| **Segment Information**          | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Segment Reporting [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Segment Information              | Segment InformationWe operate primarily in two industries, property casualty insurance and life insurance. We regularly review our reporting segments to make decisions about allocating resources and assessing performance. Our reporting segments are:•Commercial lines insurance•Personal lines insurance•Excess and surplus lines insurance•Life insurance•InvestmentsWe report as Other the noninvestment operations of the parent company and its noninsurer subsidiary, CFC Investment Company. See our 2014 Annual Report on Form 10-K, Item 8, Note 18, Segment Information, Page 157, for a description of revenue, income or loss before income taxes and identifiable assets for each of the five segments.Segment information is summarized in the following table: (Dollars in millions) Three months ended March 31,  2015 2014Revenues:    Commercial lines insurance    Commercial casualty $244 $224Commercial property 196 171Commercial auto 136 126Workers' compensation 93 92Other commercial  64 79Commercial lines insurance premiums 733 692Fee revenues 1 1Total commercial lines insurance 734 693     Personal lines insurance    Personal auto 123 116Homeowner 114 109Other personal 31 29Personal lines insurance premiums 268 254Fee revenues 1 —      Total personal lines insurance 269 254     Excess and surplus lines insurance 40 33     Life insurance premiums 53 48Separate account investment management fees 1 2      Total life insurance 54 50     Investments        Investment income, net of expenses 139 135    Realized investment gains, net 47 22        Total investment revenue 186 157     Other 2 2Total revenues $1,285 $1,189     Income (loss) before income taxes:    Insurance underwriting results    Commercial lines insurance $26 $2Personal lines insurance (3) (7)Excess and surplus lines insurance 4 4Life insurance (3) —Investments 165 136Other (15) (16)Total income before income taxes $174 $119Identifiable assets: March 31, 2015 December 31, 2014Property casualty insurance $2,711 $2,656Life insurance 1,306 1,316Investments 14,544 14,441Other 336 340Total $18,897 $18,753      |

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| - Definition
The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.
+ References
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