Investments (Investment Related Gains (Losses) Net) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Investment Gains And Losses [Abstract]
Gain on investment activity	$ (53)	$ (46)	$ (220)	$ (73)
Available-for-sale Securities, Realized Losses, Excluding Other than Temporary Impairments	(30)	(46)	(43)	(54)
Gain (Loss) on Sale of Equity Investments	20	8	23	(15)
Other impairment losses and change in mortgage loan provision	3	(22)	21	(35)
Derivatives and other, net	29	87	47	(156)
Total investment related gains (losses), net	112	81	414	(204)
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net	5	0	3	(34)
Change in Fair Value Limited Partnership Investments and Other Net	$ 32	$ 8	$ 143	$ 17

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.

+ References

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Other impairment losses and change in mortgage loan provision.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

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Amount of loss realized on the sale of debt or equity securities classified as available-for-sale. Excludes other than temporary impairments (OTTI).

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No definition available.

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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
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

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The difference between the carrying value and the sale price of equity securities, not separately or otherwise categorized as trading or available-for-sale. This element includes investments in which the entity holds a small ownership stake (generally, less than 20% of the shares outstanding) and cannot exert significant influence.

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Amount of realized gain (loss) on investment.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.3(a))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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