$UNM
Unum Group Stock $unm

$unm Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000000551321000015 Filed on February 17, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020
Revenue	$4.274B	$2.996B	$13.16B
YoY Change	40.83%	1.23%	9.69%
Cost Of Revenue		$1.889B	$8.973B
YoY Change		0.91%	19.7%
Gross Profit		$1.108B	$4.189B
YoY Change		1.76%	-6.96%
Gross Profit Margin		36.97%	31.83%
Selling, General & Admin	$227.2M	$230.0M	$930.0M
YoY Change	2.62%	1.55%	3.56%
% of Gross Profit		20.76%	22.2%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$28.00M	$149.7M	$606.1M
YoY Change	1.82%	2.32%	-0.62%
% of Gross Profit		13.51%	14.47%
Operating Expenses	$4.103B	$2.624B	$11.97B
YoY Change	57.3%	1.34%	15.0%
Operating Profit		-$1.516B	-$7.785B
YoY Change		1.03%	31.74%
Interest Expense	-$45.60M	-$49.40M	-$188.0M
YoY Change	-2.15%	7.16%	6.21%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$124.7M	$299.6M	$924.7M
YoY Change	-66.96%	0.07%	-28.29%
Income Tax	-$10.70M	$68.50M	$171.0M
% Of Pretax Income	-8.58%	22.86%	18.49%
Net Earnings	$135.4M	$231.1M	$793.0M
YoY Change	-54.29%	-4.5%	-27.93%
Net Earnings / Revenue	3.17%	7.71%	6.02%
Basic Earnings Per Share	$0.66	$1.13	$3.89
Diluted Earnings Per Share	$0.66	$1.13	$3.89
COMMON SHARES
Basic Shares Outstanding	203.7M shares	203.8M shares	203.6M shares
Diluted Shares Outstanding		203.9M shares	203.8M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2020
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$197.0M	$103.8M	$197.0M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$498.0M	$508.8M	$581.0M
YoY Change	-6.76%	-10.47%	8.8%
Goodwill	$353.0M	$350.6M
YoY Change	0.37%	0.57%
Intangibles
YoY Change
Long-Term Investments	$52.68B	$58.36B	$52.68B
YoY Change	-5.47%	5.06%	-5.47%
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$70.63B	$69.62B	$70.63B
YoY Change	5.39%	3.97%	5.39%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$0.00	$0.00	$0.00
YoY Change	-100.0%	-100.0%	-100.0%
Total Short-Term Liabilities		$460.0M
YoY Change		-26.28%
LONG-TERM LIABILITIES
Long-Term Debt	$3.346B	$3.379B	$3.346B
YoY Change	14.31%	11.22%	14.31%
Other Long-Term Liabilities	$2.471B	$1.998B	$2.471B
YoY Change	31.37%	9.72%	31.37%
Total Long-Term Liabilities	$3.346B	$5.377B	$5.817B
YoY Change	14.31%	10.66%	20.99%
TOTAL LIABILITIES
Total Short-Term Liabilities		$460.0M
Total Long-Term Liabilities	$3.346B	$5.377B	$5.817B
Total Liabilities	$59.75B	$58.72B	$59.76B
YoY Change	4.74%	2.44%	4.75%
SHAREHOLDERS EQUITY
Retained Earnings	$11.27B	$11.19B
YoY Change	5.04%	6.68%
Common Stock	$2.407B	$2.402B
YoY Change	1.19%	1.23%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.180B	$3.180B
YoY Change	0.0%	3.25%
Treasury Stock Shares	102.9M shares	102.9M shares
Shareholders Equity	$10.87B	$10.89B	$10.87B
YoY Change
Total Liabilities & Shareholders Equity	$70.63B	$69.62B	$70.63B
YoY Change	5.39%	3.97%	5.39%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020
OPERATING ACTIVITIES
Net Income	$135.4M	$231.1M	$793.0M
YoY Change	-54.29%	-4.5%	-27.93%
Depreciation, Depletion And Amortization	$28.00M	$149.7M	$606.1M
YoY Change	1.82%	2.32%	-0.62%
Cash From Operating Activities	-$681.3M	$426.4M	$469.3M
YoY Change	-240.53%	35.75%	-70.79%
INVESTING ACTIVITIES
Capital Expenditures	-$19.60M	-$22.00M	$119.1M
YoY Change	-54.84%	-48.36%	-21.07%
Acquisitions			$0.00
YoY Change
Other Investing Activities	$842.0M	$22.60M	$0.00
YoY Change	-683.91%	-114.48%	-100.0%
Cash From Investing Activities	$822.4M	$600.0K	-$267.7M
YoY Change	-538.38%	-100.3%	-80.79%
FINANCING ACTIVITIES
Cash Dividend Paid			$231.9M
YoY Change			1.18%
Common Stock Issuance & Retirement, Net			-$4.400M
YoY Change			-101.12%
Debt Paid & Issued, Net			$80.00M
YoY Change			-83.78%
Cash From Financing Activities	-47.90M	-488.8M	-$88.70M
YoY Change	-83.49%	392.74%	-60.22%
NET CHANGE
Cash From Operating Activities	-681.3M	426.4M	$469.3M
Cash From Investing Activities	822.4M	600.0K	-$267.7M
Cash From Financing Activities	-47.90M	-488.8M	-$88.70M
Net Change In Cash	93.20M	-61.80M	$112.9M
YoY Change	1212.68%	-481.48%	-1240.4%
FREE CASH FLOW
Cash From Operating Activities	-$681.3M	$426.4M	$469.3M
Capital Expenditures	-$19.60M	-$22.00M	$119.1M
Free Cash Flow	-$661.7M	$448.4M	$350.2M
YoY Change	-225.27%	25.71%	-75.94%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-11294
CY2020	dei	Entity Registrant Name EntityRegistrantName	Unum Group
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	62-1598430
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	1 Fountain Square
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CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	TN
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CY2020	dei	Local Phone Number LocalPhoneNumber	294-1011
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2020	dei	Entity Shell Company EntityShellCompany	false
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CY2019	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance Tax Expense ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceTaxExpense	-511700000	USD
CY2018	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance Tax Expense ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceTaxExpense	371700000	USD
CY2020	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance And Net Of Tax Expense Benefit ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceAndNetOfTaxExpenseBenefit	-531200000	USD
CY2019	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance And Net Of Tax Expense Benefit ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceAndNetOfTaxExpenseBenefit	-1942600000	USD
CY2018	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance And Net Of Tax Expense Benefit ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceAndNetOfTaxExpenseBenefit	1411800000	USD
CY2020	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-23800000	USD
CY2019	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-17000000.0	USD
CY2018	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-8200000	USD
CY2020	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Net Of Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentNetOfTax	-90000000.0	USD
CY2019	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Net Of Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentNetOfTax	-62800000	USD
CY2018	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Net Of Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentNetOfTax	-31700000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	4300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	600000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	20300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	23600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-50700000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	34800000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	9300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-17000000.0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	45200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	37600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-60900000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	336900000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	851500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-924200000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1129900000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1951800000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-400800000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.14
