Federal Income Taxes (Reconciliation Of The Effective Tax Rate Differences) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of effective tax rate differences [Abstract]
Income (loss) before taxes		$ 919	$ 1,885	$ 1,130
Federal statutory rate		21.00%	21.00%	35.00%
Federal income tax expense (benefit) at federal statutory rate		$ 193	$ 396	$ 396
Effect of:
Tax-preferred investment income	[1]	(99)	(87)	(280)
Tax credits		(40)	(39)	(29)
Excess tax benefits from share-based compensation		(9)	(5)	(12)
Goodwill impairment				316
Tax impact associated with the Tax Cuts and Jobs Act	[2]	(17)	(19)	(1,322)
Other items		5	(2)	(18)
Federal income tax expense (benefit)		$ 33	$ 244	$ (949)
Effective tax rate		4.00%	13.00%	(84.00%)
Variable Annuity [Member]
Effect of:
Tax impact associated with the Tax Cuts and Jobs Act			$ (27)

[1] Relates primarily to separate account dividends eligible for the dividends-received deduction. As a result of the Tax Cuts and Jobs Act (the “Tax Act”), the recorded tax benefit for the separate account dividends-received deduction was substantially less in 2019 and 2018 as compared to 2017.

[2] As a result of the enactment of the Tax Act in 2017, we remeasured our existing deferred tax balances at the prevailing corporate federal income tax rate of 21% and recognized a $1.3 billion tax benefit. In 2018, we recognized a $27 million net tax benefit from the impact of the reduced federal statutory rate under the Tax Act on our adoption of an Internal Revenue Service pronouncement related to variable annuity contracts. In 2019, we recognized a $17 million net tax benefit from the impact of the reduced corporate tax rate under the Tax Act on our election to revalue policyholder tax reserves.