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| **Segment Reporting [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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| 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.•Commercial lines property casualty insurance•Personal lines property casualty insurance•Excess and surplus lines property casualty insurance•Life insurance•Investment operationsDuring 2013, we renamed the line of business surety and executive risk in the commercial segment to management liability and surety.We report as Other the noninvestment operations of the parent company and its noninsurer subsidiary, CFC Investment Company.Revenues come primarily from unaffiliated customers:•All four insurance segments record revenues from insurance premiums earned. Life insurance segment revenues also include separate account investment management fees.•Fee revenues for the commercial and personal insurance segments primarily represent installment fees.•Our investment operations’ revenues consist of pretax net investment income and realized investment gains and losses.•Other revenues are primarily finance income.Income or loss before income taxes for each segment is reported based on the nature of that business area’s operations:•Income before income taxes for the insurance segments is defined as underwriting profit or loss.◦For commercial lines, personal lines and excess and surplus lines insurance segments, we calculate underwriting profit or loss as premiums earned and fee revenue minus loss and loss expenses and underwriting expenses incurred.◦For the life insurance segment, we calculate underwriting profit or loss as premiums earned and separate account investment management fees, minus contract holders’ benefits and expenses incurred, plus investment interest credited to contract holders.•Income before income taxes for the investment operations segment is net investment income plus realized investment gains and losses for investments of the entire company, minus investment interest credited to contract holders of the life insurance segment.•Loss before income taxes for the Other category is primarily due to interest expense from debt of the parent company and operating expenses of our headquarters.Identifiable assets are used by each segment in its operations. We do not separately report the identifiable assets for the commercial, personal or excess and surplus lines segments because we do not use that measure to analyze the segments. We include all investment assets, regardless of ownership, in the investment operations segment. This table summarizes segment information:(In millions) Years ended December 31,  2013 2012 2011Revenues:      Commercial lines insurance      Commercial casualty $856 $767 $711Commercial property 623 545 497Commercial auto 479 426 394Workers' compensation 365 344 318Specialty packages 150 151 138Management liability and surety 119 111 103Machinery and equipment 44 39 36Commercial lines insurance premiums 2,636 2,383 2,197Fee revenue 3 4 3Total commercial lines insurance 2,639 2,387 2,200       Personal lines insurance      Personal auto 443 404 368Homeowner 403 353 294Other personal lines 115 111 100Personal lines insurance premiums 961 868 762Fee revenue 1 2 1Total personal lines insurance 962 870 763       Excess and surplus lines insurance 116 93 70       Life insurance premiums 189 178 165Separate account investment management fees 4 1 2Total life insurance 193 179 167       Investment operations      Investment income, net of expenses 529 531 525Realized investment gains, net 83 42 70Total investment revenue 612 573 595       Other 9 9 8Total revenues $4,531 $4,111 $3,803       Income (loss) before income taxes:      Insurance underwriting results:      Commercial lines insurance $186 $181 $(102)Personal lines insurance 33 (43) (182)Excess and surplus lines insurance 14 (1) 6Life insurance 9 (3) (3)Investment operations 532 491 514Other (60) (59) (60)Total income before income taxes $714 $566 $173       Identifiable assets: December 31, December 31,    2013 2012  Property casualty insurance $2,455 $2,395  Life insurance 1,225 1,201  Investment operations 13,618 12,599  Other 364 353  Total $17,662 $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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