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.09
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.98
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	10871000000.0	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	9965000000.0	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	8621800000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	793000000.0	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	1100300000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	523400000	USD
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-242900000	USD
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-37500000	USD
CY2018	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	4700000	USD
CY2020	us-gaap	Deferred Policy Acquisition Costs Period Increase Decrease DeferredPolicyAcquisitionCostsPeriodIncreaseDecrease	-29900000	USD
CY2019	us-gaap	Deferred Policy Acquisition Costs Period Increase Decrease DeferredPolicyAcquisitionCostsPeriodIncreaseDecrease	48700000	USD
CY2018	us-gaap	Deferred Policy Acquisition Costs Period Increase Decrease DeferredPolicyAcquisitionCostsPeriodIncreaseDecrease	102500000	USD
CY2020	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	1610000000.0	USD
CY2019	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	376100000	USD
CY2018	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	1193100000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-31300000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	248200000	USD
CY2018	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-39100000	USD
CY2020	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	160100000	USD
CY2019	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	51300000	USD
CY2018	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-10100000	USD
CY2020	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	120500000	USD
CY2019	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	237900000	USD
CY2018	us-gaap	Increase Decrease In Accrued Investment Income Receivable IncreaseDecreaseInAccruedInvestmentIncomeReceivable	211100000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	1199100000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	-23200000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	-39500000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	113600000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	110100000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	101400000	USD
CY2020	unm	Net Cash Paid In Relation To Reinsurance Agreement NetCashPaidInRelationToReinsuranceAgreement	-1084600000	USD
CY2019	unm	Net Cash Paid In Relation To Reinsurance Agreement NetCashPaidInRelationToReinsuranceAgreement	0	USD
CY2018	unm	Net Cash Paid In Relation To Reinsurance Agreement NetCashPaidInRelationToReinsuranceAgreement	0	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-83500000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-81500000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-46600000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	597500000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1741600000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1536500000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	990800000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	955200000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	642500000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2052400000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2401000000.0	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2815400000	USD
CY2020	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	237000000.0	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	363500000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Other Investments ProceedsFromSaleAndMaturityOfOtherInvestments	454000000.0	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	3169600000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	4022400000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	3861700000	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	440600000	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	568500000	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	623200000	USD
CY2020	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	133100000	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	267600000	USD
CY2018	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-200500000	USD
CY2020	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	314500000	USD
CY2019	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	-104100000	USD
CY2018	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	-268100000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	145400000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	119100000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	150900000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	144100000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-300000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-267700000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1393500000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-930100000	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-400000000.0	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	0	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-200000000.0	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	494100000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	841900000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	290700000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	80000000.0	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	493100000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	60000000.0	USD
CY2020	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	25900000	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	0	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4400000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	6100000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4600000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	400300000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	356200000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	231900000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	229200000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	215600000	USD
CY2020	unm	Cash Received Related To Active Life Volatility Cover Agreement Reinsurance Agreement CashReceivedRelatedToActiveLifeVolatilityCoverAgreementReinsuranceAgreement	62100000	USD
