| **Summary of Significant Accounting Policies** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       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| **Accounting Policies [Abstract]**             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                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| Summary of Significant Accounting Policies     | Note A. Summary of Significant Accounting PoliciesBasis of PresentationThe Consolidated Financial Statements include the accounts of CNA Financial Corporation (CNAF) and its subsidiaries. Collectively, CNAF and its subsidiaries are referred to as CNA or the Company.  Loews Corporation (Loews) owned approximately 90% of the outstanding common stock of CNAF as of December 31, 2012.The accompanying Consolidated Financial Statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP).  Intercompany amounts have been eliminated.  The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and the reported amounts of revenues and expenses during the reporting period.  Actual results may differ from those estimates.The Company has historically reported certain run-off insurance operations acquired in its merger with The Continental Corporation in 1995 as discontinued operations.  Due to the immateriality of the remaining liabilities, effective in the third quarter of 2011, the Company is no longer reporting these run-off operations as discontinued operations.BusinessThe Company's core property and casualty insurance operations are reported in three business segments: CNA Specialty, CNA Commercial and Hardy.  The Company's non-core operations are managed in two segments: Life & Group Non-Core and Corporate & Other Non-Core.The Company serves a wide variety of customers, including small, medium and large businesses; insurance companies; associations; professionals; groups; and individuals with a broad range of insurance and risk management products and services.Core insurance products include commercial property and casualty coverages, including surety.  Non-core insurance products, which primarily have been placed in run-off, include life and accident and health insurance and retirement products and annuities.  CNA services include risk management, information services, warranty and claims administration.  The Company's products and services are primarily marketed through independent agents, brokers, and managing general underwriters.Noncontrolling InterestsNet income attributable to noncontrolling interests for the years ended December 31, 2011 and 2010 represented the noncontrolling interests in CNA Surety Corporation (Surety) and First Insurance Company of Hawaii (FICOH).  On June 10, 2011, CNA completed the acquisition of the noncontrolling interest of Surety and on November 29, 2011, CNA completed the sale of its 50% ownership interest in FICOH.Insurance OperationsPremiums:  Insurance premiums on property and casualty insurance contracts are recognized in proportion to the underlying risk insured which principally are earned ratably over the duration of the policies.  Premiums on long term care contracts are earned ratably over the policy year in which they are due.  The reserve for unearned premiums represents the portion of premiums written relating to the unexpired terms of coverage.Insurance receivables include balances due currently or in the future, including amounts due from insureds related to losses under high deductible policies, and are presented at unpaid balances, net of an allowance for uncollectible receivables.  Amounts are considered past due based on policy payment terms.  That allowance is determined based on periodic evaluations of aged receivables, management's experience and current economic conditions.  Insurance receivables and any related allowance are written off after collection efforts are exhausted or a negotiated settlement is reached.Property and casualty contracts that are retrospectively rated contain provisions that result in an adjustment to the initial policy premium depending on the contract provisions and loss experience of the insured during the experience period.  For such contracts, the Company estimates the amount of ultimate premiums that the Company may earn upon completion of the experience period and recognizes either an asset or a liability for the difference between the initial policy premium and the estimated ultimate premium.  The Company adjusts such estimated ultimate premium amounts during the course of the experience period based on actual results to date.  The resulting adjustment is recorded as either a reduction of or an increase to the earned premiums for the period.Claim and claim adjustment expense reserves: Claim and claim adjustment expense reserves, except reserves for structured settlements not associated with asbestos and environmental pollution (A&EP), workers' compensation lifetime claims, and accident and health claims, are not discounted and are based on 1) case basis estimates for losses reported on direct business, adjusted in the aggregate for ultimate loss expectations; 2) estimates of incurred but not reported (IBNR) losses; 3) estimates of losses on assumed reinsurance; 4) estimates of future expenses to be incurred in the settlement of claims; 5) estimates of salvage and subrogation recoveries and 6) estimates of amounts due from insureds related to losses under high deductible policies.  Management considers current conditions and trends as well as past Company and industry experience in establishing these estimates.  The effects of inflation, which can be significant, are implicitly considered in the reserving process and are part of the recorded reserve balance.  Ceded claim and claim adjustment expense reserves are reported as a component of Reinsurance receivables on the Consolidated Balance Sheets.  