Income Taxes (Differences Between The 35 Percent Statutory Income Tax Rate And Effective Income Tax Rate) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Tax at statutory rate:	$ 252	$ 250	$ 198
Tax at statutory rate (percentage):	35.00%	35.00%	35.00%
Increase (decrease) resulting from:
Tax-exempt income from municipal bonds	(33)	(32)	(33)
Dividend received exclusion	(29)	(26)	(24)
Other	6	5	4
Total provision for income taxes	$ 196us-gaap_IncomeTaxExpenseBenefit	$ 197us-gaap_IncomeTaxExpenseBenefit	$ 145us-gaap_IncomeTaxExpenseBenefit
Tax at statutory rate:
Tax-exempt income from municipal bonds (percentage)	(4.60%)	(4.50%)	(5.90%)
Dividend received exclusion (percentage)	(4.00%)	(3.60%)	(4.20%)
Other (percentage)	0.80%	0.70%	0.70%
Effective tax, percentage	27.20%	27.60%	25.60%

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for dividend.

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

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