CY2019	unm	Cash Received Related To Active Life Volatility Cover Agreement Reinsurance Agreement CashReceivedRelatedToActiveLifeVolatilityCoverAgreementReinsuranceAgreement	0	USD
CY2018	unm	Cash Received Related To Active Life Volatility Cover Agreement Reinsurance Agreement CashReceivedRelatedToActiveLifeVolatilityCoverAgreementReinsuranceAgreement	0	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-65600000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-57500000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-53300000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-216900000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-358000000.0	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-589800000	USD
CY2020	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	112900000	USD
CY2019	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-9900000	USD
CY2018	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	16600000	USD
CY2019Q4	us-gaap	Cash Cash	84100000	USD
CY2018Q4	us-gaap	Cash Cash	94000000.0	USD
CY2017Q4	us-gaap	Cash Cash	77400000	USD
CY2020Q4	us-gaap	Cash Cash	197000000.0	USD
CY2019Q4	us-gaap	Cash Cash	84100000	USD
CY2018Q4	us-gaap	Cash Cash	94000000.0	USD
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	Integer
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Use of Estimates</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">: The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in the financial statements and accompanying notes. Such estimates and assumptions could change in the future as more information becomes known, which could impact the amounts reported and disclosed herein.</span>
CY2020Q4	unm	Policy Loans Cededto Reinsurers PolicyLoansCededtoReinsurers	3390600000	USD
CY2019Q4	unm	Policy Loans Cededto Reinsurers PolicyLoansCededtoReinsurers	3490600000	USD
CY2020Q1	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	23800000	USD
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	38800000	USD
CY2020Q1	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	543000000.0	USD
CY2020Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	525800000	USD
CY2020	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	15000000.0	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1239900000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1195300000	USD
CY2020Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	83800000	USD
CY2019Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	88700000	USD
CY2020Q4	us-gaap	Accumulated Amortization Of Other Deferred Costs AccumulatedAmortizationOfOtherDeferredCosts	153700000	USD
CY2019Q4	us-gaap	Accumulated Amortization Of Other Deferred Costs AccumulatedAmortizationOfOtherDeferredCosts	144100000	USD
CY2020	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	6100000	USD
CY2019	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	7100000	USD
CY2018	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	6400000	USD
CY2020	us-gaap	Revenue Recognition Sales Of Services RevenueRecognitionSalesOfServices	Fees from our leave management services and administrative-services only (ASO) business are reported as other income when services are rendered.
CY2020Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	813000000.0	USD
CY2020Q4	us-gaap	Deferred Revenue And Credits DeferredRevenueAndCredits	5600000	USD
CY2019Q4	us-gaap	Deferred Revenue And Credits DeferredRevenueAndCredits	8500000	USD
CY2020Q1	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1800000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	11700000	USD
CY2020	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	9900000	USD
CY2020	unm	Premium Tax Expense PremiumTaxExpense	175500000	USD
CY2019	unm	Premium Tax Expense PremiumTaxExpense	170100000	USD
CY2018	unm	Premium Tax Expense PremiumTaxExpense	155800000	USD
CY2020Q4	unm	Assets Participation Fund Account AssetsParticipationFundAccount	319800000	USD
CY2019Q4	unm	Assets Participation Fund Account AssetsParticipationFundAccount	311200000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	44137300000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	19800000	USD
CY2020Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	28300000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	44932900000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	99500000	USD
CY2020Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	99500000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	47443700000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	27500000	USD
CY2019Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	32600000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	48120500000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	57400000	USD
CY2019Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	57400000	USD
CY2020Q4	unm	Policy Loans Cededto Reinsurers PolicyLoansCededtoReinsurers	3390600000	USD
CY2019Q4	unm	Policy Loans Cededto Reinsurers PolicyLoansCededtoReinsurers	3490600000	USD
CY2020Q4	unm	Debt Securities Available For Sale Amortized Cost Maturity Allocated And Single Maturity Date Year One Net DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateYearOneNet	881800000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Within One Year Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearUnrealizedGainPositionGrossGain	19500000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Within One Year Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearUnrealizedLossPositionGrossLoss	2900000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	0	USD
CY2020Q4	unm	Debt Securities Available For Sale Amortized Cost Maturity Allocated And Single Maturity Date After Year One Through Five Net DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFiveNet	6162600000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After One Through Five Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsUnrealizedGainPositionGrossGain	589900000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After One Through Five Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsUnrealizedLossPositionGrossLoss	22900000	USD
CY2020Q4	unm	Debt Securities Available For Sale Amortized Cost Maturity Allocated And Single Maturity Date After Year5 Through10 Net DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateAfterYear5Through10Net	10886900000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After Five Through Ten Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsUnrealizedGainPositionGrossGain	1914800000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After Five Through Ten Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsUnrealizedLossPositionGrossLoss	10700000	USD