Claim and claim adjustment expense reserves are presented net of anticipated amounts due from insureds related to losses under deductible policies of $1.3 billion and $1.4 billion as of December 31, 2012 and 2011.  A significant portion of these amounts are supported by collateral.  The Company has an allowance for uncollectible deductible amounts, which is presented as a component of the allowance for doubtful accounts included in Insurance receivables on the Consolidated Balance Sheets.Structured settlements have been negotiated for certain property and casualty insurance claims.  Structured settlements are agreements to provide fixed periodic payments to claimants.  Certain structured settlements are funded by annuities purchased from Continental Assurance Company (CAC) for which the related annuity obligations are reported in Future policy benefits reserves.  Obligations for structured settlements not funded by annuities are included in claim and claim adjustment expense reserves and carried at present values determined using interest rates ranging from 7.1% to 9.7% at December 31, 2012 and 5.5% to 8.0% at December 31, 2011.  At December 31, 2012 and 2011, the discounted reserves for unfunded structured settlements were $602 million and $632 million, net of discount of $1.0 billion and $1.1 billion.Workers' compensation lifetime claim reserves are calculated using mortality assumptions determined through statutory regulation and economic factors.  Accident and health claim reserves are calculated using mortality and morbidity assumptions based on Company and industry experience.  Workers' compensation lifetime claim reserves and accident and health claim reserves are discounted at interest rates ranging from 3.0% to 6.5% at both December 31, 2012 and 2011.  At December 31, 2012 and 2011, such discounted reserves totaled $2.2 billion and $2.1 billion, net of discount of $837 million and $520 million.Future policy benefits reserves: Reserves for long term care products and payout annuity contracts are computed using the net level premium method, which incorporates actuarial assumptions as to morbidity, mortality, persistency, discount rates, which are impacted by expected investment yields, and expenses.  Expense assumptions include the estimated effects of expenses to be incurred beyond the premium paying period.  Actuarial assumptions generally vary by plan, age at issue and policy duration.  The initial assumptions are determined at issuance, include a margin for adverse deviation, and are locked in throughout the life of the contract unless a premium deficiency develops.  If a premium deficiency emerges, the assumptions are unlocked and deferred acquisition costs, if any, and the future policy benefit reserves are adjusted.  Interest rates for long-term care products range from 5.0% to 7.4% at December 31, 2012 and from 5.0% to 7.5% at December 31, 2011.  Interest rates for payout annuity contracts range from 5.0% to 8.7% at December 31, 2012 and from 5.4% to 7.5% at December 31, 2011.  In 2012, the Company unlocked assumptions related to its payout annuity contracts due to anticipated adverse changes in discount rates, which reflect the current low interest rate environment and our view of expected investment yields, resulting in loss recognition which increased insurance liabilities by $33 million.  In 2011, the Company unlocked assumptions related to its payout annuity contracts due to anticipated adverse changes in mortality and discount rates, resulting in loss recognition which increased insurance reserves by $166 million.Policyholders' funds reserves: Policyholders' funds reserves primarily include reserves for investment contracts without life contingencies.  For these contracts, policyholder liabilities are generally equal to the accumulated policy account values, which consist of an accumulation of deposit payments plus credited interest, less withdrawals and amounts assessed through the end of the period.Guaranty fund and other insurance-related assessments: Liabilities for guaranty fund and other insurance-related assessments are accrued when an assessment is probable, when it can be reasonably estimated, and when the event obligating the entity to pay an imposed or probable assessment has occurred.  Liabilities for guaranty funds and other insurance-related assessments are not discounted and are included as part of Other liabilities on the Consolidated Balance Sheets.  As of December 31, 2012 and 2011, the liability balances were $143 million and $152 million.  As of December 31, 2012 and 2011, included in Other assets on the Consolidated Balance Sheets were $2 million of related assets for premium tax offsets.  This asset is limited to the amount that is able to be offset against premium tax on future premium collections from business written or committed to be written.Reinsurance:  Reinsurance accounting allows for contractual cash flows to be reflected as premiums and losses.  To qualify for reinsurance accounting, reinsurance agreements must include risk transfer.  To meet risk transfer requirements, a reinsurance contract must include both insurance risk, consisting of underwriting and timing risk, and a reasonable possibility of a significant loss for the assuming entity.Reinsurance receivables related to paid losses are presented at unpaid balances.  Reinsurance receivables related to unpaid losses are estimated in a manner consistent with claim and claim adjustment expense reserves or future policy benefits reserves.  Reinsurance receivables are reported net of an allowance for uncollectible amounts on the Consolidated Balance Sheets.  The cost of reinsurance is primarily accounted for over the life of the underlying reinsured policies using assumptions consistent with those used to account for the underlying policies or over the reinsurance contract period.  