Investments (Components of Net Investment Gains Losses) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Marketable Securities, Gain (Loss) [Abstract]
Fixed maturity securities AFS — net gains (losses) on sales and disposals	$ (14)	$ (95)
Equity securities — net gains (losses) on sales and disposals	43	102
Change In Estimated Fair Value Of Equity Securities	64	(133)
Other net investment gains (losses):
Mortgage loans	(15)	(21)
Real estate and real estate joint ventures	5	25
Other (2)	(68)	(130)
Subtotal	5	(252)
Change In Estimated Fair Value Of Other Limited Partnership Interests And Real Estate Joint Ventures	(15)	(5)
Non-investment portfolio gains (losses) (3)	25	(76)
Gains Losses On Assets And Liabilities Held By Consolidated Securitizations Entities Under Fair Value Option And All Other Gains Losses	10	(81)
Total net investment gains (losses)	15	(333)
Changes In Estimated Fair Value Subsequent To Purchase For Equity Securities	97	(37)
Industrial Domestic Corporate Debt Securities
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings	(8)	0
U.S. corporate and foreign corporate securities
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings	(8)	0
RMBS
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings	(2)	0
Fixed Maturity Securities
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings	(10)	0
Net investment gains (losses)	(24)	(95)
Equity Securities
Marketable Securities, Gain (Loss) [Abstract]
Net investment gains (losses)	107	(31)
Tax credit partnerships
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings	(78)
Lease Agreements
Marketable Securities, Gain (Loss) [Abstract]
Total OTTI losses recognized in earnings		(105)
Brighthouse Financial, Inc \| FVO Common Stock
Other net investment gains (losses):
Non-investment portfolio gains (losses) (3)		$ 168
Other limited partnership interests
Other net investment gains (losses):
Other (2)	$ 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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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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This item represents the subtotal of gains (losses)on the investment portfolio.

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Amount of realized and unrealized gain (loss) on investment.

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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 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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