| **Segment Information**          | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
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| **Segment Reporting [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Segment Information              | SEGMENT INFORMATION We 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: •Commercial lines property casualty insurance•Personal lines property casualty insurance•Excess and surplus lines property casualty insurance•Life insurance•InvestmentsWe report as Other the noninvestment operations of the parent company and its noninsurer subsidiary, CFC Investment Company. See our 2012 Annual Report on Form 10-K, Item 8, Note 18, Segment Information, Page 137, 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: (In millions) Three months ended June 30, Six months ended June 30,  2013 2012 2013 2012Revenues:        Commercial lines insurance        Commercial casualty $211 $191 $415 $372Commercial property 152 134 299 265Commercial auto 117 106 231 207Workers' compensation 87 85 175 166Specialty packages 37 37 76 75Surety and executive risk 30 27 59 54Machinery and equipment 11 10 21 19Commercial lines insurance premiums 645 590 1,276 1,158Fee revenue 1 1 1 2Total commercial lines insurance 646 591 1,277 1,160Personal lines insurance        Personal auto 109 100 216 198Homeowner 99 87 195 171Other personal lines 29 27 57 54Personal lines insurance premiums 237 214 468 423Fee revenue 1 1 1 1       Total personal lines insurance 238 215 469 424         Excess and surplus lines insurance 28 22 55 43         Life insurance 44 51 86 92     Separate account investment management fees 1 — 2 —             Total life insurance 45 51 88 92         Investment operations             Investment income, net of expenses 131 132 259 263     Realized investment gains, net 14 6 55 19             Total investment revenue 145 138 314 282         Other 2 3 4 5Total revenues $1,104 $1,020 $2,207 $2,006Income (loss) before income taxes:        Insurance underwriting results        Commercial lines insurance $34 $(20) $92 $14Personal lines insurance (1) (55) 19 (77)Excess and surplus lines insurance 1 (2) 1 (5)Life insurance 3 2 10 (1)Investment operations 127 118 275 241Other (16) (14) (32) (31)Total $148 $29 $365 $141Identifiable assets: June 30, 2013 December 31, 2012Property casualty insurance $2,489 $2,395Life insurance 1,254 1,201Investment operations 12,983 12,599Other 308 353Total $17,034 $16,548 |

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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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