| **Investments (Fair Values And Unrealized Losses By Investment Category And By The Duration Of The Securities' Continuous Unrealized Loss Position) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2014                                                                                                                                                                                                                                                                         | Dec. 31, 2013                                                                                                                                                                                                                                                                         |
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| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | $ 393us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue                                                                                                                                                                                  | $ 1,516us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue                                                                                                                                                                                |
| Less than 12 months unrealized losses                                                                                                                                                                          | 11cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3                                                                                                                                                                                       | 74cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3                                                                                                                                                                                       |
| 12 months or more fair value                                                                                                                                                                                   | 446us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue                                                                                                                                                                                    | 86us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue                                                                                                                                                                                     |
| 12 months or more unrealized losses                                                                                                                                                                            | 11cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3                                                                                                                                                                                       | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3                                                                                                                                                                                        |
| Total fair value                                                                                                                                                                                               | 839us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue                                                                                                                                                                                                        | 1,602us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue                                                                                                                                                                                                      |
| Total unrealized losses                                                                                                                                                                                        | 22cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3                                                                                                                                                                                                       | 79cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3                                                                                                                                                                                                       |
| Fixed Maturities                                                                                                                                                                                               |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 292us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                | 1,397us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                              |
| Less than 12 months unrealized losses                                                                                                                                                                          | 8cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                    | 70cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                   |
| 12 months or more fair value                                                                                                                                                                                   | 429us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                | 86us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                 |
| 12 months or more unrealized losses                                                                                                                                                                            | 10cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                   | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                    |
| Total fair value                                                                                                                                                                                               | 721us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                    | 1,483us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                  |
| Total unrealized losses                                                                                                                                                                                        | 18cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                   | 75cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember                                                                                                                                   |
| Fixed Maturities | Corporate Securities                                                                                                                                                                        |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 261us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                        | 572us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                        |
| Less than 12 months unrealized losses                                                                                                                                                                          | 8cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                            | 20cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                           |
| 12 months or more fair value                                                                                                                                                                                   | 90us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                         | 43us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                         |
| 12 months or more unrealized losses                                                                                                                                                                            | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                            | 2cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                            |
| Total fair value                                                                                                                                                                                               | 351us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                                            | 615us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                                            |
| Total unrealized losses                                                                                                                                                                                        | 11cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                                           | 22cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CorporateBondSecuritiesMember                                           |
| Fixed Maturities | States, Municipalities and Political Subdivisions                                                                                                                                           |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 17us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                | 490us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember               |
| Less than 12 months unrealized losses                                                                                                                                                                          | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                   | 18cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                  |
| 12 months or more fair value                                                                                                                                                                                   | 135us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember               | 42us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                |
| 12 months or more unrealized losses                                                                                                                                                                            | 2cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                   | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                   |
| Total fair value                                                                                                                                                                                               | 152us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                   | 532us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                   |
| Total unrealized losses                                                                                                                                                                                        | 2cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                   | 21cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USStatesAndPoliticalSubdivisionsMember                                  |
| Fixed Maturities | Commercial Mortgage Backed Securities                                                                                                                                                       |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 3us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember               | 125us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember             |
| Less than 12 months unrealized losses                                                                                                                                                                          | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                 | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                 |
| 12 months or more fair value                                                                                                                                                                                   | 23us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember              | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember               |
| 12 months or more unrealized losses                                                                                                                                                                            | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                 | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                 |
| Total fair value                                                                                                                                                                                               | 26us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                  | 125us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                 |
| Total unrealized losses                                                                                                                                                                                        | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                 | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommercialMortgageBackedSecuritiesMember                                 |
| Fixed Maturities | Government-Sponsored Enterprises                                                                                                                                                            |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 11us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember  | 199us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember |
