| **Investments (Narrative) (Details) - USD ($)**                                             | 3 Months Ended  |              |
|---------------------------------------------------------------------------------------------|-----------------|--------------|
||
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Reduction of net unrealized gains on investments included in AOCI due to shadow adjustments | $ 1,700,000,000 |         | $ 2,198,000,000 |
| Notional value                                                                              | 196,000,000     |         | 182,000,000 |
| Derivative liability, fair value, gross liability                                           | (1,000,000)     |         | $ (7,000,000) |
| Commitments to purchase or fund privately placed debt securities                            | 1,025,000,000   |         |   |
| Commitments to sell various privately placed debt securities                                | 85,000,000      |         |   |
| Common Stock                                                                                |            |         |   |
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Equity securities, FV-NI, gain (loss)                                                       | (45,000,000)    | $ 17,000,000 |   |
| Trading portfolio                                                                           |            |         |   |
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Equity securities, FV-NI, gain (loss)                                                       | (2,000,000)     | 1,000,000    |   |
| Preferred stock                                                                             |            |         |   |
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Equity securities, FV-NI, gain (loss)                                                       | (133,000,000)   | $ 42,000,000 |   |
| Fixed maturity securities                                                                   |            |         |   |
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Interest Receivable                                                                         | 390,000,000     |         |   |
| Mortgage loans                                                                              |            |         |   |
| **Gain (Loss) on Securities [Line Items]**                                                  |            |         |   |
| Interest Receivable                                                                         | 4,000,000       |         |   |
| Debt securities, available-for-sale, allowance for credit loss, period increase (decrease)  | 13,000,000      |         |   |
| Financing receivable, allowance for credit loss, writeoff                                   | $ 0             |         |   |

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.
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Nominal or face amount used to calculate payment on derivative.
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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).
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Amount of increase (decrease) in allowance for credit loss on financing receivable.
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Amount of writeoff of financing receivable, charged against allowance for credit loss.
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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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