The ceding of insurance does not discharge the primary liability of the Company.The Company has established an allowance for uncollectible reinsurance receivables which relates to both amounts already billed on ceded paid losses as well as ceded reserves that will be billed when losses are paid in the future.  The allowance for uncollectible reinsurance receivables is estimated on the basis of periodic evaluations of balances due from reinsurers, reinsurer solvency, management's experience and current economic conditions.  Reinsurer financial strength ratings are updated and reviewed on an annual basis or sooner if the Company becomes aware of significant changes related to a reinsurer.  Because billed receivables are generally 5% or less of total reinsurance receivables, the age of the reinsurance receivables related to paid losses is not a significant input into the allowance analysis.  Changes in the allowance for uncollectible reinsurance receivables are presented as a component of Insurance claims and policyholders' benefits on the Consolidated Statements of Operations.Amounts are considered past due based on the reinsurance contract terms.  Reinsurance receivables related to paid losses and any related allowance are written off after collection efforts have been exhausted or a negotiated settlement is reached with the reinsurer. Reinsurance receivables related to paid losses from insolvent insurers are written off when the settlement due from the estate can be reasonably estimated.  At the time reinsurance receivables related to paid losses are written off, any required adjustment to reinsurance receivables related to unpaid losses is recorded as a component of Insurance claims and policyholders' benefits on the Consolidated Statements of Operations.Reinsurance contracts that do not effectively transfer the economic risk of loss on the underlying policies are recorded using the deposit method of accounting, which requires that premium paid or received by the ceding company or assuming company be accounted for as a deposit asset or liability.  The Company had $3 million and $18 million recorded as deposit assets at December 31, 2012 and 2011, and $125 million and $123 million recorded as deposit liabilities at December 31, 2012 and 2011.  Income on reinsurance contracts accounted for under the deposit method is recognized using an effective yield based on the anticipated timing of payments and the remaining life of the contract.  When the anticipated timing of payments changes, the effective yield is recalculated to reflect actual payments to date and the estimated timing of future payments.  The deposit asset or liability is adjusted to the amount that would have existed had the new effective yield been applied since the inception of the contract.Participating insurance: Policyholder dividends are accrued using an estimate of the amount to be paid based on underlying contractual obligations under policies and applicable state laws.  Limitations exist on the amount of income from participating life insurance contracts that may be distributed to stockholders, and therefore the share of income on these policies that cannot be distributed to stockholders is excluded from Stockholders' equity by a charge to operations and other comprehensive income and the establishment of a corresponding liability.Deferred acquisition costs: Acquisition costs include commissions, premium taxes and certain underwriting and policy issuance costs which are incremental direct costs of successful contract acquisitions.  Deferred acquisition costs related to long term care contracts issued prior to January 1, 2004 include costs which vary with and are primarily related to the acquisition of business, as further discussed at the Accounting Standards Update section of this note.Acquisition costs related to property and casualty business are deferred and amortized ratably over the period the related premiums are earned.Deferred acquisition costs related to long term care contracts are amortized over the premium-paying period of the related policies using assumptions consistent with those used for computing future policy benefit reserves for such contracts.  Assumptions are made at the date of policy issuance or acquisition and are consistently applied during the lives of the contracts.  Deviations from estimated experience are included in results of operations when they occur.  For these contracts, the amortization period is typically the estimated life of the policy.  At December 31, 2012 and 2011, Deferred acquisition costs were presented net of Shadow Adjustments, as defined later in this note, of $369 million and $398 million.The Company evaluates deferred acquisition costs for recoverability.  Anticipated investment income is considered in the determination of the recoverability of deferred acquisition costs.  Adjustments, if necessary, are recorded in current results of operations.Deferred acquisition costs are presented net of ceding commissions and other ceded acquisition costs.  Unamortized deferred acquisition costs relating to contracts that have been substantially changed by a modification in benefits, features, rights or coverages that were not anticipated in the original contract are not deferred and are included as a charge to operations in the period during which the contract modification occurred.Investments in life settlement contracts and related revenue recognition:  Prior to 2002, the Company purchased investments in life settlement contracts.  A life settlement contract is a contract between the owner of a life insurance policy (the policy owner) and a third-party investor (investor).  