and FVO securities | 11,694 | 10,672
Short-term investments | 5,012 | 4,834
Other investments | 1,261 | 1,110
Derivative assets | 7,477 | 8,212
Market risk benefits, at estimated fair value | 352 | 372
Reinsured MRB Assets | 15 | 12
Separate account assets | 143,175 | 139,504
Total assets | 468,513 | 446,471
Liabilities [Abstract] |  |
Derivative liabilities | 7,543 | 7,259
Embedded derivatives within liability host contracts | (90) | 9
Market risk benefits, at estimated fair value | 2,709 | 2,581
Total liabilities | 10,169 | 9,851
Recurring | Interest rate |  |
Assets [Abstract] |  |
Derivative assets | 3,002 | 3,005
Liabilities [Abstract] |  |
Derivative liabilities | 3,612 | 3,464
Recurring | Foreign currency exchange rate contracts |  |
Assets [Abstract] |  |
Derivative assets | 3,961 | 4,709
Liabilities [Abstract] |  |
Derivative liabilities | 3,290 | 3,452
Recurring | Credit |  |
Assets [Abstract] |  |
Derivative assets | 243 | 215
Liabilities [Abstract] |  |
Derivative liabilities | 68 | 72
Recurring | Equity market contracts |  |
Assets [Abstract] |  |
Derivative assets | 271 | 283
Liabilities [Abstract] |  |
Derivative liabilities | 573 | 271
Recurring | Separate account liabilities |  |
Liabilities [Abstract] |  |
Separate account liabilities | 7 | 2
Recurring | U.S. corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 82,533 | 79,374
Recurring | Foreign corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 59,243 | 53,759
Recurring | Foreign government |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 42,482 | 40,250
Recurring | RMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 41,075 | 34,421
Recurring | U.S. government and agency |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 32,626 | 33,428
Recurring | ABS & CLO |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 21,224 | 20,591
Recurring | Municipals |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,937 | 9,873
Recurring | CMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,617 | 9,347
Recurring | Level 1 |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 15,315 | 16,675
Equity securities | 461 | 415
Unit-linked and FVO securities | 7,964 | 7,306
Short-term investments | 3,550 | 4,127
Other investments | 45 | 37
Derivative assets | 14 | 11
Market risk benefits, at estimated fair value | 0 | 0
Reinsured MRB Assets | 0 | 0
Separate account assets | 69,906 | 63,979
Total assets | 97,255 | 92,550
Liabilities [Abstract] |  |
Derivative liabilities | 21 | 7
Embedded derivatives within liability host contracts | 0 | 0
Market risk benefits, at estimated fair value | 0 | 0
Total liabilities | 21 | 7
Recurring | Level 1 | Interest rate |  |
Assets [Abstract] |  |
Derivative assets | 13 | 1
Liabilities [Abstract] |  |
Derivative liabilities | 1 | 1
Recurring | Level 1 | Foreign currency exchange rate contracts |  |
Assets [Abstract] |  |
Derivative assets | 0 | 1
Liabilities [Abstract] |  |
Derivative liabilities | 0 | 0
Recurring | Level 1 | Credit |  |
Assets [Abstract] |  |
Derivative assets | 0 | 0
Liabilities [Abstract] |  |
Derivative liabilities | 0 | 0
Recurring | Level 1 | Equity market contracts |  |
Assets [Abstract] |  |
Derivative assets | 1 | 9
Liabilities [Abstract] |  |
Derivative liabilities | 20 | 6
Recurring | Level 1 | Separate account liabilities |  |
Liabilities [Abstract] |  |
Separate account liabilities | 0 | 0
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 | RMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 103 | 0
Recurring | Level 1 | U.S. government and agency |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 15,212 | 16,675
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 | 251,029 | 229,176
Equity securities | 77 | 61
Unit-linked and FVO securities | 2,465 | 2,176
Short-term investments | 1,454 | 702
Other investments | 63 | 63
Derivative assets | 7,442 | 8,184
Market risk benefits, at estimated fair value | 0 | 0
Reinsured MRB Assets | 0 | 0
Separate account assets | 72,292 | 74,535
Total assets | 334,822 | 314,897
Liabilities [Abstract] |  |
Derivative liabilities | 7,517 | 7,240