CY2020Q4	unm	Debt Securities Available For Sale Amortized Cost Maturity Allocated And Single Maturity Date After Year10 Net DebtSecuritiesAvailableForSaleAmortizedCostMaturityAllocatedAndSingleMaturityDateAfterYear10Net	17588500000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After Ten Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsUnrealizedGainPositionGrossGain	5041300000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities After Ten Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsUnrealizedLossPositionGrossLoss	19200000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Amortized Cost Gross Subtotal Net AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostGrossSubtotalNet	35519800000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Unrealized Gain Position Gross Gain Gross Subtotal AvailableForSaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossGainGrossSubtotal	7565500000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Unrealized Gain Position Gross Loss Gross Subtotal AvailableForSaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossLossGrossSubtotal	55700000	USD
CY2020Q4	unm	Debt Securities Available For Sale Maturity Without Single Maturity Date Amortized Cost Net DebtSecuritiesAvailableForSaleMaturityWithoutSingleMaturityDateAmortizedCostNet	1019900000	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Without Single Maturity Date Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateUnrealizedGainPositionGrossGain	88000000.0	USD
CY2020Q4	unm	Available For Sale Securities Debt Maturities Without Single Maturity Date Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateUnrealizedLossPositionGrossLoss	200000	USD
CY2020Q4	unm	Debt Securities Available For Sale Amortized Cost Net Of Allowance For Credit Losses DebtSecuritiesAvailableForSaleAmortizedCostNetOfAllowanceForCreditLosses	36539700000	USD
CY2020Q4	unm	Availableforsale Securities Debt Maturities Unrealized Gain Position Gross Gain AvailableforsaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossGain	7653500000	USD
CY2020Q4	unm	Available For Sale Securities Unrealized Loss Position Gross Loss Subtotal AvailableForSaleSecuritiesUnrealizedLossPositionGrossLossSubtotal	55900000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	821500000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Within One Year Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearUnrealizedGainPositionGrossGain	14500000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Within One Year Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearUnrealizedLossPositionGrossLoss	200000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	6286200000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After One Through Five Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsUnrealizedGainPositionGrossGain	456500000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After One Through Five Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsUnrealizedLossPositionGrossLoss	41700000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	13570800000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After Five Through Ten Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsUnrealizedGainPositionGrossGain	1688300000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After Five Through Ten Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsUnrealizedLossPositionGrossLoss	14600000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	19023000000.0	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After Ten Years Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsUnrealizedGainPositionGrossGain	4195000000.0	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities After Ten Years Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsUnrealizedLossPositionGrossLoss	34300000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Amortized Cost Gross Subtotal AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostGrossSubtotal	39701500000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Unrealized Gain Position Gross Gain Gross Subtotal AvailableForSaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossGainGrossSubtotal	6354300000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Unrealized Gain Position Gross Loss Gross Subtotal AvailableForSaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossLossGrossSubtotal	90800000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	1377800000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Without Single Maturity Date Unrealized Gain Position Gross Gain AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateUnrealizedGainPositionGrossGain	101300000	USD
CY2019Q4	unm	Available For Sale Securities Debt Maturities Without Single Maturity Date Unrealized Loss Position Gross Loss AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateUnrealizedLossPositionGrossLoss	400000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	41079300000	USD
CY2019Q4	unm	Availableforsale Securities Debt Maturities Unrealized Gain Position Gross Gain AvailableforsaleSecuritiesDebtMaturitiesUnrealizedGainPositionGrossGain	6455600000	USD
CY2019Q4	unm	Available For Sale Securities Unrealized Loss Position Gross Loss Subtotal AvailableForSaleSecuritiesUnrealizedLossPositionGrossLossSubtotal	91200000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	44137300000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	7653500000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	55900000	USD
CY2020Q4	unm	Fixed Maturity Securities In Unrealized Loss Position Percent Of Total FixedMaturitySecuritiesInUnrealizedLossPositionPercentOfTotal	1.000
CY2020Q4	unm	Commitment To Fund Private Placement Fixed Maturity Securities CommitmentToFundPrivatePlacementFixedMaturitySecurities	21000000.0	USD
CY2020	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	33200000	USD
CY2019	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	37800000	USD
CY2018	us-gaap	Affordable Housing Tax Credits And Other Tax Benefits Amount AffordableHousingTaxCreditsAndOtherTaxBenefitsAmount	41400000	USD
CY2020	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	21900000	USD
CY2019	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	25200000	USD
CY2018	us-gaap	Amortization Method Qualified Affordable Housing Project Investments Amortization AmortizationMethodQualifiedAffordableHousingProjectInvestmentsAmortization	28100000	USD
CY2020	unm	Tax Benefitsfrom Low Income Housing Investments TaxBenefitsfromLowIncomeHousingInvestments	11300000	USD
CY2019	unm	Tax Benefitsfrom Low Income Housing Investments TaxBenefitsfromLowIncomeHousingInvestments	12600000	USD
CY2018	unm	Tax Benefitsfrom Low Income Housing Investments TaxBenefitsfromLowIncomeHousingInvestments	13300000	USD
CY2020Q4	us-gaap	Qualified Affordable Housing Project Investments Commitment QualifiedAffordableHousingProjectInvestmentsCommitment	900000	USD
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2020Q4	unm	Percentage Of Loan Portfolio PercentageOfLoanPortfolio	1.000
CY2019Q4	unm	Percentage Of Loan Portfolio PercentageOfLoanPortfolio	1.000
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2020Q4	unm	Percentage Of Loan Portfolio PercentageOfLoanPortfolio	1.000
CY2019Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2397000000.0	USD
CY2019Q4	unm	Percentage Of Loan Portfolio PercentageOfLoanPortfolio	1.000
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2019Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2397000000.0	USD
