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Derivatives (Primary Risks) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | $ 288,778 |  | $ 288,778 |  | $ 301,234
Estimated Fair Value Assets | 8,241 |  | 8,241 |  | 8,737
Estimated Fair Value Liabilities | 7,347 |  | 7,347 |  | $ 6,298
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net | 4 | $ 26 | $ (6) | $ 27 |
Maximum Length of Time Hedged in Cash Flow Hedge |  |  | 5 years |  | 5 years
Accumulated Other Comprehensive Income Loss | 25 |  | $ 25 |  | $ 166
Cash Flow Hedges [Member] |  |  |  |  |
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 |  |  | (385) | (501) |
Derivatives Designated as Hedging Instruments: |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 65,275 |  | 65,275 |  | 64,155
Estimated Fair Value Assets | 4,389 |  | 4,389 |  | 4,215
Estimated Fair Value Liabilities | 3,823 |  | 3,823 |  | 3,320
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 6,661 |  | 6,661 |  | 6,475
Estimated Fair Value Assets | 1,131 |  | 1,131 |  | 1,312
Estimated Fair Value Liabilities | 743 |  | 743 |  | 600
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 4,978 |  | 4,978 |  | 4,550
Estimated Fair Value Assets | 1,094 |  | 1,094 |  | 1,257
Estimated Fair Value Liabilities | 644 |  | 644 |  | 535
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,333 |  | 1,333 |  | 1,475
Estimated Fair Value Assets | 37 |  | 37 |  | 55
Estimated Fair Value Liabilities | 12 |  | 12 |  | 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 | 87 |  | 87 |  | 65
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 55,208 |  | 55,208 |  | 54,177
Estimated Fair Value Assets | 2,666 |  | 2,666 |  | 2,509
Estimated Fair Value Liabilities | 3,080 |  | 3,080 |  | 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 | 353 |  | 353 |  | 265
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 5,590 |  | 5,590 |  | 6,115
Estimated Fair Value Assets | 33 |  | 33 |  | 51
Estimated Fair Value Liabilities | 1,008 |  | 1,008 |  | 938
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 45,463 |  | 45,463 |  | 43,906
Estimated Fair Value Assets | 2,633 |  | 2,633 |  | 2,457
Estimated Fair Value Liabilities | 1,719 |  | 1,719 |  | 1,509
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,406 |  | 3,406 |  | 3,503
Estimated Fair Value Assets | 592 |  | 592 |  | 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 | 406 |  | 406 |  | 503
Estimated Fair Value Assets | 51 |  | 51 |  | 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 | 541 |  | 541 |  | 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 | 223,503 |  | 223,503 |  | 237,079
Estimated Fair Value Assets | 3,852 |  | 3,852 |  | 4,522
Estimated Fair Value Liabilities | 3,524 |  | 3,524 |  | 2,978
Derivative, Gain (Loss) on Derivative, Net | (715) | $ (1,257) | (1,926) | $ (1,660) |
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 29,726 |  | 29,726 |  | 29,801
Estimated Fair Value Assets | 1,459 |  | 1,459 |  | 1,497
Estimated Fair Value Liabilities | 1,276 |  | 1,276 |  | 1,102
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 2,816 |  | 2,816 |  | 2,383
Estimated Fair Value Assets | 42 |  | 42 |  | 69
Estimated Fair Value Liabilities | 82 |  | 82 |  | 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 | 34 |  | 34 |  | 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 | 27,152 |  | 27,152 |  | 30,016
Estimated Fair Value Assets | 245 |  | 245 |  | 373
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,853 |  | 1,853 |  | 1,243
Estimated Fair Value Assets | 4 |  | 4 |  | 1
Estimated Fair Value Liabilities | 3 |  | 3 |  | 5
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 42,377 |  | 42,377 |  | 43,926
Estimated Fair Value Assets | 232 |  | 232 |  | 385
Estimated Fair Value Liabilities | 153 |  | 153 |  | 103
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Synthetic GICs |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 48,982 |  | 48,982 |  | 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 | 10,716 |  | 10,716 |  | 11,891
Estimated Fair Value Assets | 1,210 |  | 1,210 |  | 1,200
Estimated Fair Value Liabilities | 140 |  | 140 |  | 356
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 13,657 |  | 13,657 |  | 14,128
Estimated Fair Value Assets | 29 |  | 29 |  | 310
Estimated Fair Value Liabilities | 1,398 |  | 1,398 |  | 806
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Currency futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 292 |  | 292 |  | 314
Estimated Fair Value Assets | 0 |  | 0 |  | 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 | 320 |  | 320 |  | 50
Estimated Fair Value Assets | 35 |  | 35 |  | 0
Estimated Fair Value Liabilities | 35 |  | 35 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Credit default swaps — purchased |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 2,812 |  | 2,812 |  | 2,877
Estimated Fair Value Assets | 7 |  | 7 |  | 3
Estimated Fair Value Liabilities | 72 |  | 72 |  | 79
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Credit default swaps — written |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 13,952 |  | 13,952 |  | 12,468
Estimated Fair Value Assets | 247 |  | 247 |  | 233
Estimated Fair Value Liabilities | 5 |  | 5 |  | 5
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,790 |  | 1,790 |  | 2,163
Estimated Fair Value Assets | 10 |  | 10 |  | 8
Estimated Fair Value Liabilities | 7 |  | 7 |  | 11
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity index options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 14,714 |  | 14,714 |  | 19,421
Estimated Fair Value Assets | 297 |  | 297 |  | 399
Estimated Fair Value Liabilities | 250 |  | 250 |  | 255
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity variance swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 96 |  | 96 |  | 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 | 2,020 |  | 2,020 |  | 1,912
Estimated Fair Value Assets | 1 |  | 1 |  | 1
Estimated Fair Value Liabilities | 100 |  | 100 |  | 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 | 14,145 |  | 14,145 |  | 15,001
Estimated Fair Value Assets | 136 |  | 136 |  | 112
Estimated Fair Value Liabilities | 988 |  | 988 |  | 1,038
Not Designated as Hedging Instrument, Economic Hedge | Interest Rate Contract |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 9,107 |  | 9,107 |  | 9,096
Estimated Fair Value Assets | 24 |  | 24 |  | 13
Estimated Fair Value Liabilities | 762 |  | 762 |  | 663
Not Designated as Hedging Instrument, Economic Hedge | Foreign currency exchange rate |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 505 |  | 505 |  | 716
Estimated Fair Value Assets | 1 |  | 1 |  | 22
Estimated Fair Value Liabilities | 20 |  | 20 |  | 2
Not Designated as Hedging Instrument, Economic Hedge | Equity |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 4,533 |  | 4,533 |  | 5,189
Estimated Fair Value Assets | 111 |  | 111 |  | 77
Estimated Fair Value Liabilities | $ 206 |  | $ 206 |  | $ 373

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