| Less than 12 months unrealized losses                                                                                                                                                                          | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember     | 27cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember    |
| 12 months or more fair value                                                                                                                                                                                   | 181us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember   |
| 12 months or more unrealized losses                                                                                                                                                                            | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember     | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember     |
| Total fair value                                                                                                                                                                                               | 192us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember                     | 200us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember                     |
| Total unrealized losses                                                                                                                                                                                        | 5cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember                     | 27cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember                    |
| Fixed Maturities | Foreign Government                                                                                                                                                                          |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                  | 10us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                 |
| Less than 12 months unrealized losses                                                                                                                                                                          |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                    |
| 12 months or more fair value                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                  | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                  |
| 12 months or more unrealized losses                                                                                                                                                                            |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                    |
| Total fair value                                                                                                                                                                                               |                                                                                                                                                                                                                                                                                  | 10us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                     |
| Total unrealized losses                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_ForeignGovernmentDebtSecuritiesMember                                    |
| Fixed Maturities | United States Government                                                                                                                                                                    |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 |                                                                                                                                                                                                                                                                                  | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember               |
| Less than 12 months unrealized losses                                                                                                                                                                          |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember                 |
| 12 months or more fair value                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                  | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember               |
| 12 months or more unrealized losses                                                                                                                                                                            |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember                 |
| Total fair value                                                                                                                                                                                               |                                                                                                                                                                                                                                                                                  | 1us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember                                   |
| Total unrealized losses                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_DebtSecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_USGovernmentAgenciesDebtSecuritiesMember                                 |
| Equity Securities                                                                                                                                                                                              |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 101us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                              | 119us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                              |
| Less than 12 months unrealized losses                                                                                                                                                                          | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                  | 4cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                  |
| 12 months or more fair value                                                                                                                                                                                   | 17us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                               | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                |
| 12 months or more unrealized losses                                                                                                                                                                            | 1cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                  | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                  |
| Total fair value                                                                                                                                                                                               | 118us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                                  | 119us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                                  |
| Total unrealized losses                                                                                                                                                                                        | 4cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                                  | 4cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember                                                                                                                                  |
| Equity Securities | Common Equities                                                                                                                                                                            |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 85us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                   | 77us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                   |
| Less than 12 months unrealized losses                                                                                                                                                                          | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                      | 1cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                      |
| 12 months or more fair value                                                                                                                                                                                   | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                    | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                    |
| 12 months or more unrealized losses                                                                                                                                                                            | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                      | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                      |
| Total fair value                                                                                                                                                                                               | 85us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                                       | 77us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                                       |
| Total unrealized losses                                                                                                                                                                                        | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                                      | 1cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_CommonStockMember                                                      |
| Equity Securities | Nonredeemable Preferred Equities                                                                                                                                                           |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| **Investments, Unrealized Loss Position**                                                                                                                                                                      |                                                                                                                                                                                                                                                                                  |                                                                                                                                                                                                                                                                                  |
| Less than 12 months fair value                                                                                                                                                                                 | 16us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                | 42us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                |
| Less than 12 months unrealized losses                                                                                                                                                                          | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                   | 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                   |
| 12 months or more fair value                                                                                                                                                                                   | 17us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                | 0us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                 |
| 12 months or more unrealized losses                                                                                                                                                                            | 1cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                   | 0cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                   |
| Total fair value                                                                                                                                                                                               | 33us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                    | 42us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                    |
| Total unrealized losses                                                                                                                                                                                        | $ 1cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                 | $ 3cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3/ invest_InvestmentSecuritiesClassAxis= us-gaap_EquitySecuritiesMember/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis= us-gaap_PreferredStockMember                                                 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.
+ References
No definition available.
+ Details**Name:**cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPosition12MonthsorLongerAggregateLoss3**Namespace Prefix:**cinf_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrealized loss on securities classified as available-for-sale.
+ References
No definition available.
+ Details**Name:**cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionAggregateLoss3**Namespace Prefix:**cinf_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.
+ References
No definition available.
+ Details**Name:**cinf_AvailableforsaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLoss3**Namespace Prefix:**cinf_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                        |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
+ Details**Name:**us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                           |
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