Federal Income Taxes (Reconciliation Of The Effective Tax Rate Differences) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of effective tax rate differences [Abstract]
Income (loss) before taxes	$ 1,922	$ 535	$ 577
Federal statutory rate	21.00%	21.00%	21.00%
Federal income tax expense (benefit) at federal statutory rate	$ 404	$ 112	$ 121
Effect of:
Tax-preferred investment income	(88)	(98)	(99)
Tax credits	(26)	(39)	(40)
Excess tax benefits from stock-based compensation		2	(6)
Tax impact		(37)	(16)
Other items	3	4	3
Federal income tax expense (benefit)	$ 293	$ (56)	$ (37)
Effective tax rate	15.00%	(10.00%)	(6.00%)
Net operating loss carryforwards	$ 1,400
Tax Year 2020 [Member]
Effect of:
Net operating loss carryforwards		$ 37

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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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