| **Summary Of Investments Other Than Investments In Related Parties**             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Summary of Investments, Other than Investments in Related Parties [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Summary Of Investments Other Than Investments In Related Parties                 | Schedule ICincinnati Financial Corporation and SubsidiariesSummary of Investments - Other Than Investments in Related Parties(In millions) At December 31, 2013Type of investment Cost oramortized cost Fairvalue Balance sheetFixed maturities:      States, municipalities and political subdivisions:      The Cincinnati Insurance Company $2,569 $2,648 $2,648The Cincinnati Casualty Company 122 127 127The Cincinnati Indemnity Company 32 33 33The Cincinnati Life Insurance Company 193 205 205The Cincinnati Specialty Underwriters Insurance Company 190 197 197CSU Producer Resources Inc. 1 1 1Total 3,107 3,211 3,211Convertibles and bonds with warrants attached:      The Cincinnati Insurance Company 17 17 17Total 17 17 17United States government:      The Cincinnati Insurance Company 1 1 1The Cincinnati Casualty Company 1 1 1The Cincinnati Indemnity Company 1 1 1The Cincinnati Life Insurance Company 4 4 4Total 7 7 7Government-sponsored enterprises:      The Cincinnati Life Insurance Company 212 186 186The Cincinnati Insurance Company 15 14 14Total 227 200 200Foreign government:      The Cincinnati Insurance Company 10 10 10Total 10 10 10All other corporate bonds:      The Cincinnati Insurance Company 2,518 2,726 2,726The Cincinnati Casualty Company 114 121 121The Cincinnati Indemnity Company 28 29 29The Cincinnati Specialty Underwriters Insurance Company 162 169 169The Cincinnati Life Insurance Company 2,382 2,551 2,551CSU Producer Resources Inc. 5 5 5Cincinnati Financial Corporation 61 75 75Total 5,270 5,676 5,676Total fixed maturities $8,638 $9,121 $9,121        Schedule I (continued)Cincinnati Financial Corporation and SubsidiariesSummary of Investments - Other Than Investments in Related Parties(In millions) At December 31, 2013Type of investment Cost oramortized cost Fairvalue Balance sheetEquity securities:      Common stocks:      The Cincinnati Insurance Company $1,437 $2,659 $2,659The Cincinnati Casualty Company 47 89 89The Cincinnati Indemnity Company 13 22 22The Cincinnati Specialty Underwriters Insurance Company 48 74 74CSU Producer Resources Inc. 4 6 6Cincinnati Financial Corporation 847 1,363 1,363Total 2,396 4,213 4,213Nonredeemable preferred stocks:      The Cincinnati Insurance Company 117 146 146The Cincinnati Life Insurance Company 7 13 13Cincinnati Financial Corporation 3 3 3Total 127 162 162Total equity securities $2,523 $4,375 $4,375Other invested assets:      Policy loans:      The Cincinnati Life Insurance Company $36 — $36Private equity:      Cincinnati Financial Corporation 32 — 32Total other invested assets $68 — $68Total investments $11,229 — $13,564        |

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| - Definition
The entire disclosure for the schedule applicable to insurance companies summarizing investments held as of the most recent audited balance sheet. At a minimum, such summary is by three major categories of investments including: (1) fixed maturities primarily consisting of bonds, including convertibles and bonds with warrants, and redeemable preferred stocks, (2) equity securities primarily consisting of common stocks and nonredeemable preferred stocks, and (3) other investments including mortgage loans on real estate, real estate held for investment, real estate acquired in satisfaction of debt, policy loans, other long-term investments, and short-term investments not otherwise categorized. The information provided with respect to each item within each category includes: (A) the original cost of equity securities and, as to fixed maturity securities, original cost reduced by repayments and adjusted for amortization of premiums or accrual of discounts, (B) fair value as of the reporting date, and (C) the amount at which the item within each category is shown in the statement of financial position; with respect to (C), if the amount at which shown in the statement of financial position is different from the items original [amortized] cost or fair value, an explanation of the difference may be included herein.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 15 -Article 12Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 320 -Section S99 -Paragraph 7 -Subparagraph (SX 210.12-15) -URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611379-123010
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