Under a life settlement contract, the Company obtains the ownership and beneficiary rights of an underlying life insurance policy.The Company accounts for its investments in life settlement contracts using the fair value method.  Under the fair value method, each life settlement contract is carried at its fair value at the end of each reporting period.  The change in fair value, life insurance proceeds received and periodic maintenance costs, such as premiums, necessary to keep the underlying policy in force, are recorded in Other revenues on the Consolidated Statements of Operations.  The fair value of the Company's investments in life settlement contracts were $100 million and $117 million at December 31, 2012 and 2011, and are included in Other assets on the Consolidated Balance Sheets.  The cash receipts and payments related to life settlement contracts are included in Cash flows from operating activities on the Consolidated Statements of Cash Flows.The following table details the values for life settlement contracts.  The determination of fair value is discussed in Note E.December 31, 2012Number of Life Settlement Contracts Fair Value of Life Settlement  Contracts(In millions) Face Amount of Life Insurance Policies(In millions)Estimated maturity during:     201370 $15 $41201460 13 36201560 11 34201650 9 30201740 7 27Thereafter390 45 237Total670 $100 $405The Company uses an actuarial model to estimate the aggregate face amount of life insurance that is expected to mature in each future year and the corresponding fair value.  This model projects the likelihood of the insured's death for each inforce policy based upon the Company's estimated mortality rates, which may vary due to the relatively small size of the portfolio of life settlement contracts.  The number of life settlement contracts presented in the table above is based upon the average face amount of inforce policies estimated to mature in each future year.The increase in fair value recognized for the years ended December 31, 2012, 2011 and 2010 on contracts still being held was $11 million, $5 million and $10 million.  The gains recognized during the years ended December 31, 2012, 2011 and 2010 on contracts that settled were $42 million, $28 million and $19 million.Separate Account Business: Separate account assets and liabilities represent contract holder funds related to investment and annuity products for which the policyholder assumes substantially all the risk and reward.  The assets are segregated into accounts with specific underlying investment objectives and are legally segregated from the Company.  All assets of the separate account business are carried at fair value with an equal amount recorded for separate account liabilities.  Fee income accruing to the Company related to separate accounts is primarily included within Other revenues on the Consolidated Statements of Operations.A number of separate account pension deposit contracts guarantee principal and an annual minimum rate of interest.  If aggregate contract value in the separate account exceeds the fair value of the related assets, an additional Policyholders' funds liability is established.  During 2012 and 2010, the Company decreased this pretax Policyholders' funds liability by $20 million and $24 million.  The Company increased this pretax Policyholders' funds liability by $18 million in 2011.  Certain of these contracts are subject to a fair value adjustment if terminated by the policyholder.InvestmentsThe Company classifies its fixed maturity securities and its equity securities as either available-for-sale or trading, and as such, they are carried at fair value.  Changes in fair value of trading securities are reported within Net investment income on the Consolidated Statements of Operations.  Changes in fair value related to available-for-sale securities are reported as a component of Other comprehensive income.  The cost of fixed maturity securities classified as available-for-sale is adjusted for amortization of premiums and accretion of discounts to maturity, which are included in Net investment income on the Consolidated Statements of Operations.  Losses may be recognized within Net realized investment gains (losses) on the Consolidated Statements of Operations when a decline in value is determined by the Company to be other-than-temporary.To the extent that unrealized gains on fixed income securities supporting long term care products and payout annuity contracts would result in a premium deficiency if those gains were realized, a related decrease in Deferred acquisition costs and/or increase in Insurance reserves are recorded, net of tax, as a reduction of net unrealized gains through Other comprehensive income (Shadow Adjustments).  For the years ended December 31, 2012 and 2011, Shadow Adjustments, net of participating policyholders' interest, of $789 million and $572 million, were recorded, net of tax.  At December 31, 2012 and 2011, net unrealized gains on investments included in Accumulated other comprehensive income (AOCI) were correspondingly reduced by $1,511 million and $722 million.For asset-backed securities included in fixed maturity securities, the Company recognizes income using an effective yield based on anticipated prepayments and the estimated economic life of the securities.  When estimates of prepayments change, the effective yield is recalculated to reflect actual payments to date and anticipated future payments.  The amortized cost of high credit quality securities is adjusted to the amount that would have existed had the new effective yield been applied since the acquisition of the securities.  Such adjustments are reflected in Net investment income on the Consolidated Statements of Operations. Interest income on lower rated securities is determined using the prospective yield method.The Company's carrying value of investments in limited partnerships is its share of the net asset value of each partnership, as determined by the General Partner.  