Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Investment Gains And Losses [Abstract]
Gain on investment activity	$ (34)	$ (53)	$ (45)	$ (220)
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(94)	(30)	(130)	(43)
Gain (Loss) on Sale of Equity Investments	(15)	20	(23)	23
Other impairment losses and change in mortgage loan provision	(1)	3	(3)	21
Derivatives and other, net	(182)	29	(287)	47
Total investment related gains (losses), net	(254)	112	(380)	414
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	(15)	5	(27)	3
Change in Fair Value Limited Partnership Investments and Other Net	$ 19	$ 32	$ 45	$ 143

Change in Fair Value Limited Partnership Investments and Other Net

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Net realized gains or losses on investments during the period related to the change in value of embedded derivatives and other realized gains and losses not otherwise categorized.

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Other impairment losses and change in mortgage loan provision.

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Amount of increase (decrease) in allowance for credit loss of 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 326
-SubTopic 30
-Section 50
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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 unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain (loss) on investment.

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