XML 68 R52.htm IDEA: XBRL DOCUMENT
v3.23.3

Fair Value of Financial Instruments - Quantitative Information about Level 3 Fair Value Measurements (Details) $ in Millions | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
--- | --- | --- | --- | --- | --- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | $ 4,961.6 |  | $ 5,185.0 |  |  |  |
Equity securities at fair value | 77.0 |  | 99.6 |  |  |  |
Net MRBs | (4.5) | $ (3.6) | 0.2 | $ 2.9 | $ 4.6 | $ 4.8 | $ 8.6
Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 4,961.6 |  | 5,185.0 |  |  |  |
Equity securities at fair value | 77.0 |  | 99.6 |  |  |  |
Financial Liabilities | 80.3 |  | 92.5 |  |  |  |
Mortgage-backed securities |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 590.5 |  | 570.4 |  |  |  |
Mortgage-backed securities | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 590.5 |  | 570.4 |  |  |  |
Municipal bonds |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,185.5 |  | 1,269.7 |  |  |  |
Municipal bonds | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,185.6 |  | 1,269.7 |  |  |  |
Corporate bonds |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,685.3 |  | 1,901.7 |  |  |  |
Corporate bonds | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,685.3 |  | 1,901.7 |  |  |  |
Other asset-backed securities |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,110.9 |  | 1,067.0 |  |  |  |
Other asset-backed securities | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 1,110.9 |  | 1,067.0 |  |  |  |
Level 3 | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 475.4 |  | 423.3 |  |  |  |
Equity securities at fair value | 2.2 |  | 2.0 |  |  |  |
Totals | 477.6 |  | 425.3 |  |  |  |
Financial Liabilities | 78.3 |  | 91.3 |  |  |  |
Derivatives embedded in fixed indexed annuity products | 82.8 |  |  |  |  |  |
Net MRBs | (4.5) |  |  |  |  |  |
Level 3 | Fair Value | Recurring | Internal |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 47.4 |  | 9.5 |  |  |  |
Equity securities at fair value | 0.0 |  | 0.0 |  |  |  |
Totals | 47.4 |  | 9.5 |  |  |  |
Financial Liabilities | 78.3 |  | 91.3 |  |  |  |
Level 3 | Fair Value | Recurring | External |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 428.0 |  | 413.8 |  |  |  |
Equity securities at fair value | 2.2 |  | 2.0 |  |  |  |
Totals | 430.2 |  | 415.8 |  |  |  |
Financial Liabilities | 0.0 |  | 0.0 |  |  |  |
Level 3 | Mortgage-backed securities | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 2.5 |  | 2.6 |  |  |  |
Level 3 | Mortgage-backed securities | Fair Value | Recurring | Internal |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 0.0 |  | 0.0 |  |  |  |
Level 3 | Mortgage-backed securities | Fair Value | Recurring | External |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 2.5 |  | 2.6 |  |  |  |
Level 3 | Municipal bonds | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 69.7 |  | 54.4 |  |  |  |
Level 3 | Municipal bonds | Fair Value | Recurring | Internal |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 0.0 |  | 0.0 |  |  |  |
Level 3 | Municipal bonds | Fair Value | Recurring | External |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 69.7 |  | 54.4 |  |  |  |
Level 3 | Corporate bonds | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 305.2 |  | 261.3 |  |  |  |
Level 3 | Corporate bonds | Fair Value | Recurring | Internal |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 47.4 |  | 9.5 |  |  |  |
Level 3 | Corporate bonds | Fair Value | Recurring | External |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 257.8 |  | 251.8 |  |  |  |
Level 3 | Other asset-backed securities | Fair Value | Recurring |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 98.0 |  | 105.0 |  |  |  |
Level 3 | Other asset-backed securities | Fair Value | Recurring | Internal |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | 0.0 |  | 0.0 |  |  |  |
Level 3 | Other asset-backed securities | Fair Value | Recurring | External |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Fair Value | $ 98.0 |  | $ 105.0 |  |  |  |
Minimum | Level 3 | discounted cash flow | option budget |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Derivatives embedded in fixed indexed annuity products, measurement input | 0.009 |  |  |  |  |  |
Minimum | Level 3 | Corporate bonds | discounted cash flow | yield |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Debt securities, measurement input | 0.083 |  |  |  |  |  |
Maximum | Level 3 | discounted cash flow | option budget |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Derivatives embedded in fixed indexed annuity products, measurement input | 0.038 |  |  |  |  |  |
Maximum | Level 3 | Corporate bonds | discounted cash flow | yield |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Debt securities, measurement input | 0.174 |  |  |  |  |  |
Weighted Average | Level 3 | discounted cash flow | lapse rate |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Derivatives embedded in fixed indexed annuity products, measurement input | 0.054 |  |  |  |  |  |
Net MRBs, measurement input | 0.059 |  |  |  |  |  |
Weighted Average | Level 3 | discounted cash flow | mortality multiplier |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Derivatives embedded in fixed indexed annuity products, measurement input | 0.678 |  |  |  |  |  |
Net MRBs, measurement input | 0.678 |  |  |  |  |  |
Weighted Average | Level 3 | discounted cash flow | non-performance adjustment |  |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |  |
Derivatives embedded in fixed indexed annuity products, measurement input | 0.050 |  |  |  |  |  |

X
- Definition Fair value of the liability as of the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported. + References No definition available. + Details
Name: | hmn_OtherPolicyholderFundsDerivativeInstrumentsFairValueDisclosure
Namespace Prefix: | hmn_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_AssetsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Value of input used to measure derivative liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_DerivativeLiabilityMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483467/210-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A + Details
Name: | us-gaap_EquitySecuritiesFvNi
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities. + References No definition available. + Details
Name: | us-gaap_FinancialLiabilitiesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, before effect of reinsurance and after accumulated increase (decrease) in instrument-specific credit risk, of contract or contract feature in long-duration contract issued by insurance entity that both protects contract holder from other-than-nominal capital market risk and exposes insurance entity to other-than-nominal capital market risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (h)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480016/944-40-65-2 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29G -Publisher FASB -URI https://asc.fasb.org//1943274/2147480046/944-40-55-29G Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 7B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480081/944-40-50-7B Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480112/944-40-45-3 + Details
Name: | us-gaap_MarketRiskBenefitAfterIncreaseDecreaseFromInstrumentSpecificCreditRisk
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Value of measurement input used to measure contract or contract feature in long-duration contract issued by insurance entity that both protects contract holder from other-than-nominal capital market risk and exposes insurance entity to other-than-nominal capital market risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_MarketRiskBenefitMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | hmn_FairValuePricingSourceAxis=hmn_InternalPricingSourceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | hmn_FairValuePricingSourceAxis=hmn_ExternalPricingSourceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=hmn_MeasurementInputOptionBudgetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=hmn_MeasurementInputYieldMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputLapseRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=us-gaap_MeasurementInputMortalityRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=hmn_MeasurementInputNonPerformanceAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |