XML 135 R115.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Selected Operating Statement Data by Segment (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income | $ 1,967.9 us-gaap_PremiumsEarnedNet | $ 1,947.2 us-gaap_PremiumsEarnedNet | $ 1,943.6 us-gaap_PremiumsEarnedNet | $ 1,938.5 us-gaap_PremiumsEarnedNet | $ 1,890.7 us-gaap_PremiumsEarnedNet | $ 1,897.3 us-gaap_PremiumsEarnedNet | $ 1,905.8 us-gaap_PremiumsEarnedNet | $ 1,930.9 us-gaap_PremiumsEarnedNet | $ 7,797.2 us-gaap_PremiumsEarnedNet | $ 7,624.7 us-gaap_PremiumsEarnedNet | $ 7,716.1 us-gaap_PremiumsEarnedNet
Net Investment Income | 629.4 us-gaap_NetInvestmentIncome | 606.4 us-gaap_NetInvestmentIncome | 629.1 us-gaap_NetInvestmentIncome | 612.5 us-gaap_NetInvestmentIncome | 629.4 us-gaap_NetInvestmentIncome | 615.5 us-gaap_NetInvestmentIncome | 626.1 us-gaap_NetInvestmentIncome | 621.1 us-gaap_NetInvestmentIncome | 2,477.4 us-gaap_NetInvestmentIncome | 2,492.1 us-gaap_NetInvestmentIncome | 2,515.2 us-gaap_NetInvestmentIncome
Other Income |  |  |  |  |  |  |  |  | 219.0 us-gaap_OtherIncome | 230.2 us-gaap_OtherIncome | 227.9 us-gaap_OtherIncome
Interest and Debt Expense |  |  |  |  |  |  |  |  | 167.5 us-gaap_InterestAndDebtExpense | 149.4 us-gaap_InterestAndDebtExpense | 145.4 us-gaap_InterestAndDebtExpense
Operating Segments |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 7,797.2 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 7,624.7 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 7,716.1 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Net Investment Income |  |  |  |  |  |  |  |  | 2,477.4 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 2,492.1 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 2,515.2 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Other Income |  |  |  |  |  |  |  |  | 219.0 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 230.2 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 227.9 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Operating Revenue |  |  |  |  |  |  |  |  | 10,493.6 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 10,347.0 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 10,459.2 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | 1,292.5 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,241.8 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 1,239.7 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 154.3 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 149.4 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 145.4 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | 534.4 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 509.8 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember | 468.5 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember
Operating Segments | Unum U.S. |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 4,659.7 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 4,517.1 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 4,456.5 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Net Investment Income |  |  |  |  |  |  |  |  | 890.3 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 929.6 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 952.3 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Other Income |  |  |  |  |  |  |  |  | 122.1 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 128.3 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 124.6 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Operating Revenue |  |  |  |  |  |  |  |  | 5,672.1 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 5,575.0 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 5,533.4 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | 856.3 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 859.0 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 847.1 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 0.1 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 1.1 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | 314.2 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 292.5 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember | 255.6 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUsMember
Operating Segments | Unum U.K. |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 607.2 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 556.6 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 694.6 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Net Investment Income |  |  |  |  |  |  |  |  | 151.0 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 148.5 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 170.8 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Other Income |  |  |  |  |  |  |  |  | 0 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 0.1 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 0.1 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Operating Revenue |  |  |  |  |  |  |  |  | 758.2 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 705.2 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 865.5 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | 147.8 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 132.0 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 131.3 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | 19.2 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 22.5 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember | 27.2 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_UnumUkMember
Operating Segments | Colonial Life |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 1,273.7 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 1,232.2 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 1,194.5 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Net Investment Income |  |  |  |  |  |  |  |  | 146.7 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 145.4 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 138.6 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Other Income |  |  |  |  |  |  |  |  | 0.1 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 0.2 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 0.3 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Operating Revenue |  |  |  |  |  |  |  |  | 1,420.5 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 1,377.8 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 1,333.4 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | 300.2 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 284.9 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 274.3 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | 194.1 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 188.7 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember | 181.0 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ColonialLifeMember
Operating Segments | Closed Block |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 1,256.6 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 1,318.8 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 1,370.5 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Net Investment Income |  |  |  |  |  |  |  |  | 1,284.1 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 1,272.3 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 1,230.5 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Other Income |  |  |  |  |  |  |  |  | 91.8 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 93.9 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 100.1 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Operating Revenue |  |  |  |  |  |  |  |  | 2,632.5 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 2,685.0 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 2,701.1 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | 122.6 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 109.4 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 95.5 us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 7.3 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 8.4 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 10.4 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | 5.9 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 5.2 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember | 3.9 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = unm_ClosedBlockMember
Operating Segments | Corporate and Other Segment |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information |  |  |  |  |  |  |  |  |  |  |
Premium Income |  |  |  |  |  |  |  |  | 0 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 0 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 0 us-gaap_PremiumsEarnedNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Net Investment Income |  |  |  |  |  |  |  |  | 5.3 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (3.7)us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 23.0 us-gaap_NetInvestmentIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Other Income |  |  |  |  |  |  |  |  | 5.0 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 7.7 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 2.8 us-gaap_OtherIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Operating Revenue |  |  |  |  |  |  |  |  | 10.3 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 4.0 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 25.8 unm_OperatingRevenue / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Operating Income (Loss) |  |  |  |  |  |  |  |  | (134.4)us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (143.5)us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | (108.5)us-gaap_OperatingIncomeLoss / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Interest and Debt Expense |  |  |  |  |  |  |  |  | 147.0 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 140.9 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | 133.9 us-gaap_InterestAndDebtExpense / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember
Depreciation, Depletion and Amortization |  |  |  |  |  |  |  |  | $ 1.0 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | $ 0.9 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember | $ 0.8 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_CorporateAndOtherMember

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- Definition The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 + Details
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- Definition Interest and debt related expenses associated with nonoperating financing activities of the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 16 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.2) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 2 -Article 7 + Details
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