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Employee Benefit Plans - Additional Information (Detail) | 12 Months Ended |  | 12 Months Ended
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Dec. 31, 2014 USD ($) Rate | Dec. 31, 2014 Pension Benefits, U.S. Plans USD ($) | Dec. 31, 2013 Pension Benefits, U.S. Plans USD ($) | Dec. 31, 2012 Pension Benefits, U.S. Plans USD ($) | Dec. 31, 2014 Pension Benefits, Non U.S. Plans USD ($) | Dec. 31, 2014 Pension Benefits, Non U.S. Plans GBP (£) | Dec. 31, 2013 Pension Benefits, Non U.S. Plans USD ($) Rate | Dec. 31, 2013 Pension Benefits, Non U.S. Plans GBP (£) Rate | Dec. 31, 2012 Pension Benefits, Non U.S. Plans USD ($) Rate | Dec. 31, 2014 Other Postretirement Benefit Plans | Dec. 31, 2014 Other Postretirement Benefit Plans USD ($) | Dec. 31, 2013 Other Postretirement Benefit Plans USD ($) Rate | Dec. 31, 2012 Other Postretirement Benefit Plans USD ($) | Dec. 31, 2014 Equity Securites Pension Benefits, U.S. Plans Rate | Dec. 31, 2014 Fixed Maturity Securities Pension Benefits, U.S. Plans Rate | Dec. 31, 2014 Alternative Investments Pension Benefits, U.S. Plans Rate | Dec. 31, 2014 Diversified Growth Assets Pension Benefits, Non U.S. Plans Rate | Dec. 31, 2014 Interest Rate Contract Pension Benefits, Non U.S. Plans Rate | Dec. 31, 2014 Minimum | Dec. 31, 2014 Minimum Private Equity Funds Pension Benefits, U.S. Plans | Dec. 31, 2014 Maximum | Dec. 31, 2014 Maximum Private Equity Funds Pension Benefits, U.S. Plans | Dec. 31, 2012 Prior to Pension Amendments Pension Benefits, Non U.S. Plans | Dec. 31, 2013 After Pension Amendment Pension Benefits, U.S. Plans | Dec. 31, 2013 After Pension Amendment Pension Benefits, Non U.S. Plans | Dec. 31, 2013 Pre-Remeasurement Date Pension Benefits, U.S. Plans | Dec. 31, 2013 Pre-Remeasurement Date Pension Benefits, Non U.S. Plans | Dec. 31, 2013 Post-Remeasurement Date Pension Benefits, U.S. Plans | Dec. 31, 2013 Post-Remeasurement Date Pension Benefits, Non U.S. Plans | Dec. 31, 2014 U.S. Defined Contribution Plan USD ($) | Dec. 31, 2013 U.S. Defined Contribution Plan USD ($) Rate | Dec. 31, 2012 U.S. Defined Contribution Plan USD ($) | Dec. 31, 2014 Non U.S. Defined Contribution Plan USD ($) | Dec. 31, 2014 Non U.S. Defined Contribution Plan GBP (£) | Dec. 31, 2013 Non U.S. Defined Contribution Plan USD ($) | Dec. 31, 2012 Non U.S. Defined Contribution Plan USD ($)
Pension and Other Postretirement Benefits Disclosure |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension Plan Lump-sum Settlement Payment |  | $ 214,500,000 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | $ 0 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  | $ 0 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | $ 0 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  | $ 0 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | $ 0 us-gaap_DefinedBenefitPlanPurchasesSalesAndSettlements / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Pension Settlement Costs |  | 64,400,000 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 0 unm_EffectofPensionSettlementonNetPeriodicBenefitCosts / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount Rate Assumptions Used Calculating Benefit Obligation |  | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 5.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  | 3.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 3.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  | 4.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_PriortoorPostPensionAmendmentsAxis = unm_PriortoPensionAmendmentsMember | 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember / unm_PriortoorPostPensionAmendmentsAxis = unm_AfterPensionAmendmentMember | 4.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_PriortoorPostPensionAmendmentsAxis = unm_AfterPensionAmendmentMember |  |  |  |  |  |  |  |  |  |  |
Expected Long-term Return on Assets Assumptions Used Calculating Net Periodic Benefit Cost |  | 7.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 7.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  | 6.10%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 6.10%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  | 5.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.75%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  | 6.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_PriortoorPostPensionAmendmentsAxis = unm_PriortoPensionAmendmentsMember |  | 6.35%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_PriortoorPostPensionAmendmentsAxis = unm_AfterPensionAmendmentMember |  | 6.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PreRemeasurementDateMember |  | 6.35%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PostRemeasurementDateMember |  |  |  |  |  |  |
Decrease in Pension Liability Due to Remeasurement |  |  | 327,400,000 us-gaap_IncrementalEffectOnBalanceSheetLiabilityOrEquityLineItemChangeDueToAdditionalMinimumPensionLiabilityAMLAdjustmentPeriodIncreaseDecrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  |  |  | 2,300,000 us-gaap_IncrementalEffectOnBalanceSheetLiabilityOrEquityLineItemChangeDueToAdditionalMinimumPensionLiabilityAMLAdjustmentPeriodIncreaseDecrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 1,500,000 us-gaap_IncrementalEffectOnBalanceSheetLiabilityOrEquityLineItemChangeDueToAdditionalMinimumPensionLiabilityAMLAdjustmentPeriodIncreaseDecrease / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tax Impact of Curtailments |  |  | 114,600,000 unm_DefinedBenefitPlanCurtailmentsTaxImpact / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Recognized Net Gain (Loss) Due to Curtailments |  | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | (700,000)us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 3,700,000 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 2,300,000 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Curtailments |  | 0 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 126,800,000 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  | 0 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  | 3,700,000 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  | 0 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 4,200,000 us-gaap_DefinedBenefitPlanCurtailments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum Inflation Rate on Pensionable Earnings |  |  |  |  |  |  | 2.50%unm_MaximumInflationRateonPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 2.50%unm_MaximumInflationRateonPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 5.00%unm_MaximumInflationRateonPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Prior Service Credit Recognized in Other Comprehensive Income Before Tax |  |  |  |  |  |  |  |  |  |  |  |  | 5,000,000 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Average Remaining Life Expectancy of Plan Participants |  | 35 years |  |  | 34 years | 34 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Target Plan Asset Allocations |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 40.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_DebtSecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 25.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = unm_AlternativeInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 75.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = unm_DiversifiedGrowthAssetsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 25.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_InterestRateContractMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Private Equity Partnership Future Liquidation Term |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year | 5 years | 13 years | 8 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