Certain partnerships for which results are not available on a timely basis are reported on a lag, primarily three months or less.  Changes in net asset values are accounted for under the equity method and recorded within Net investment income on the Consolidated Statements of Operations.Mortgage loans are commercial in nature, are carried at unpaid principal balance, net of unamortized fees and any valuation allowance, and are recorded once funded.  Mortgage loans are considered to be impaired loans when it is probable that contractual principal and interest payments will not be collected.  A valuation allowance is established for impaired loans to the extent that the present value of expected future cash flows discounted at the loan's original effective interest rate is less than the carrying value of the loan.  Interest income from mortgage loans is recognized on an accrual basis using the effective yield method.  Accrual of income is generally suspended for mortgage loans that are impaired and collection of principal and interest payments is unlikely.  Mortgage loans are considered past due when full principal or interest payments have not been received according to contractual terms.Other invested assets are carried at fair value and include overseas deposits, certain derivative securities and securities containing embedded credit derivatives for which the fair value option was elected.  Overseas deposits are primarily short-term government securities, agency securities, and corporate bonds held in trusts that are managed by Lloyd's of London (Lloyd's).  These funds are required of Lloyd's syndicates to protect policyholders in overseas markets and may be denominated in local currency.  Changes in fair value of overseas deposits are reflected in Net investment income on the Consolidated Statements of Operations.  Changes in fair value of certain derivative securities and securities containing embedded credit derivatives for which the fair value option was elected are reported in Net realized investment gains (losses) in the Consolidated Statements of Operations.Short term investments are carried at fair value, with the exception of cash accounts earning interest, which are carried at cost and approximate fair value.  Changes in fair value are reported as a component of Other comprehensive income.Purchases and sales of all securities are recorded on the trade date, except for private placement debt securities, including bank loan participations, which are recorded once funded.  Realized investment gains and losses are determined on the basis of the cost or amortized cost of the specific securities sold.Income TaxesThe Company and its eligible subsidiaries (CNA Tax Group) are included in the consolidated federal income tax return of Loews and its eligible subsidiaries.  The Company accounts for income taxes under the asset and liability method.  Under the asset and liability method, deferred income taxes are recognized for temporary differences between the financial statement and tax return bases of assets and liabilities, based on enacted tax rates and other provisions of the tax law.  The effect of a change in tax laws or rates on deferred tax assets and liabilities is recognized in income in the period in which such change is enacted.  Future tax benefits are recognized to the extent that realization of such benefits is more likely than not, and a valuation allowance is established for any portion of a deferred tax asset that management believes will not be realized.Pension and Postretirement BenefitsThe Company recognizes the overfunded or underfunded status of its defined benefit plans in Other assets or Other liabilities on the Consolidated Balance Sheets.  Changes in funded status related to prior service costs and credits and actuarial gains and losses are recognized in the year in which the changes occur through Other comprehensive income.  Annual service cost, interest cost, expected return on plan assets, amortization of prior service costs and credits, and amortization of actuarial gains and losses are recognized on the Consolidated Statements of Operations.  Stock-Based CompensationThe Company records compensation expense using the fair value method for all awards it grants, modifies, repurchases or cancels primarily on a straight-line basis over the requisite service period, generally four years.Foreign CurrencyForeign currency translation gains and losses are reflected in Stockholders' equity as a component of Accumulated other comprehensive income.  The Company's foreign subsidiaries' balance sheet accounts are translated at the exchange rates in effect at each year end and income statement accounts are either translated at the exchange rate on the date of the transaction or at the average exchange rates.  Foreign currency transaction gains (losses) of $12 million, $4 million and $(19) million were included in determining net income (loss) for the years ended December 31, 2012, 2011 and 2010.Property and EquipmentProperty and equipment are carried at cost less accumulated depreciation.  Depreciation is based on the estimated useful lives of the various classes of property and equipment and is determined principally on the straight-line method.  Furniture and fixtures are depreciated over seven years.  Office equipment is depreciated over five years.  The estimated lives for data processing equipment and software range from three to five years.  Leasehold improvements are depreciated over the corresponding lease terms not to exceed the underlying asset life.  