Investments (Evaluation of Available-For-Sale Securities for OTTI and Evaluating Temporarily Impaired AFS Securities - Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-sale, Unrealized Loss Position, Accumulated Loss	$ 1,300
Investment Grade
Debt Securities, Available-for-sale [Line Items]
Equal to or Greater than 12 Months Gross Unrealized Loss	185	$ 530
Below Investment Grade
Debt Securities, Available-for-sale [Line Items]
Equal to or Greater than 12 Months Gross Unrealized Loss	54	153
Fixed maturity securities without an allowance for credit loss
Debt Securities, Available-for-sale [Line Items]
Change in Gross Unrealized Temporary Loss	334
Fixed maturity securities AFS
Debt Securities, Available-for-sale [Line Items]
Equal to or Greater than 12 Months Gross Unrealized Loss	$ 239	$ 683
Twelve Months Or Greater
Debt Securities, Available-for-sale [Line Items]
Percentage of gross unrealized loss	19.00%
Twelve Months Or Greater \| Investment Grade
Debt Securities, Available-for-sale [Line Items]
Percentage of gross unrealized loss	77.00%
Number of Securities	350
Twelve Months Or Greater \| Below Investment Grade
Debt Securities, Available-for-sale [Line Items]
Percentage of gross unrealized loss	23.00%
Number of Securities	61

The percentage of gross unrealized loss.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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- Definition

Amount, before tax and after adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

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- Definition

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.

+ References

No definition available.

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