Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fixed maturity securities:
Gross gains	$ 102	$ 28	$ 131	$ 64
Gross losses	(85)	(31)	(189)	(73)
Net investment gains (losses) on fixed maturity securities	17	(3)	(58)	(9)
Equity securities	63	11	(70)	53
Derivatives	(10)	(6)	(5)	(11)
Mortgage loans	0	0	(13)	0
Short term investments and other	(1)	(20)	(1)	(20)
Net investment gains (losses)	$ 69	$ (18)	$ (147)	$ 13

Investments and Derivatives, Realized Gain (Loss)

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Realized Gain (Loss) on Short Term Investments

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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