Federal Income Taxes (Reconciliation Of The Effective Tax Rate Differences) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of effective tax rate differences [Abstract]
Tax rate times pre-tax income	$ 384	$ 256	$ 504
Effect of:
Tax-preferred investment income	(87)	(280)	(196)
Tax credits	(39)	(29)	(28)
Change in uncertain tax positions	1	(17)	(11)
Excess tax benefits from share-based compensation	(3)	(8)	(4)
Goodwill impairment		316
Deferred tax impact from the Tax Cuts and Jobs Act	3	(1,526)
Other items	(2)	1	2
Federal income tax expense (benefit)	$ 257	$ (1,287)	$ 267
Effective tax rate	14.00%	(176.00%)	19.00%

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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