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2019Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2397000000.0	USD
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2020Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	2432100000	USD
CY2020	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
CY2018	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
CY2019	us-gaap	Gains Losses On Sales Of Other Real Estate GainsLossesOnSalesOfOtherRealEstate	0	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	600000	USD
CY2018	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	2300000	USD
CY2020Q4	unm	Committments To Fund Commercial Mortgage Loans CommittmentsToFundCommercialMortgageLoans	11400000	USD
CY2020Q4	us-gaap	Real Estate Investment Property Net RealEstateInvestmentPropertyNet	106300000	USD
CY2019Q4	us-gaap	Real Estate Investment Property Net RealEstateInvestmentPropertyNet	90500000	USD
CY2020Q4	us-gaap	Real Estate Investment Property Accumulated Depreciation RealEstateInvestmentPropertyAccumulatedDepreciation	97700000	USD
CY2019Q4	us-gaap	Real Estate Investment Property Accumulated Depreciation RealEstateInvestmentPropertyAccumulatedDepreciation	49800000	USD
CY2020	us-gaap	Repurchase Agreements Maturities RepurchaseAgreementsMaturities	30
CY2020Q4	unm	Collateral Requirements Minimum Percentage Collateral To Fair Value Of Securities Loaned Or Purchased Under Repurchase Agreements CollateralRequirementsMinimumPercentageCollateralToFairValueOfSecuritiesLoanedOrPurchasedUnderRepurchaseAgreements	1.02
CY2020Q4	unm	Collateral Requirements Minimum Percentage Collateral To Fair Value Of Securities Loaned Or Purchased Under Repurchase Agreements CollateralRequirementsMinimumPercentageCollateralToFairValueOfSecuritiesLoanedOrPurchasedUnderRepurchaseAgreements	1.02
CY2020Q4	us-gaap	Securities Borrowed Gross SecuritiesBorrowedGross	96600000	USD
CY2019Q4	us-gaap	Securities Borrowed Gross SecuritiesBorrowedGross	176400000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	0	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	28200000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	18500000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	312200000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances Branch Of Fhlb Bank Amount Of Advances By Branch FederalHomeLoanBankAdvancesBranchOfFHLBBankAmountOfAdvancesByBranch	0	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged1 FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1	2016500000	USD
CY2019Q4	us-gaap	Federal Home Loan Bank Advances General Debt Obligations Disclosures Collateral Pledged1 FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1	346500000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	19800000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	0	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	19800000	USD
CY2020Q4	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	10100000	USD
CY2020Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	8700000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	1000000.0	USD
CY2020Q4	us-gaap	Securities Borrowed Gross SecuritiesBorrowedGross	96600000	USD
CY2020Q4	us-gaap	Securities Borrowed Liability SecuritiesBorrowedLiability	0	USD
CY2020Q4	us-gaap	Securities Borrowed SecuritiesBorrowed	96600000	USD
CY2020Q4	us-gaap	Securities Borrowed Collateral Obligation To Return Securities SecuritiesBorrowedCollateralObligationToReturnSecurities	79000000.0	USD
CY2020Q4	us-gaap	Securities Borrowed Collateral Obligation To Return Cash SecuritiesBorrowedCollateralObligationToReturnCash	17600000	USD
CY2020Q4	us-gaap	Securities Borrowed Amount Offset Against Collateral SecuritiesBorrowedAmountOffsetAgainstCollateral	0	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Gross DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedGross	116400000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Liability DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedLiability	0	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowed	116400000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Securities DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnSecurities	89100000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Cash DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnCash	26300000	USD
CY2020Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Amount Offset Against Collateral DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedAmountOffsetAgainstCollateral	1000000.0	USD
CY2020Q4	us-gaap	Securities Loaned Gross SecuritiesLoanedGross	17600000	USD
CY2020Q4	us-gaap	Securities Loaned Asset SecuritiesLoanedAsset	0	USD
CY2020Q4	us-gaap	Securities Loaned SecuritiesLoaned	17600000	USD
CY2020Q4	us-gaap	Securities Loaned Collateral Right To Reclaim Securities SecuritiesLoanedCollateralRightToReclaimSecurities	17600000	USD
CY2020Q4	us-gaap	Securities Loaned Collateral Right To Reclaim Cash SecuritiesLoanedCollateralRightToReclaimCash	0	USD
CY2020Q4	us-gaap	Securities Loaned Amount Offset Against Collateral SecuritiesLoanedAmountOffsetAgainstCollateral	0	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Gross DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedGross	77300000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Asset DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAsset	0	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoaned	77300000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Securities DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimSecurities	76600000	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Collateral Right To Reclaim Cash DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedCollateralRightToReclaimCash	0	USD
CY2020Q4	us-gaap	Derivative Liability Securities Sold Under Agreements To Resell Securities Loaned Amount Offset Against Collateral DerivativeLiabilitySecuritiesSoldUnderAgreementsToResellSecuritiesLoanedAmountOffsetAgainstCollateral	700000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	27500000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	0	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	27500000	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Securities DerivativeCollateralObligationToReturnSecurities	4000000.0	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	23500000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral	0	USD
CY2019Q4	us-gaap	Securities Borrowed Gross SecuritiesBorrowedGross	176400000	USD
CY2019Q4	us-gaap	Securities Borrowed Liability SecuritiesBorrowedLiability	0	USD
CY2019Q4	us-gaap	Securities Borrowed SecuritiesBorrowed	176400000	USD
CY2019Q4	us-gaap	Securities Borrowed Collateral Obligation To Return Securities SecuritiesBorrowedCollateralObligationToReturnSecurities	176400000	USD
CY2019Q4	us-gaap	Securities Borrowed Collateral Obligation To Return Cash SecuritiesBorrowedCollateralObligationToReturnCash	0	USD
