XML 118 R104.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Employee Retirement Benefits (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2008
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Minimum participant age to elect |  |  |  | 40 years
Employer discretionary contribution amount | $ 26 | $ 24 | $ 22 |
Requisite service period | 3 years |  |  |
Actual percentage return on plan assets | 11.80% | (8.90%) |  |
Pension plan assets at fair value | $ 317 | $ 332 | 397 |
Maximum |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Matching contribution to defined contribution plan | 6.00% |  |  |
Pension Plan |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Percentage of increase decrease in benefit obligations discount rate | 0.30% |  |  |
Change In Net Benefit Cost Discount Rate Assumption | 2.37% |  |  |
Pension Plan | Maximum |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Cash dividends paid (less than $1 million) | $ 1 | 1 |  |
Supplemental Employee Retirement Plan |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Accrued employee benefit | $ 11 | 8 |  |
Percentage of increase decrease in benefit obligations discount rate | 0.31% |  |  |
Change In Net Benefit Cost Discount Rate Assumption | 2.52% |  |  |
Expected contribution by employer during 2023 | $ 7 |  |  |
Top Hat Savings Plan - Mutual Funds and Common Equities |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
CFC Top Hat Savings Plan | 67 | 57 |  |
Top Hat |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
CFC Top Hat Savings Plan | 67 | 57 |  |
Top Hat | Top Hat Savings Plan - Mutual Funds and Common Equities | Maximum |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Employer discretionary contribution amount | $ 1 | $ 1 | $ 1 |
Employer Common Stock |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Pension plan assets, shares | 100,610 | 100,610 |  |
Pension plan assets, fair value | $ 10 | $ 10 |  |
Employer Common Stock | Sale of stock |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Pension plan assets, shares |  | 101,727 |  |
Equity Securities |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 90.00% |  |  |
Pension plan assets at fair value | $ 269 | $ 245 |  |
Equity Securities | Information Technology Sector |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 29.00% |  |  |
Equity Securities | Financial Services Sector |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 19.00% |  |  |
Equity Securities | Industrial Sector |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 16.00% |  |  |
Equity Securities | Healthcare Sector |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 13.00% |  |  |
Equity Securities | All Remaining Sectors |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 10.00% |  |  |
Fixed Maturities |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Pension plan assets at fair value | $ 32 | 44 |  |
Fixed Maturities | United States Government |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 7.00% |  |  |
Pension plan assets at fair value | $ 22 | 31 |  |
Fixed Maturities | States, Municipalities and Political Subdivisions |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 2.00% |  |  |
Pension plan assets at fair value | $ 6 | 6 |  |
Fixed Maturities | Domestic Corporate Debt Securities |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Allocation percentage of investments | 1.00% |  |  |
Pension plan assets at fair value | $ 4 | 7 |  |
Cash and Cash Equivalents |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans |  |  |  |
Pension plan assets at fair value | $ 16 | $ 43 |  |

X
- Definition Change in discount rate assumption. + References No definition available. + Details
Name: | cinf_ChangeInDiscountRateAssumption
Namespace Prefix: | cinf_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Change In Net Benefit Cost Discount Rate Assumption + References No definition available. + Details
Name: | cinf_ChangeInNetBenefitCostDiscountRateAssumption
Namespace Prefix: | cinf_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined Benefit Plan, Actual Percentage Return On Plan Assets + References No definition available. + Details
Name: | cinf_DefinedBenefitPlanActualPercentageReturnOnPlanAssets
Namespace Prefix: | cinf_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Age at which participants could elect to remain in the defined benefit plan as of August 31, 2008. + References No definition available. + Details
Name: | cinf_DefinedBenefitPlanQualifyingAge
Namespace Prefix: | cinf_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Defined Contribution Plan, Requisite Service Period + References No definition available. + Details
Name: | cinf_DefinedContributionPlanRequisiteServicePeriod
Namespace Prefix: | cinf_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
Name: | us-gaap_AccruedEmployeeBenefitsCurrentAndNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of employer security in which defined benefit plan asset is invested. Includes, but is not limited to, security issued or managed by related party of employer. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (n) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanAmountOfEmployerAndRelatedPartySecuritiesIncludedInPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of shares of employer stock in which defined benefit plan asset is invested. Includes, but is not limited to, stock issued or managed by related party of employer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (n) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanNumberOfSharesOfEquitySecuritiesIssuedByEmployerAndRelatedPartiesIncludedInPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlansAndOtherPostretirementBenefitPlansTableTextBlockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 505 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1 + Details
Name: | us-gaap_DividendsCommonStockCash
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Value of the other investment not readily marketable determined by management based upon fair value methods, including pricing of similar securities and valuation techniques, that was used to record the investment for financial reporting purposes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 940 -SubTopic 820 -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481753/940-820-50-1 + Details
Name: | us-gaap_OtherInvestmentNotReadilyMarketableFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_EquityFundsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=cinf_TopHatMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesCommonStockEmployerRelatedPartyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_EmployeeStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=cinf_InformationSystemsAndTechnologyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_FinancialServicesSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=cinf_IndustrialSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_HealthcareSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=cinf_AllRemainingSectorsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_DebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DomesticCorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_InvestmentTypeAxis=us-gaap_CashAndCashEquivalentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |