Investments (Components of Net Investment Gains Losses) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Marketable Securities, Gain (Loss) [Abstract]
Fixed maturity securities AFS	$ 129	$ 113	$ 67	$ 267
Equity securities (1)	(33)	2	97	(210)
Other net investment gains (losses):
Mortgage loans	43	(5)	101	(148)
Real estate and real estate joint ventures	66	1	482	4
Other limited partnership interests	(4)	(4)	(17)	1
Other (2), (3)	19	34	61	159
Subtotal - investment portfolio gains (losses)	221	142	796	71
Change In Estimated Fair Value Of Other Limited Partnership Interests And Real Estate Joint Ventures	9	3	23	(9)
Non-investment portfolio gains (losses) (4)	(314)	(165)	836	(139)
Subtotal	(305)	(162)	859	(148)
Total net investment gains (losses)	(84)	(20)	1,655	(77)
Gain (Loss) on Termination of Lease				81
Cash Flow Hedging [Member]
Other net investment gains (losses):
Total net investment gains (losses)	3	52	43	139
FVO Securities (1)
Marketable Securities, Gain (Loss) [Abstract]
Net investment gains (losses)	1	1	5	(2)
Equity Securities
Other net investment gains (losses):
Equity Securities, FV-NI, Unrealized Gain (Loss)	(16)	(2)	86	(198)
Foreign Currency Gain (Loss) [Member] \| Reclassification out of Accumulated Other Comprehensive Income \| Cash Flow Hedging [Member]
Other net investment gains (losses):
Total net investment gains (losses)	$ 6	$ 10	$ 54	$ 65

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

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