CY2019Q4	us-gaap	Securities Borrowed Amount Offset Against Collateral SecuritiesBorrowedAmountOffsetAgainstCollateral	0	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Gross DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedGross	203900000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Liability DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedLiability	0	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowed	203900000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Securities DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnSecurities	180400000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Collateral Obligation To Return Cash DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedCollateralObligationToReturnCash	23500000	USD
CY2019Q4	us-gaap	Derivative Asset Securities Purchased Under Agreements To Resell Securities Borrowed Amount Offset Against Collateral DerivativeAssetSecuritiesPurchasedUnderAgreementsToResellSecuritiesBorrowedAmountOffsetAgainstCollateral	0	USD
CY2020	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	2403700000	USD
CY2019	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	2480200000	USD
CY2018	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	2502400000	USD
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	30600000	USD
CY2019	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	32100000	USD
CY2018	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	35200000	USD
CY2020	unm	Investment Income On Pfa Assets InvestmentIncomeOnPfaAssets	12400000	USD
CY2019	unm	Investment Income On Pfa Assets InvestmentIncomeOnPfaAssets	12800000	USD
CY2018	unm	Investment Income On Pfa Assets InvestmentIncomeOnPfaAssets	13500000	USD
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	2360700000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	2435300000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	2453700000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	1332800000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	22900000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	9700000	USD
CY2020	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	20300000	USD
CY2019	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	32600000	USD
CY2018	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	15200000	USD
CY2020	unm	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease And Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecreaseAndOtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	53600000	USD
CY2019	unm	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease And Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecreaseAndOtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	25300000	USD
CY2018	unm	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease And Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecreaseAndOtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	17500000	USD
CY2020	unm	Other Investments Gross Realized Gains OtherInvestmentsGrossRealizedGains	1900000	USD
CY2019	unm	Other Investments Gross Realized Gains OtherInvestmentsGrossRealizedGains	4600000	USD
CY2018	unm	Other Investments Gross Realized Gains OtherInvestmentsGrossRealizedGains	500000	USD
CY2020	unm	Other Investments Gross Realized Losses OtherInvestmentsGrossRealizedLosses	300000	USD
CY2019	unm	Other Investments Gross Realized Losses OtherInvestmentsGrossRealizedLosses	300000	USD
CY2018	unm	Other Investments Gross Realized Losses OtherInvestmentsGrossRealizedLosses	0	USD
CY2020	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	36600000	USD
CY2019	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0	USD
CY2018	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	1400000	USD
CY2020	unm	Financing Receivables Allowance For Credit Losses Period Increase Decrease Commercial Mortgage Loans And Unfunded Loan Commitments FinancingReceivablesAllowanceForCreditLossesPeriodIncreaseDecreaseCommercialMortgageLoansAndUnfundedLoanCommitments	4600000	USD
CY2019	unm	Financing Receivables Allowance For Credit Losses Period Increase Decrease Commercial Mortgage Loans And Unfunded Loan Commitments FinancingReceivablesAllowanceForCreditLossesPeriodIncreaseDecreaseCommercialMortgageLoansAndUnfundedLoanCommitments	0	USD
CY2018	unm	Financing Receivables Allowance For Credit Losses Period Increase Decrease Commercial Mortgage Loans And Unfunded Loan Commitments FinancingReceivablesAllowanceForCreditLossesPeriodIncreaseDecreaseCommercialMortgageLoansAndUnfundedLoanCommitments	0	USD
CY2020	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	-17000000.0	USD
CY2019	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	8300000	USD
CY2018	us-gaap	Embedded Derivative Gain Loss On Embedded Derivative Net EmbeddedDerivativeGainLossOnEmbeddedDerivativeNet	-15200000	USD
CY2020	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-2500000	USD
CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-100000	USD
CY2018	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	300000	USD
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-700000	USD
CY2019	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-700000	USD
CY2018	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-700000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	1199100000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	-23200000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	-39500000	USD
CY2020Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	59700000	USD
CY2019Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	34600000	USD
CY2017Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	904500000	USD
CY2018	unm	Notional Amount Of Derivatives Additions NotionalAmountOfDerivativesAdditions	136500000	USD
CY2018	unm	Notional Amount Of Derivatives Terminations NotionalAmountOfDerivativesTerminations	241800000	USD
CY2018Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	799200000	USD
CY2019	unm	Notional Amount Of Derivatives Additions NotionalAmountOfDerivativesAdditions	553700000	USD
CY2019	unm	Notional Amount Of Derivatives Terminations NotionalAmountOfDerivativesTerminations	471500000	USD
CY2019	unm	Notional Amount Of Derivatives Foreign Currency NotionalAmountOfDerivativesForeignCurrency	0	USD
CY2019Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	881400000	USD
CY2020	unm	Notional Amount Of Derivatives Additions NotionalAmountOfDerivativesAdditions	120000000.0	USD
CY2020	unm	Notional Amount Of Derivatives Terminations NotionalAmountOfDerivativesTerminations	257300000	USD
CY2020	unm	Notional Amount Of Derivatives Foreign Currency NotionalAmountOfDerivativesForeignCurrency	300000	USD
CY2020Q4	us-gaap	Derivative Notional Amount DerivativeNotionalAmount	744400000	USD
CY2020	us-gaap	Interest Rate Cash Flow Hedge Gain Loss Reclassified To Earnings Net InterestRateCashFlowHedgeGainLossReclassifiedToEarningsNet	30700000	USD
CY2020	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	60300000	USD
CY2020	us-gaap	Gain Loss From Components Excluded From Assessment Of Fair Value Hedge Effectiveness Net GainLossFromComponentsExcludedFromAssessmentOfFairValueHedgeEffectivenessNet	-1800000	USD