Embedded derivatives within liability host contracts | 0 | 0
Market risk benefits, at estimated fair value | 0 | 0
Total liabilities | 7,524 | 7,242
Recurring | Level 2 | Interest rate |  |
Assets [Abstract] |  |
Derivative assets | 2,989 | 3,004
Liabilities [Abstract] |  |
Derivative liabilities | 3,611 | 3,463
Recurring | Level 2 | Foreign currency exchange rate contracts |  |
Assets [Abstract] |  |
Derivative assets | 3,940 | 4,694
Liabilities [Abstract] |  |
Derivative liabilities | 3,285 | 3,440
Recurring | Level 2 | Credit |  |
Assets [Abstract] |  |
Derivative assets | 243 | 215
Liabilities [Abstract] |  |
Derivative liabilities | 68 | 72
Recurring | Level 2 | Equity market contracts |  |
Assets [Abstract] |  |
Derivative assets | 270 | 271
Liabilities [Abstract] |  |
Derivative liabilities | 553 | 265
Recurring | Level 2 | Separate account liabilities |  |
Liabilities [Abstract] |  |
Separate account liabilities | 7 | 2
Recurring | Level 2 | U.S. corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 70,170 | 67,333
Recurring | Level 2 | Foreign corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 42,969 | 39,295
Recurring | Level 2 | Foreign government |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 42,426 | 40,209
Recurring | Level 2 | RMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 39,024 | 32,771
Recurring | Level 2 | U.S. government and agency |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 17,414 | 16,753
Recurring | Level 2 | ABS & CLO |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 19,895 | 14,755
Recurring | Level 2 | Municipals |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,937 | 9,866
Recurring | Level 2 | CMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 9,194 | 8,194
Recurring | Level 3 |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 32,393 | 35,192
Equity securities | 252 | 236
Unit-linked and FVO securities | 1,265 | 1,190
Short-term investments | 8 | 5
Other investments | 1,153 | 1,010
Derivative assets | 21 | 17
Market risk benefits, at estimated fair value | 352 | 372
Reinsured MRB Assets | 15 | 12
Separate account assets | 977 | 990
Total assets | 36,436 | 39,024
Liabilities [Abstract] |  |
Derivative liabilities | 5 | 12
Embedded derivatives within liability host contracts | (90) | 9
Market risk benefits, at estimated fair value | 2,709 | 2,581
Total liabilities | 2,624 | 2,602
Recurring | Level 3 | Interest rate |  |
Assets [Abstract] |  |
Derivative assets | 0 | 0
Liabilities [Abstract] |  |
Derivative liabilities | 0 | 0
Recurring | Level 3 | Foreign currency exchange rate contracts |  |
Assets [Abstract] |  |
Derivative assets | 21 | 14
Liabilities [Abstract] |  |
Derivative liabilities | 5 | 12
Recurring | Level 3 | Credit |  |
Assets [Abstract] |  |
Derivative assets | 0 | 0
Liabilities [Abstract] |  |
Derivative liabilities | 0 | 0
Recurring | Level 3 | Equity market contracts |  |
Assets [Abstract] |  |
Derivative assets | 0 | 3
Liabilities [Abstract] |  |
Derivative liabilities | 0 | 0
Recurring | Level 3 | Separate account liabilities |  |
Liabilities [Abstract] |  |
Separate account liabilities | 0 | 0
Recurring | Level 3 | U.S. corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 12,363 | 12,041
Recurring | Level 3 | Foreign corporate |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 16,274 | 14,464
Recurring | Level 3 | Foreign government |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 56 | 41
Recurring | Level 3 | RMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 1,948 | 1,650
Recurring | Level 3 | U.S. government and agency |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 0
Recurring | Level 3 | ABS & CLO |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 1,329 | 5,836
Recurring | Level 3 | Municipals |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 0 | 7
Recurring | Level 3 | CMBS |  |
Assets [Abstract] |  |
Estimated Fair Value of Fixed Maturity Securities AFS | 423 | 1,153
Other limited partnership interests | Recurring |  |
Assets [Abstract] |  |
Investments, fair value | $ 47 | $ 50

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