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Derivatives (Primary Risks) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | $ 301,234 | $ 328,116 |
Estimated Fair Value Assets | 8,737 | 11,411 |
Estimated Fair Value Liabilities | 6,298 | 6,975 |
Derivatives Designated as Hedging Instruments [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 64,155 | 63,923 |
Estimated Fair Value Assets | 4,215 | 5,244 |
Estimated Fair Value Liabilities | 3,320 | 3,909 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 6,475 | 6,081 |
Estimated Fair Value Assets | 1,312 | 1,445 |
Estimated Fair Value Liabilities | 600 | 556 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,550 | 4,143 |
Estimated Fair Value Assets | 1,257 | 1,353 |
Estimated Fair Value Liabilities | 535 | 467 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Foreign currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,475 | 602 |
Estimated Fair Value Assets | 55 | 82 |
Estimated Fair Value Liabilities | 0 | 0 |
Derivatives Designated as Hedging Instruments [Member] | Fair Value Hedges [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 450 | 1,336 |
Estimated Fair Value Assets | 0 | 10 |
Estimated Fair Value Liabilities | 65 | 89 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 54,177 | 54,162 |
Estimated Fair Value Assets | 2,509 | 3,563 |
Estimated Fair Value Liabilities | 2,712 | 3,315 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 4,156 | 4,107 |
Estimated Fair Value Assets | 1 | 8 |
Estimated Fair Value Liabilities | 265 | 262 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Interest rate forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 6,115 | 7,447 |
Estimated Fair Value Assets | 51 | 1 |
Estimated Fair Value Liabilities | 938 | 1,354 |
Derivatives Designated as Hedging Instruments [Member] | Cash Flow Hedges [Member] | Foreign currency swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 43,906 | 42,608 |
Estimated Fair Value Assets | 2,457 | 3,554 |
Estimated Fair Value Liabilities | 1,509 | 1,699 |
Derivatives Designated as Hedging Instruments [Member] | Foreign Operations Hedges [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 3,503 | 3,680 |
Estimated Fair Value Assets | 394 | 236 |
Estimated Fair Value Liabilities | 8 | 38 |
Derivatives Designated as Hedging Instruments [Member] | Foreign Operations Hedges [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 503 | 680 |
Estimated Fair Value Assets | 0 | 0 |
Estimated Fair Value Liabilities | 8 | 38 |
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 | 394 | 236 |
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 | (596) | (640) |
Not Designated as Hedging Instrument, Economic Hedge | Interest rate |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 9,096 | 9,098 |
Estimated Fair Value Assets | 13 | 41 |
Estimated Fair Value Liabilities | 663 | 764 |
Not Designated as Hedging Instrument, Economic Hedge | Foreign currency exchange rate |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 716 | 887 |
Estimated Fair Value Assets | 22 | 26 |
Estimated Fair Value Liabilities | 2 | 2 |
Not Designated as Hedging Instrument, Economic Hedge | Equity |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 5,189 | 8,829 |
Estimated Fair Value Assets | 77 | 233 |
Estimated Fair Value Liabilities | 373 | 381 |
Not Designated as Hedging Instrument [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 237,079 | 264,193 |
Estimated Fair Value Assets | 4,522 | 6,167 |
Estimated Fair Value Liabilities | 2,978 | 3,066 |
Derivative, Gain (Loss) on Derivative, Net | (3,234) | (3,401) | $ (4,305)
Not Designated as Hedging Instrument [Member] | Interest rate swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 29,801 | 31,661 |
Estimated Fair Value Assets | 1,497 | 1,660 |
Estimated Fair Value Liabilities | 1,102 | 1,354 |
Not Designated as Hedging Instrument [Member] | Interest rate forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 2,383 | 381 |
Estimated Fair Value Assets | 69 | 0 |
Estimated Fair Value Liabilities | 36 | 32 |
Not Designated as Hedging Instrument [Member] | Interest rate floors |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 15,321 | 25,270 |
Estimated Fair Value Assets | 41 | 125 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Interest rate caps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 30,016 | 48,290 |
Estimated Fair Value Assets | 373 | 950 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Interest rate futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,243 | 1,453 |
Estimated Fair Value Assets | 1 | 2 |
Estimated Fair Value Liabilities | 5 | 1 |
Not Designated as Hedging Instrument [Member] | Interest rate options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 43,926 | 44,391 |
Estimated Fair Value Assets | 385 | 473 |
Estimated Fair Value Liabilities | 103 | 88 |
Not Designated as Hedging Instrument [Member] | Synthetic GICs |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 49,066 | 46,316 |
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 | 11,891 | 12,815 |
Estimated Fair Value Assets | 1,200 | 1,454 |
Estimated Fair Value Liabilities | 356 | 383 |
Not Designated as Hedging Instrument [Member] | Foreign currency forwards |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 14,128 | 16,195 |
Estimated Fair Value Assets | 310 | 544 |
Estimated Fair Value Liabilities | 806 | 661 |
Not Designated as Hedging Instrument [Member] | Currency futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 314 | 333 |
Estimated Fair Value Assets | 2 | 8 |
Estimated Fair Value Liabilities | 0 | 0 |
Not Designated as Hedging Instrument [Member] | Currency options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 50 | 0 |
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 | 2,877 | 2,925 |
Estimated Fair Value Assets | 3 | 18 |
Estimated Fair Value Liabilities | 79 | 79 |
Not Designated as Hedging Instrument [Member] | Credit default swaps — written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 12,468 | 11,512 |
Estimated Fair Value Assets | 233 | 133 |
Estimated Fair Value Liabilities | 5 | 28 |
Not Designated as Hedging Instrument [Member] | Equity futures |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 2,163 | 2,988 |
Estimated Fair Value Assets | 8 | 8 |
Estimated Fair Value Liabilities | 11 | 4 |
Not Designated as Hedging Instrument [Member] | Equity index options |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 19,421 | 16,701 |
Estimated Fair Value Assets | 399 | 765 |
Estimated Fair Value Liabilities | 255 | 323 |
Not Designated as Hedging Instrument [Member] | Equity variance swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 99 | 163 |
Estimated Fair Value Assets | 0 | 4 |
Estimated Fair Value Liabilities | 2 | 1 |
Not Designated as Hedging Instrument [Member] | Equity Total Return Swaps [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 1,912 | 2,799 |
Estimated Fair Value Assets | 1 | 23 |
Estimated Fair Value Liabilities | 218 | 112 |
Not Designated as Hedging Instrument [Member] | Derivatives hedging MRBs |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | 15,001 | 18,814 |
Estimated Fair Value Assets | 112 | 300 |
Estimated Fair Value Liabilities | $ 1,038 | $ 1,147 |

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