CY2019	us-gaap	Gain Loss From Components Excluded From Assessment Of Fair Value Hedge Effectiveness Net GainLossFromComponentsExcludedFromAssessmentOfFairValueHedgeEffectivenessNet	2000000.0	USD
CY2018	us-gaap	Gain Loss From Components Excluded From Assessment Of Fair Value Hedge Effectiveness Net GainLossFromComponentsExcludedFromAssessmentOfFairValueHedgeEffectivenessNet	2500000	USD
CY2019	us-gaap	Gain Loss From Hedged Firm Commitment Not Qualifying As Fair Value Hedge Net GainLossFromHedgedFirmCommitmentNotQualifyingAsFairValueHedgeNet	0	USD
CY2020	us-gaap	Gain Loss From Hedged Firm Commitment Not Qualifying As Fair Value Hedge Net GainLossFromHedgedFirmCommitmentNotQualifyingAsFairValueHedgeNet	0	USD
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	2360700000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	1199100000	USD
CY2020	us-gaap	Interest And Debt Expense InterestAndDebtExpense	188200000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	2435300000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	-23200000	USD
CY2019	us-gaap	Interest And Debt Expense InterestAndDebtExpense	177400000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	2453700000	USD
CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	-39500000	USD
CY2018	us-gaap	Interest And Debt Expense InterestAndDebtExpense	167300000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	127500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-910600000	USD
CY2018	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	13600000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-924200000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-814200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	865500000	USD
CY2019	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	14000000.0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	851500000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	37300000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	359400000	USD
CY2020	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	22500000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	336900000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	374200000	USD
CY2020	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Changes in the liability for unpaid claims and claim adjustment expenses are as follows: </span></div><div><span><br/></span></div><div style="margin-bottom:6pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:62.668%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.494%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.524%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.494%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.524%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.496%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2019</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2018</span></td></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="15" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(in millions of dollars)</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Balance at January 1</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23,076.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23,149.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23,222.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Less Reinsurance Recoverable</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,246.8 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,227.3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,182.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net Balance at January 1</span></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20,829.9 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20,921.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">21,040.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Incurred Related to</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Current Year</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">6,327.8 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">6,113.2 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">5,832.3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Prior Years</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Interest</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">997.8 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,036.5 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,049.8 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> All Other Incurred</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">878.7 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(274.1)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(106.2)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Foreign Currency</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">65.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">76.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(110.7)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total Incurred</span></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">8,270.2 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">6,951.6 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">6,665.2 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Paid Related to</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Current Year</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(2,727.0)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(2,532.4)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(2,354.7)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Prior Years</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(4,430.3)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(4,511.0)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(4,428.8)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total Paid</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(7,157.3)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(7,043.4)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(6,783.5)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Reserves Ceded Pursuant to Reinsurance Transaction</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(6,141.5)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net Balance at December 31</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">15,801.3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20,829.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20,921.7 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%"> Plus Reinsurance Recoverable</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">8,378.9 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,246.8 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,227.3 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Balance at December 31</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">24,180.2 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23,076.7 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23,149.0 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div>
