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Derivatives (Primary Risks) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | $ 290,446 |  | $ 290,446 |  | $ 301,234
Estimated Fair Value Assets | 8,172 |  | 8,172 |  | 8,737
Estimated Fair Value Liabilities | 6,357 |  | 6,357 |  | 6,298
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net | 10 | $ 1 | 4 | $ 28 |
Accumulated Other Comprehensive Income Loss | (457) |  | (457) |  | 166
Cash Flow Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | 0 | 0 | 0 |
Cash Flow Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | 0 | 0 | 0 |
Cash Flow Hedges [Member] | Interest Rate Contract |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | 0 | 0 | 0 |
Not Designated as Hedging Instrument, Economic Hedge | Derivative Contract [Domain] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Gain (Loss) on Derivative, Net |  |  | (395) | (740) |
Derivatives Designated as Hedging Instruments: |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 65,637 |  | 65,637 |  | 64,155
Estimated Fair Value Assets | 4,113 |  | 4,113 |  | 4,215
Estimated Fair Value Liabilities | 3,467 |  | 3,467 |  | 3,320
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 7,202 |  | 7,202 |  | 6,475
Estimated Fair Value Assets | 1,177 |  | 1,177 |  | 1,312
Estimated Fair Value Liabilities | 630 |  | 630 |  | 600
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 5,188 |  | 5,188 |  | 4,550
Estimated Fair Value Assets | 1,134 |  | 1,134 |  | 1,257
Estimated Fair Value Liabilities | 554 |  | 554 |  | 535
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,664 |  | 1,664 |  | 1,475
Estimated Fair Value Assets | 43 |  | 43 |  | 55
Estimated Fair Value Liabilities | 7 |  | 7 |  | 0
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 350 |  | 350 |  | 450
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 69 |  | 69 |  | 65
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 55,230 |  | 55,230 |  | 54,177
Estimated Fair Value Assets | 2,517 |  | 2,517 |  | 2,509
Estimated Fair Value Liabilities | 2,837 |  | 2,837 |  | 2,712
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 4,155 |  | 4,155 |  | 4,156
Estimated Fair Value Assets | 0 |  | 0 |  | 1
Estimated Fair Value Liabilities | 259 |  | 259 |  | 265
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 5,090 |  | 5,090 |  | 6,115
Estimated Fair Value Assets | 59 |  | 59 |  | 51
Estimated Fair Value Liabilities | 923 |  | 923 |  | 938
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 45,985 |  | 45,985 |  | 43,906
Estimated Fair Value Assets | 2,458 |  | 2,458 |  | 2,457
Estimated Fair Value Liabilities | 1,655 |  | 1,655 |  | 1,509
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,205 |  | 3,205 |  | 3,503
Estimated Fair Value Assets | 419 |  | 419 |  | 394
Estimated Fair Value Liabilities | 0 |  | 0 |  | 8
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 205 |  | 205 |  | 503
Estimated Fair Value Assets | 7 |  | 7 |  | 0
Estimated Fair Value Liabilities | 0 |  | 0 |  | 8
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] | Currency options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,000 |  | 3,000 |  | 3,000
Estimated Fair Value Assets | 412 |  | 412 |  | 394
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 224,809 |  | 224,809 |  | 237,079
Estimated Fair Value Assets | 4,059 |  | 4,059 |  | 4,522
Estimated Fair Value Liabilities | 2,890 |  | 2,890 |  | 2,978
Derivative, Gain (Loss) on Derivative, Net | 673 | $ (1,538) | (1,253) | $ (3,198) |
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 29,675 |  | 29,675 |  | 29,801
Estimated Fair Value Assets | 1,654 |  | 1,654 |  | 1,497
Estimated Fair Value Liabilities | 1,062 |  | 1,062 |  | 1,102
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 2,934 |  | 2,934 |  | 2,383
Estimated Fair Value Assets | 130 |  | 130 |  | 69
Estimated Fair Value Liabilities | 76 |  | 76 |  | 36
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate floors |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 9,228 |  | 9,228 |  | 15,321
Estimated Fair Value Assets | 48 |  | 48 |  | 41
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate caps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 29,052 |  | 29,052 |  | 30,016
