XML 59 R43.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Investments - Carrying Amount of Equity Method Limited Partnership Interests (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Schedule of Equity Method Investments |  |
Limited partnership interests | $ 997.5 | $ 712.8
Commercial mortgage loan funds |  |
Schedule of Equity Method Investments |  |
Limited partnership interests | 601.5 | 346.8
Private equity funds |  |
Schedule of Equity Method Investments |  |
Limited partnership interests | 73.4 | 74.0
Infrastructure equity funds |  |
Schedule of Equity Method Investments |  |
Limited partnership interests | 70.2 | 58.3
Infrastructure debt funds |  |
Schedule of Equity Method Investments |  |
Limited partnership interests | 67.4 | 62.4
Other funds |  |
Schedule of Equity Method Investments |  |
Limited partnership interests | $ 185.0 | $ 171.3

X
- Definition Amount of investment in equity method investee and investment in and advance to affiliate. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(18)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures
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_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

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

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

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

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