Level 3 Transfers Into | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 |  |  |  |  |  |  |  |  |  | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Level 3 Transfers Out of |  |  |  |  |  |  |  |  |  |  | 0 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount Rate Assumptions Used Calculating Net Periodic Benefit Cost |  | 5.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  |  | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 4.40%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  | 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PreRemeasurementDateMember | 4.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PreRemeasurementDateMember | 5.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PostRemeasurementDateMember | 4.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember / unm_RelationtoRemeasurementDateAxis = unm_PostRemeasurementDateMember |  |  |  |  |  |  |
Interest Rate During Period |  |  |  |  |  |  |  |  |  | 5.46%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.46%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 5.58%us-gaap_DebtInstrumentInterestRateDuringPeriod / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Health Care Cost Trend Rate Assumed for Next Fiscal Year | 7.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear |  |  |  |  |  |  |  |  |  |  | 7.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ultimate Health Care Cost Trend Rate | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effect of One Percentage Point Increase on Service and Interest Cost Components | 100,000 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effect of One Percentage Point Decrease on Service and Interest Cost Components | (100,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation | 4,700,000 us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation | (3,400,000)us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Actuarial Loss to be Amortized from Accumulated Other Comprehensive Income Next Fiscal Year | 11,900,000 us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Discussion of Pension and Other Postretirement Benefits |  | We had no regulatory contribution requirements for our U.S. qualified defined benefit plan in 2014 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employer Contributions to Defined Benefit Plan |  | 5,300,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember | 54,700,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember |  | 2,300,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 1,400,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 4,000,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  | 12,000,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember | 11,700,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contributions Percent of Pensionable Earnings |  |  |  |  |  |  | 30.00%unm_PensionPlanContributionsPercentofPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 30.00%unm_PensionPlanContributionsPercentofPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember | 24.80%unm_PensionPlanContributionsPercentofPensionableEarnings / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_ForeignPensionPlansDefinedBenefitMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Matching Contribution Percent of Employees' Gross Pay |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember | 3.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember |  | 5.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | 5.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | 5.00%us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember |
Employer Discretionary Contribution Percentage of earnings |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 4.50%unm_DefinedContributionPlanEmployerDiscretionaryContributionPercentageofEarnings / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember |  |  | 6.00%unm_DefinedContributionPlanEmployerDiscretionaryContributionPercentageofEarnings / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | 6.00%unm_DefinedContributionPlanEmployerDiscretionaryContributionPercentageofEarnings / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | 5.00%unm_DefinedContributionPlanEmployerDiscretionaryContributionPercentageofEarnings / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember |
Employer Matching Contribution on amts over 3% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.50 unm_DefinedContributionPlanEmployerMatchingContributionOnAmtsOver3 / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember |  |  |  |  |
Employer Matching Contribution % for $0.50 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00%unm_DefinedContributionPlanEmployerMatchingContributionFor050 / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember |  |  |  |  |
Employer Matching Contribution for Every Pound on the First One Percent of Employee Contributions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 unm_DefinedContributionPlanEmployerMatchingContributionforEveryPoundontheFirstOnePercentofEmployeeContributions / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember |  |
Employee Contribution Percentage Received 2-for-1 Employer Match |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.00%unm_DefinedContributionPlanEmployeeContributionPercentageReceived2for1EmployerMatch / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | 1.00%unm_DefinedContributionPlanEmployeeContributionPercentageReceived2for1EmployerMatch / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember |  |
Cost Recognized |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 76,000,000 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember | $ 18,800,000.0 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember | $ 18,900,000.0 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_UnitedStatesPostretirementBenefitPlansOfUSEntityDefinedBenefitMember | $ 5,000,000 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember |  | $ 2,900,000.0 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember | $ 2,900,000.0 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedContributionPlanTypeAxis = us-gaap_ForeignPostretirementBenefitPlansDefinedBenefitMember

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- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (m) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Health Care Cost Trend Rate -URI http://asc.fasb.org/extlink&oid=6514820 + Details
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- Definition Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920 + Details
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- Definition The amount of net gain (loss) recognized in net periodic benefit cost as a result of an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Curtailment -URI http://asc.fasb.org/extlink&oid=6520938 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 + Details
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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920 + Details
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- Definition The ultimate trend rate for health care costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (l) -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Description of and general information regarding the types of plans utilized by the employer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2417-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2410-114920 + Details
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- Definition Changes in individual asset line items in the year-end statement of financial position that are incrementally affected by the additional minimum pension liability (AML) adjustment by the recognition provisions of FAS 158 in the year of initial application. + References No definition available. + Details
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