Estimated Fair Value Assets | 130 |  | 130 |  | 373
Estimated Fair Value Liabilities | 1 |  | 1 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,732 |  | 1,732 |  | 1,243
Estimated Fair Value Assets | 2 |  | 2 |  | 1
Estimated Fair Value Liabilities | 2 |  | 2 |  | 5
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 43,481 |  | 43,481 |  | 43,926
Estimated Fair Value Assets | 269 |  | 269 |  | 385
Estimated Fair Value Liabilities | 119 |  | 119 |  | 103
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Synthetic GICs |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 49,081 |  | 49,081 |  | 49,066
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 10,755 |  | 10,755 |  | 11,891
Estimated Fair Value Assets | 981 |  | 981 |  | 1,200
Estimated Fair Value Liabilities | 231 |  | 231 |  | 356
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 13,511 |  | 13,511 |  | 14,128
Estimated Fair Value Assets | 283 |  | 283 |  | 310
Estimated Fair Value Liabilities | 961 |  | 961 |  | 806
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Currency futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 321 |  | 321 |  | 314
Estimated Fair Value Assets | 2 |  | 2 |  | 2
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Currency options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 0 |  | 0 |  | 50
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Credit default swaps — purchased |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 2,801 |  | 2,801 |  | 2,877
Estimated Fair Value Assets | 4 |  | 4 |  | 3
Estimated Fair Value Liabilities | 74 |  | 74 |  | 79
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Credit default swaps — written |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 12,851 |  | 12,851 |  | 12,468
Estimated Fair Value Assets | 267 |  | 267 |  | 233
Estimated Fair Value Liabilities | 2 |  | 2 |  | 5
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,866 |  | 1,866 |  | 2,163
Estimated Fair Value Assets | 13 |  | 13 |  | 8
Estimated Fair Value Liabilities | 6 |  | 6 |  | 11
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity index options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 14,106 |  | 14,106 |  | 19,421
Estimated Fair Value Assets | 276 |  | 276 |  | 399
Estimated Fair Value Liabilities | 263 |  | 263 |  | 255
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity variance swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 114 |  | 114 |  | 99
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 3 |  | 3 |  | 2
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity total return swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 2,301 |  | 2,301 |  | 1,912
Estimated Fair Value Assets | 0 |  | 0 |  | 1
Estimated Fair Value Liabilities | 90 |  | 90 |  | 218
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Longevity Swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,000 |  | 1,000 |  | 0
Derivative Liability, Not Subject to Master Netting Arrangement | 0 |  | 0 |  | 0
Derivative Asset, Not Subject to Master Netting Arrangement | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Derivatives hedging MRBs |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 14,328 |  | 14,328 |  | 15,001
Estimated Fair Value Assets | 127 |  | 127 |  | 112
Estimated Fair Value Liabilities | 797 |  | 797 |  | 1,038
Not Designated as Hedging Instrument, Economic Hedge | Interest Rate Contract |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 9,092 |  | 9,092 |  | 9,096
Estimated Fair Value Assets | 13 |  | 13 |  | 13
Estimated Fair Value Liabilities | 603 |  | 603 |  | 663
Not Designated as Hedging Instrument, Economic Hedge | Foreign currency exchange rate |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 577 |  | 577 |  | 716
Estimated Fair Value Assets | 20 |  | 20 |  | 22
Estimated Fair Value Liabilities | 1 |  | 1 |  | 2
Not Designated as Hedging Instrument, Economic Hedge | Equity |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 4,659 |  | 4,659 |  | 5,189
Estimated Fair Value Assets | 94 |  | 94 |  | 77
Estimated Fair Value Liabilities | $ 193 |  | $ 193 |  | $ 373

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