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Derivatives (Primary Risks) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | $ 265,548 | $ 301,234 |
Estimated Fair Value Assets | 8,212 | 8,737 |
Estimated Fair Value Liabilities | 7,259 | 6,298 |
Derivatives Designated as Hedging Instruments [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 66,279 | 64,155 |
Estimated Fair Value Assets | 4,543 | 4,215 |
Estimated Fair Value Liabilities | 3,890 | 3,320 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 6,792 | 6,475 |
Estimated Fair Value Assets | 1,051 | 1,312 |
Estimated Fair Value Liabilities | 774 | 600 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 5,188 | 4,550 |
Estimated Fair Value Assets | 1,018 | 1,257 |
Estimated Fair Value Liabilities | 666 | 535 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Foreign currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,454 | 1,475 |
Estimated Fair Value Assets | 33 | 55 |
Estimated Fair Value Liabilities | 67 | 0 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 150 | 450 |
Estimated Fair Value Assets | 0 | 0 |
Estimated Fair Value Liabilities | 41 | 65 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 54,934 | 54,177 |
Estimated Fair Value Assets | 2,914 | 2,509 |
Estimated Fair Value Liabilities | 3,116 | 2,712 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,154 | 4,156 |
Estimated Fair Value Assets | 0 | 1 |
Estimated Fair Value Liabilities | 359 | 265 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Interest rate forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,901 | 6,115 |
Estimated Fair Value Assets | 56 | 51 |
Estimated Fair Value Liabilities | 880 | 938 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Foreign currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 45,879 | 43,906 |
Estimated Fair Value Assets | 2,858 | 2,457 |
Estimated Fair Value Liabilities | 1,877 | 1,509 |
Derivatives Designated as Hedging Instruments [Member] | Foreign Operations Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,553 | 3,503 |
Estimated Fair Value Assets | 578 | 394 |
Estimated Fair Value Liabilities | 0 | 8 |
Derivatives Designated as Hedging Instruments [Member] | Foreign Operations Hedges [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,553 | 503 |
Estimated Fair Value Assets | 42 | 0 |
Estimated Fair Value Liabilities | 0 | 8 |
Derivatives Designated as Hedging Instruments [Member] | Foreign Operations Hedges [Member] | Currency options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 3,000 | 3,000 |
Estimated Fair Value Assets | 536 | 394 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument, Economic Hedge | Derivative Contract [Domain] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | (476) | (596) |
Not Designated as Hedging Instrument, Economic Hedge | Interest rate |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 8,913 | 9,096 |
Estimated Fair Value Assets | 11 | 13 |
Estimated Fair Value Liabilities | 768 | 663 |
Not Designated as Hedging Instrument, Economic Hedge | Foreign currency exchange rate |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 378 | 716 |
Estimated Fair Value Assets | 0 | 22 |
Estimated Fair Value Liabilities | 2 | 2 |
Not Designated as Hedging Instrument, Economic Hedge | Equity |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,294 | 5,189 |
Estimated Fair Value Assets | 132 | 77 |
Estimated Fair Value Liabilities | 113 | 373 |
Not Designated as Hedging Instrument [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 199,269 | 237,079 |
Estimated Fair Value Assets | 3,669 | 4,522 |
Estimated Fair Value Liabilities | 3,369 | 2,978 |
Derivative, Gain (Loss) on Derivative, Net | (2,414) | (3,234) | $ (3,401)
Not Designated as Hedging Instrument [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 29,238 | 29,801 |
Estimated Fair Value Assets | 1,414 | 1,497 |
Estimated Fair Value Liabilities | 1,263 | 1,102 |
Not Designated as Hedging Instrument [Member] | Interest rate forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 3,128 | 2,383 |
Estimated Fair Value Assets | 135 | 69 |
Estimated Fair Value Liabilities | 77 | 36 |
Not Designated as Hedging Instrument [Member] | Interest rate floors |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 6,169 | 15,321 |
Estimated Fair Value Assets | 38 | 41 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Interest rate caps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 17,998 | 30,016 |
Estimated Fair Value Assets | 133 | 373 |
Estimated Fair Value Liabilities | 1 | 0 |
Not Designated as Hedging Instrument [Member] | Interest rate futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,667 | 1,243 |
Estimated Fair Value Assets | 1 | 1 |
Estimated Fair Value Liabilities | 1 | 5 |
Not Designated as Hedging Instrument [Member] | Interest rate options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 34,939 | 43,926 |
Estimated Fair Value Assets | 210 | 385 |
Estimated Fair Value Liabilities | 217 | 103 |
Not Designated as Hedging Instrument [Member] | Synthetic GICs |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 49,599 | 49,066 |
Estimated Fair Value Assets | 0 | 0 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Foreign currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 10,708 | 11,891 |
Estimated Fair Value Assets | 1,192 | 1,200 |
Estimated Fair Value Liabilities | 190 | 356 |
Not Designated as Hedging Instrument [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 13,471 | 14,128 |
Estimated Fair Value Assets | 47 | 310 |
Estimated Fair Value Liabilities | 1,277 | 806 |
Not Designated as Hedging Instrument [Member] | Currency futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 301 | 314 |
Estimated Fair Value Assets | 1 | 2 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Currency options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 0 | 50 |
Estimated Fair Value Assets | 0 | 0 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Credit default swaps — purchased |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 2,791 | 2,877 |
Estimated Fair Value Assets | 14 | 3 |
Estimated Fair Value Liabilities | 67 | 79 |
Not Designated as Hedging Instrument [Member] | Credit default swaps — written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 11,764 | 12,468 |
Estimated Fair Value Assets | 201 | 233 |
Estimated Fair Value Liabilities | 5 | 5 |
Not Designated as Hedging Instrument [Member] | Equity futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,840 | 2,163 |
Estimated Fair Value Assets | 9 | 8 |
Estimated Fair Value Liabilities | 6 | 11 |
Not Designated as Hedging Instrument [Member] | Equity index options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 12,743 | 19,421 |
Estimated Fair Value Assets | 233 | 399 |
Estimated Fair Value Liabilities | 253 | 255 |
Not Designated as Hedging Instrument [Member] | Equity variance swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 114 | 99 |
Estimated Fair Value Assets | 0 | 0 |
Estimated Fair Value Liabilities | 3 | 2 |
Not Designated as Hedging Instrument [Member] | Equity Total Return Swaps [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,799 | 1,912 |
Estimated Fair Value Assets | 41 | 1 |
Estimated Fair Value Liabilities | 9 | 218 |
Not Designated as Hedging Instrument [Member] | Derivatives hedging MRBs |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 13,585 | 15,001 |
Estimated Fair Value Assets | 143 | 112 |
Estimated Fair Value Liabilities | 883 | 1,038 |
Not Designated as Hedging Instrument [Member] | Longevity Swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,000 | 0 |
Derivative Asset, Not Subject to Master Netting Arrangement | 0 | 0 |
Derivative Liability, Not Subject to Master Netting Arrangement | $ 0 | $ 0 |

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