Investments (Net realized investment gains (losses)) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fixed maturity securities:
Gross gains	$ 45	$ 51	$ 71	$ 109
Gross losses	(60)	(20)	(88)	(40)
Net investment gains (losses) on fixed maturity securities	(15)	31	(17)	69
Equity securities	(71)	17	(109)	19
Derivatives	26	(12)	55	5
Short term investments and other	1	2	1	2
Net investment gains (losses)	$ (59)	$ 38	$ (70)	$ 95

Investments And Derivatives, Realized Gain (Loss)

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Realized Gain (Loss) On Short Term Investments

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
-Paragraph 9
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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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-Publisher FASB
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-Publisher FASB
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- Definition

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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