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v2.4.1.9

Investments (Details 2) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | $ 6,375,237 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis |  | $ 5,784,205 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis |
Unrealized Gains | 543,868 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains |  | 344,286 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains |
Unrealized Losses | 26,015 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss |  | 118,918 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss |
Fair Value | 6,893,090 us-gaap_AvailableForSaleSecuritiesDebtSecurities |  | 6,009,573 us-gaap_AvailableForSaleSecuritiesDebtSecurities |
OTTI in AOCI | 2,879 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest | [1] | 2,812 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest | [1]
Mortgage-backed securities [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 484,561 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2] | 555,574 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2]
Unrealized Gains | 52,555 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2] | 33,711 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2]
Unrealized Losses | 1,390 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2] | 19,560 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2]
Fair Value | 535,726 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2] | 569,725 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [2]
OTTI in AOCI | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [1],[2] | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember | [1],[2]
Other including U.S. Treasury Securities [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 512,596 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2] | 449,060 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2]
Unrealized Gains | 28,652 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2] | 9,865 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2]
Unrealized Losses | 3,049 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2] | 23,351 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2]
Fair Value | 538,199 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2] | 435,574 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [2]
OTTI in AOCI | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [1],[2] | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = hmn_OtherIncludingUsTreasurySecuritiesMember | [1],[2]
Municipal Bonds [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 1,462,717 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |  | 1,425,441 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |
Unrealized Gains | 189,533 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |  | 80,701 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |
Unrealized Losses | 4,428 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |  | 34,615 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |
Fair Value | 1,647,822 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |  | 1,471,527 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember |
OTTI in AOCI | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember | [1] | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MunicipalBondsMember | [1]
Foreign government bonds [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 52,552 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |  | 50,641 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |
Unrealized Gains | 6,984 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |  | 4,700 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |
Unrealized Losses | 0 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |  | 390 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |
Fair Value | 59,536 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |  | 54,951 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember |
OTTI in AOCI | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember | [1] | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtMember | [1]
Corporate Bonds [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 2,608,633 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |  | 2,457,727 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |
Unrealized Gains | 237,372 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |  | 188,832 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |
Unrealized Losses | 11,256 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |  | 32,150 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |
Fair Value | 2,834,749 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |  | 2,614,409 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember |
OTTI in AOCI | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember | [1] | 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember | [1]
Other Mortgage-backed Securities [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 1,254,178 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |  | 845,762 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |
Unrealized Gains | 28,772 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |  | 26,477 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |
Unrealized Losses | 5,892 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |  | 8,852 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |
Fair Value | 1,277,058 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |  | 863,387 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember |
OTTI in AOCI | 2,879 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember | [1] | 2,812 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_MortgageBackedSecuritiesOtherMember | [1]
Equity Securities [Member] |  |  |  |
Unrealized gains and losses on fixed maturities and equity securities |  |  |  |
Amortized Cost or Cost | 99,904 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |  | 84,754 us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
Unrealized Gains | 14,159 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |  | 10,723 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
Unrealized Losses | 3,408 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |  | 3,619 us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
Fair Value | 110,655 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |  | 91,858 us-gaap_AvailableForSaleSecuritiesDebtSecurities / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember |
OTTI in AOCI | $ 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember | [1] | $ 0 us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterest / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_EquitySecuritiesMember | [1]
[1] | Related to securities for which an unrealized loss was bifurcated to distinguish the credit related portion and the portion driven by other market factors. Represents the amount of other-than-temporary impairment losses in AOCI which was not included in earnings; amounts also include unrealized gains/(losses) on such impaired securities relating to changes in the fair value of those securities subsequent to the impairment measurement date.
[2] | Fair value includes securities issued by Federal National Mortgage Association (“FNMA”) of $302,222 and $336,193; Federal Home Loan Mortgage Corporation (“FHLMC”) of $432,432 and $427,172; and Government National Mortgage Association (“GNMA”) of $137,867 and $126,245 as of December 31, 2014 and 2013, respectively.

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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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