| **Commitments and Contingent Liabilities**              | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Commitments and Contingencies Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Commitments and Contingent Liabilities                  | Commitments and Contingent LiabilitiesThe company, through its insurance subsidiaries, is involved in claims litigation arising in the ordinary course of conducting its business, both as a liability insurer defending or providing indemnity for third-party claims brought against insureds and as an insurer defending coverage claims brought against it. The company accounts for such activity through the establishment of unpaid loss and loss expense reserves. Subject to the uncertainties discussed in Note 4, Property Casualty Loss and Loss Expenses, and in the discussion in the balance of this Note, we believe that the ultimate liability, if any, with respect to such ordinary-course claims litigation, after consideration of provisions made for potential losses, costs of defense, and reinsurance recoveries, is immaterial to our consolidated financial position, results of operations and cash flows.The company and its subsidiaries also are occasionally involved in other legal and regulatory proceedings, some of which assert claims for substantial amounts. These actions include, among others, putative class actions seeking certification of state or national classes. Such proceedings have alleged, for example, improper depreciation of labor costs in repair estimates. The company’s insurance subsidiaries also are occasionally parties to individual actions in which extra-contractual damages, punitive damages or penalties are sought, such as claims alleging bad faith handling of insurance claims or writing unauthorized coverage or claims alleging discrimination by former or current associates.On a quarterly basis, we review these outstanding matters. Under current accounting guidance, we establish accruals when it is probable that a covered loss has been incurred and we can reasonably estimate its potential exposure.  The company accounts for such probable and estimable losses, if any, through the establishment of legal expense reserves. Based on our quarterly review, we believe that our accruals for probable and estimable losses are reasonable and that the amounts accrued do not have a material effect on our consolidated financial position, results of operations and cash flows. However, if any one or more of these matters results in a judgment against us or settlement for an amount that is significantly greater than the amount accrued, the resulting liability could have a material effect on the company’s consolidated financial position, results of operations and cash flows. Based on our most recent review, our estimate for any other matters for which the risk of loss is not probable, but more than remote, is immaterial. |

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No definition available.
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| - Definition
The entire disclosure for commitments and contingencies.
+ References
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