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Derivatives (Primary Risks) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | $ 321,088 |  | $ 321,088 |  | $ 308,215
Estimated Fair Value Assets | 11,583 |  | 11,583 |  | 10,466
Estimated Fair Value Liabilities | 6,855 |  | 6,855 |  | $ 3,852
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net | 4 | $ 1 | $ 2 | $ (1) |
Maximum Length of Time Hedged in Cash Flow Hedge |  |  | 7 years |  | 7 years
Accumulated Other Comprehensive Income Loss | 2,300 |  | $ 2,300 |  | $ 2,100
Derivatives Designated as Hedging Instruments: |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 64,324 |  | 64,324 |  | 61,088
Estimated Fair Value Assets | 5,281 |  | 5,281 |  | 4,009
Estimated Fair Value Liabilities | 3,363 |  | 3,363 |  | 1,764
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 6,602 |  | 6,602 |  | 5,987
Estimated Fair Value Assets | 1,764 |  | 1,764 |  | 2,175
Estimated Fair Value Liabilities | 467 |  | 467 |  | 87
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 4,331 |  | 4,331 |  | 3,550
Estimated Fair Value Assets | 1,683 |  | 1,683 |  | 2,164
Estimated Fair Value Liabilities | 313 |  | 313 |  | 6
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 735 |  | 735 |  | 801
Estimated Fair Value Assets | 81 |  | 81 |  | 11
Estimated Fair Value Liabilities | 0 |  | 0 |  | 23
Derivatives Designated as Hedging Instruments: | Fair Value Hedges [Member] | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,536 |  | 1,536 |  | 1,636
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 154 |  | 154 |  | 58
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 54,473 |  | 54,473 |  | 52,101
Estimated Fair Value Assets | 3,173 |  | 3,173 |  | 1,695
Estimated Fair Value Liabilities | 2,896 |  | 2,896 |  | 1,677
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,778 |  | 3,778 |  | 4,117
Estimated Fair Value Assets | 14 |  | 14 |  | 6
Estimated Fair Value Liabilities | 0 |  | 0 |  | 1
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 8,042 |  | 8,042 |  | 6,889
Estimated Fair Value Assets | 0 |  | 0 |  | 89
Estimated Fair Value Liabilities | 958 |  | 958 |  | 119
Derivatives Designated as Hedging Instruments: | Cash Flow Hedges [Member] | Foreign currency swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 42,653 |  | 42,653 |  | 41,095
Estimated Fair Value Assets | 3,159 |  | 3,159 |  | 1,600
Estimated Fair Value Liabilities | 1,938 |  | 1,938 |  | 1,557
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,249 |  | 3,249 |  | 3,000
Estimated Fair Value Assets | 344 |  | 344 |  | 139
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Designated as Hedging Instruments: | Foreign Operations Hedges [Member] | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 249 |  | 249 |  | 0
Estimated Fair Value Assets | 25 |  | 25 |  | 0
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
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 | 319 |  | 319 |  | 139
Estimated Fair Value Liabilities | 0 |  | 0 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 256,764 |  | 256,764 |  | 247,127
Estimated Fair Value Assets | 6,302 |  | 6,302 |  | 6,457
Estimated Fair Value Liabilities | 3,492 |  | 3,492 |  | 2,088
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 33,956 |  | 33,956 |  | 38,860
Estimated Fair Value Assets | 2,006 |  | 2,006 |  | 3,644
Estimated Fair Value Liabilities | 887 |  | 887 |  | 115
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 450 |  | 450 |  | 374
Estimated Fair Value Assets | 0 |  | 0 |  | 0
Estimated Fair Value Liabilities | 102 |  | 102 |  | 26
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate floors |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 8,351 |  | 8,351 |  | 7,701
Estimated Fair Value Assets | 35 |  | 35 |  | 145
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 | 66,410 |  | 66,410 |  | 65,559
Estimated Fair Value Assets | 739 |  | 739 |  | 124
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 | 1,106 |  | 1,106 |  | 1,615
Estimated Fair Value Assets | 1 |  | 1 |  | 4
Estimated Fair Value Liabilities | 7 |  | 7 |  | 0
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Interest rate options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 20,304 |  | 20,304 |  | 11,754
Estimated Fair Value Assets | 553 |  | 553 |  | 493
Estimated Fair Value Liabilities | 43 |  | 43 |  | 10
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity total return swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 1,048 |  | 1,048 |  | 1,048
Estimated Fair Value Assets | 0 |  | 0 |  | 9
Estimated Fair Value Liabilities | 109 |  | 109 |  | 4
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Synthetic GICs |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 44,841 |  | 44,841 |  | 40,121
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 | 13,392 |  | 13,392 |  | 12,787
Estimated Fair Value Assets | 1,426 |  | 1,426 |  | 768
Estimated Fair Value Liabilities | 466 |  | 466 |  | 614
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Foreign currency forwards |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 18,043 |  | 18,043 |  | 16,230
Estimated Fair Value Assets | 150 |  | 150 |  | 36
Estimated Fair Value Liabilities | 1,330 |  | 1,330 |  | 666
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Currency futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 727 |  | 727 |  | 839
Estimated Fair Value Assets | 3 |  | 3 |  | 0
Estimated Fair Value Liabilities | 0 |  | 0 |  | 2
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Currency options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 0 |  | 0 |  | 900
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 | 2,993 |  | 2,993 |  | 3,042
Estimated Fair Value Assets | 28 |  | 28 |  | 13
Estimated Fair Value Liabilities | 84 |  | 84 |  | 113
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Credit default swaps — written |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 11,786 |  | 11,786 |  | 8,626
Estimated Fair Value Assets | 35 |  | 35 |  | 177
Estimated Fair Value Liabilities | 84 |  | 84 |  | 12
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity futures |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,592 |  | 3,592 |  | 4,204
Estimated Fair Value Assets | 38 |  | 38 |  | 12
Estimated Fair Value Liabilities | 8 |  | 8 |  | 5
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity index options |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 26,013 |  | 26,013 |  | 29,743
Estimated Fair Value Assets | 1,065 |  | 1,065 |  | 1,004
Estimated Fair Value Liabilities | 360 |  | 360 |  | 458
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity variance swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 692 |  | 692 |  | 699
Estimated Fair Value Assets | 17 |  | 17 |  | 17
Estimated Fair Value Liabilities | 12 |  | 12 |  | 13
Derivatives Not Designated or Not Qualifying as Hedging Instruments: | Equity total return swaps |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |
Derivative, Notional Amount | 3,060 |  | 3,060 |  | 3,025
Estimated Fair Value Assets | 206 |  | 206 |  | 11
Estimated Fair Value Liabilities | $ 0 |  | $ 0 |  | $ 50

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