|**Income Taxes (Tables)**                                                                  | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|**Income Tax Disclosure [Abstract]**                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Differences Between The 35 Percent Statutory Income Tax Rate And Effective Income Tax Rate | The differences between the35percent statutory income tax rate and our effective income tax rate were as follows:(In millions)Three months ended June 30,Six months ended June 30,2014201320142013Tax at statutory rate$3735.0%$5235.0%$7935.0%$12835.0%Increase (decrease) resulting from:Tax-exempt income from municipal bonds(8)(7.5)(9)(6.1)(16)(7.1)(16)(4.4)Dividend received exclusion(7)(6.5)(6)(4.2)(14)(6.2)(12)(3.3)Other10.511.020.910.4Provision for income taxes$2321.5%$3825.7%$5122.6%$10127.7%
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|(In millions)                                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|Tax at statutory rate                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Increase (decrease) resulting from:                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Tax-exempt income from municipal bonds                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Dividend received exclusion                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Other                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Provision for income taxes                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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                    duration X- DefinitionTabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.+ ReferencesReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319+ Details**Name:**
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