| **Investments (Narrative) (Details) - USD ($) $ in Millions**                                                                                       | 3 Months Ended |         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------|----------------|---------|
||
| **Investments [Abstract]**                                                                                                                          |           |    |
| Gains (Losses) on Extinguishment of Debt                                                                                                            | $ 8            |    |
| Reduction of net unrealized gains on investments included in AOCI due to shadow adjustments                                                         | 1,311          | $ 1,111 |
| Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value                                          | 2,446          |    |
| Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis                           | 2,464          |    |
| Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value, unrealized loss position                | 1,069          |    |
| Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis, unrealized loss position | 1,202          |    |
| Derivative, Notional Amount                                                                                                                         | 178            | 179     |
| Derivative Asset, Fair Value, Gross Asset                                                                                                           | 1              |    |
| Derivative Liability, Fair Value, Gross Liability                                                                                                   |           | $ (5)   |
| Future Capital Call Commitments                                                                                                                     | 371            |    |
| Mortgage Loan Commitments                                                                                                                           | 10             |    |
| Commitments To Purchase Or Fund Additional Amounts                                                                                                  | 163            |    |
| Commitments To Sell Various Privately Placed Debt Securities                                                                                        | $ 166          |    |

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Commitments To Purchase Or Fund Additional Amounts
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Commitments To Sell Various Privately Placed Debt Securities
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Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis
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Fixed maturity securities and equity securities in the energy and metals and mining sectors, amortized cost or cost basis, unrealized loss position
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Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value
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Fixed maturity securities and equity securities in the energy and metals and mining sectors, at fair value, unrealized loss position
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Future capital call commitments to limited partnerships for which we would receive an ownership interest.
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Mortgage loan commitments, representing signed loan applications received and accepted.
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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.
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Fair value, before effects of master netting arrangements, of a financial asset or other 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 assets elected not to be offset. Excludes assets not subject to a master netting arrangement.
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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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| - Definition
Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.
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