The Company's owned buildings, and related capital improvements, are depreciated over periods not to exceed fifty years. GoodwillGoodwill represents the excess of purchase price over the fair value of the net assets of acquired entities and businesses.  Goodwill related to Hardy may change from period to period as a result of foreign currency translation.  Goodwill is tested for impairment annually or when certain triggering events require such tests.  See Note B to the Consolidated Financial Statements for further discussion of the goodwill recognized as part of the acquisition of Hardy.Intangible AssetsIntangible assets are reported within Other assets.  As of December 31, 2012, the Company's finite-lived intangible assets were $40 million.  The Company had no finite-lived intangible assets at December 31, 2011.  Finite-lived intangible assets are amortized over their estimated useful lives.  As of December 31, 2012, and 2011, the Company's indefinite-lived intangible assets were $73 million and $16 million.  Indefinite-lived intangible assets are tested for impairment annually or when certain triggering events require such tests.  See Note B to the Consolidated Financial Statements for further discussion of the intangible assets acquired as part of the acquisition of Hardy.Earnings (Loss) Per Share DataEarnings (loss) per share attributable to the Company's common stockholders is based on weighted average number of outstanding common shares.  Basic earnings (loss) per share excludes the impact of dilutive securities and is computed by dividing net income (loss) attributable to CNA by the weighted average number of common shares outstanding for the period.  Diluted earnings (loss) per share reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock.For the years ended December 31, 2012, 2011, and 2010, approximately 417 thousand, 290 thousand and 380 thousand potential shares attributable to exercises under stock-based employee compensation plans were included in the calculation of diluted earnings per share.  For those same periods, approximately 730 thousand, 1.1 million and 1.2 million potential shares attributable to exercises under stock-based employee compensation plans were not included in the calculation of diluted earnings per share because the effect would have been antidilutive.Supplementary Cash Flow InformationCash payments made for interest were $170 million, $175 million and $145 million for the years ended December 31, 2012, 2011 and 2010.  Cash refunds received for income taxes were $29 million and $175 million for the years ended December 31, 2012 and 2010.  Cash payments made for income taxes were $61 million for the year ended December 31, 2011.Accounting Standards UpdatesAdoptedAccounting for Costs Associated with Acquiring or Renewing Insurance ContractsIn October 2010, the Financial Accounting Standards Board issued updated accounting guidance which limits the capitalization of costs incurred to acquire or renew insurance contracts to those that are incremental direct costs of successful contract acquisitions.  The previous guidance allowed the capitalization of acquisition costs that vary with and are primarily related to the acquisition of new and renewal insurance contracts, whether the costs related to successful or unsuccessful efforts.As of January 1, 2012, the Company adopted the updated accounting guidance prospectively as of January 1, 2004, the earliest date practicable.  Due to the lack of available historical data related to certain accident and health contracts issued prior to January 1, 2004, a full retrospective application of the change in accounting guidance was impracticable.  Acquisition costs capitalized prior to January 1, 2004 will continue to be accounted for under the previous accounting guidance and will be amortized over the premium-paying period of the related policies using assumptions consistent with those used for computing future policy benefit reserves for such contracts.For the year ended December 31, 2012, the adoption of the new accounting guidance resulted in a $5 million decrease in Net income attributable to CNA and a $0.02 decrease in Basic and Diluted earnings per share attributable to CNA common stockholders.The Company has adjusted its previously reported financial information included herein to reflect the change in accounting guidance for deferred acquisition costs.  The impacts of adopting the new accounting standard on the Company's Consolidated Balance Sheet as of December 31, 2011 were a $106 million decrease in Deferred acquisition costs and a $37 million increase in Deferred income taxes.  The impacts to Accumulated other comprehensive income (AOCI) and Additional paid-in capital were the result of the indirect effects of the Company's adoption of this guidance on Shadow Adjustments and the Company's acquisition of the noncontrolling interest of Surety as discussed above.The impacts on the Company's Consolidated Statements of Operations for the years ended December 31, 2011 and 2010 were a $2 million increase and no impact in Other net realized investment gains, a $234 million and $219 million decrease in Amortization of deferred acquisition costs, a $242 million and $219 million increase in Other operating expenses, a $4 million and $1 million decrease in Income tax expense, resulting in a $2 million decrease and a $1 million increase in Net income attributable to CNA, and a $0.01 decrease and no impact in Basic and Diluted earnings per share attributable to CNA common stockholders.There were no changes to net cash flows from operating, investing or financing activities for the comparative periods presented as a result of the adoption of the new accounting standard. |

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The entire disclosure for all significant accounting policies of the reporting entity.
+ References
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