Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fixed maturity securities:
Gross gains	$ 186	$ 220	$ 125
Gross losses	(90)	(220)	(131)
Net investment gains (losses) on fixed maturity securities	96	0	(6)
Equity securities	4	(3)	66
Derivatives	6	(10)	(11)
Mortgage loans	10	(21)	0
Short term investments and other	4	(20)	(20)
Net investment gains (losses)	$ 120	$ (54)	$ 29

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).

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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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