Investments (Components of Net Investment Gains Losses) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Marketable Securities, Gain (Loss) [Abstract]
Fixed maturity securities AFS - net gains (losses) on sales and disposals	$ 219	$ (14)
Equity securities - net gains (losses) on sales and disposals	8	43
Change In Estimated Fair Value Of Equity Securities	(292)	64
Other net investment gains (losses):
Mortgage loans	(63)	(15)
Real estate and real estate joint ventures	1	5
Other limited partnership interests	4	0
Other (3)	25	(68)
Subtotal - investment portfolio gains (losses)	(313)	5
Change In Estimated Fair Value Of Other Limited Partnership Interests And Real Estate Joint Ventures	1	(15)
Non-investment portfolio gains (losses)	24	25
Subtotal	25	10
Total net investment gains (losses)	(288)	15
Changes In Estimated Fair Value Subsequent To Purchase For Equity Securities	(288)	97
Fixed Maturity Securities
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings		(10)
Current expected credit loss recognized in earnings	(215)
Net investment gains (losses)	4	(24)
Equity Securities
Marketable Securities, Gain (Loss) [Abstract]
Net investment gains (losses)	$ (284)	107
Industrial Domestic Corporate Debt Securities
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings		(8)
RMBS
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings		(2)
Tax credit partnerships
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings		(78)
Other limited partnership interests
Other net investment gains (losses):
Other (3)		$ 46

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Change In Estimated Fair Value Of Other Limited Partnership Interests And Real Estate Joint Ventures.

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Changes In Estimated Fair Value Subsequent To Purchase For Equity Securities Still Held As Of The End Of The Period Included In Net Income Gains (Losses).

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Current expected credit Loss, Debt Securities, Portion Recognized in Earnings

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The net gain or loss incurred on assets and liabilities held by consolidated securitizations entities and all other gains and losses.

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The net gain (loss) resulting from sales and other disposals of other limited partnership interests.

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The difference between the carrying value and the sale price of debt securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale.

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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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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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