| **Segment Information**          | 6 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 June 30, Six months ended June 30,  2015 2014 2015 2014Revenues:        Commercial lines insurance        Commercial casualty $252 $234 $496 $458Commercial property 203 180 399 351Commercial auto 139 132 275 258Workers' compensation 90 95 183 187Other commercial  61 73 125 152Commercial lines insurance premiums 745 714 1,478 1,406Fee revenues 1 1 2 2Total commercial lines insurance 746 715 1,480 1,408         Personal lines insurance        Personal auto 125 117 248 233Homeowner 114 111 228 220Other personal 33 30 64 59Personal lines insurance premiums 272 258 540 512Fee revenues — 1 1 1Total personal lines insurance 272 259 541 513         Excess and surplus lines insurance 42 34 82 67Fee revenues 1 — 1 —Total excess and surplus lines insurance 43 34 83 67         Life insurance premiums 52 53 105 101Separate account investment management fees 1 1 2 3Total life insurance 53 54 107 104         Investments            Investment income, net of expenses 140 136 279 271    Realized investment gains, net 60 14 107 36Total investment revenue 200 150 386 307         Other 2 2 4 4Total revenues $1,316 $1,214 $2,601 $2,403         Income (loss) before income taxes:        Insurance underwriting results        Commercial lines insurance $97 $28 $123 $30Personal lines insurance (25) (40) (28) (47)Excess and surplus lines insurance 11 5 15 9Life insurance 1 (1) (2) (1)Investments 178 130 343 266Other (14) (15) (29) (31)Total income before income taxes $248 $107 $422 $226Identifiable assets: June 30, 2015 December 31, 2014Property casualty insurance $2,690 $2,656Life insurance 1,277 1,316Investments 14,606 14,441Other 315 340Total $18,888 $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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