| **Accounting Policies**            | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    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| **Accounting Policies [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   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| Accounting Policies                | Accounting PoliciesThe condensed consolidated financial statements include the accounts of Cincinnati Financial Corporation and its consolidated subsidiaries, each of which is wholly owned. These statements are presented in conformity with accounting principles generally accepted in the United States of America (GAAP). All intercompany balances and transactions have been eliminated in consolidation. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Our actual results could differ from those estimates. Our December 31, 2014, condensed consolidated balance sheet amounts are derived from the audited financial statements but do not include all disclosures required by GAAP. Our September 30, 2015, condensed consolidated financial statements are unaudited. Certain financial information that is included in annual financial statements prepared in accordance with GAAP is not required for interim reporting and has been condensed or omitted. We believe that we have made all adjustments, consisting only of normal recurring accruals, that are necessary for fair presentation. These condensed consolidated financial statements should be read in conjunction with our consolidated financial statements included in our 2014 Annual Report on Form 10-K. The results of operations for interim periods do not necessarily indicate results to be expected for the full year.Pending Accounting UpdatesASU 2014-09 Revenue from Contracts with Customers In May 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers. ASU 2014-09 requires an entity to recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods and services. Insurance contracts do not fall within the scope of this ASU. The effective date of ASU 2014-09 is for annual reporting periods beginning after December 15, 2017. In July 2015, the FASB decided to defer by one year the effective date of this ASU. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service PeriodIn June 2014, the FASB issued ASU 2014-12, Compensation-Stock Compensation: Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period. ASU 2014-12 requires that performance targets that affect vesting and that could be achieved after the requisite service period be treated as performance conditions. The effective date of ASU 2014-12 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.ASU 2015-02, Consolidation-Amendments to the Consolidation AnalysisIn February 2015, the FASB issued ASU 2015-02, Consolidation-Amendments to the Consolidation Analysis. ASU 2015-02 makes amendments to the current consolidation guidance, focusing mainly on the investment management industry; however, entities across all industries may be impacted. The effective date of ASU 2015-02 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.ASU 2015-03, Interest-Imputation of InterestIn April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest. ASU 2015-03 reduces the complexity of disclosing debt issuance costs and debt discount and premium on the balance sheet by requiring that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The effective date of ASU 2015-03 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations.ASU 2015-09, Financial Services-Insurance: Disclosures about Short-Duration ContractsIn May 2015, the FASB issued ASU 2015-09, Financial Services-Insurance: Disclosures About Short-Duration Contracts. ASU 2015-09 requires entities to provide additional disclosures about the liability for unpaid claims and claim adjustment expenses to increase the transparency of significant estimates. ASU 2015-09 also requires entities to disclose information about significant changes in methodologies and assumptions used to calculate the liability for unpaid claims and claim adjustment expenses, including reasons for the change and the effects on the financial statements.  ASU 2015-09 also requires entities to disclose a rollforward of the liability of unpaid claims and claim adjustment expense for annual and interim reporting periods. The effective date of ASU 2015-09 is for annual reporting periods beginning after December 15, 2015, and interim reporting periods within annual period beginning after December 15, 2016. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations, but the ASU will require additional disclosures to our annual and interim reporting periods.ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements.In August 2015, the FASB issued ASU 2015-15, Interest-Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU 2015-15 allows entities to defer and present debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The effective date of ASU 2015-15 is for interim and annual reporting periods beginning after December 15, 2015. The ASU has not yet been adopted and will not have a material impact on our company’s financial position, cash flows or results of operations. |

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No definition available.
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| - Definition
The entire disclosure for all significant accounting policies of the reporting entity.
+ References
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