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23076700000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23149000000.0	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23222000000.0	USD
CY2019Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2246800000	USD
CY2018Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2227300000	USD
CY2017Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2182000000.0	USD
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	20829900000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	20921700000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	21040000000.0	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	6327800000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	6113200000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	5832300000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	2727000000.0	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	2532400000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	2354700000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4430300000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4511000000.0	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4428800000	USD
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	7157300000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	7043400000	USD
CY2018	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	6783500000	USD
CY2020	unm	Reserves Ceded Pursuant To Reinsurance Transaction ReservesCededPursuantToReinsuranceTransaction	-6141500000	USD
CY2019	unm	Reserves Ceded Pursuant To Reinsurance Transaction ReservesCededPursuantToReinsuranceTransaction	0	USD
CY2018	unm	Reserves Ceded Pursuant To Reinsurance Transaction ReservesCededPursuantToReinsuranceTransaction	0	USD
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	15801300000	USD
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	20829900000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	20921700000	USD
CY2020Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	8378900000	USD
CY2019Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2246800000	USD
CY2018Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2227300000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	24180200000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23076700000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23149000000.0	USD
CY2020	unm	Longterm Care Reserve Increase Before Tax LongtermCareReserveIncreaseBeforeTax	151500000	USD
CY2018	unm	Longterm Care Reserve Increase Before Tax LongtermCareReserveIncreaseBeforeTax	750800000	USD
CY2020Q4	unm	Policy And Contract Benefits PolicyAndContractBenefits	1855400000	USD
CY2019Q4	unm	Policy And Contract Benefits PolicyAndContractBenefits	1745500000	USD
CY2018Q4	unm	Policy And Contract Benefits PolicyAndContractBenefits	1695700000	USD
CY2020Q4	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	49653000000.0	USD
CY2019Q4	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	47780100000	USD
CY2018Q4	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	44841900000	USD
CY2020Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	51508400000	USD
CY2019Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	49525600000	USD
CY2018Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	46537600000	USD
CY2020Q4	unm	Life Reserves For Future Policy And Contract Benefits LifeReservesForFuturePolicyAndContractBenefits	8371700000	USD
CY2019Q4	unm	Life Reserves For Future Policy And Contract Benefits LifeReservesForFuturePolicyAndContractBenefits	8435700000	USD
CY2018Q4	unm	Life Reserves For Future Policy And Contract Benefits LifeReservesForFuturePolicyAndContractBenefits	8330900000	USD
CY2020Q4	unm	Accident And Health Active Life Reserves AccidentAndHealthActiveLifeReserves	12730900000	USD
CY2019Q4	unm	Accident And Health Active Life Reserves AccidentAndHealthActiveLifeReserves	12210100000	USD
CY2018Q4	unm	Accident And Health Active Life Reserves AccidentAndHealthActiveLifeReserves	11837400000	USD
CY2020Q4	unm	Unrealized Adjustment To Reserves For Future Policy And Contract Benefits UnrealizedAdjustmentToReservesForFuturePolicyAndContractBenefits	6225600000	USD
CY2019Q4	unm	Unrealized Adjustment To Reserves For Future Policy And Contract Benefits UnrealizedAdjustmentToReservesForFuturePolicyAndContractBenefits	5803100000	USD
CY2018Q4	unm	Unrealized Adjustment To Reserves For Future Policy And Contract Benefits UnrealizedAdjustmentToReservesForFuturePolicyAndContractBenefits	3220300000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	24180200000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23076700000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	23149000000.0	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	171000000.0	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	281800000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	104400000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	250200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	757000000.0	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesTax	-614200000	USD
CY2020	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance Tax Expense ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceTaxExpense	-138200000	USD
CY2019	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance Tax Expense ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceTaxExpense	-511700000	USD
CY2018	unm	Change In Adjustment To Deferred Acquisition Costs And Reserves For Future Policy And Contract Benefits Net Of Reinsurance Tax Expense ChangeInAdjustmentToDeferredAcquisitionCostsAndReservesForFuturePolicyAndContractBenefitsNetOfReinsuranceTaxExpense	371700000	USD
CY2020	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-23800000	USD
CY2019	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-17000000.0	USD
CY2018	unm	Other Comprehensive Income Loss Net Gain On Hedges Adjustment Tax OtherComprehensiveIncomeLossNetGainOnHedgesAdjustmentTax	-8200000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	4300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-200000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	600000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	34800000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	9300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-17000000.0	USD
CY2020	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	220100000	USD
CY2019	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	501000000.0	USD
CY2018	us-gaap	Income Tax Expense Benefit Intraperiod Tax Allocation IncomeTaxExpenseBenefitIntraperiodTaxAllocation	-129900000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	unm	Effective Income Tax Rate Reconciliation Net Operating Loss Carryback Due To Cares Act Percent EffectiveIncomeTaxRateReconciliationNetOperatingLossCarrybackDueToCARESActPercent	0.038
CY2019	unm	Effective Income Tax Rate Reconciliation Net Operating Loss Carryback Due To Cares Act Percent EffectiveIncomeTaxRateReconciliationNetOperatingLossCarrybackDueToCARESActPercent	0
CY2018	unm	Effective Income Tax Rate Reconciliation Net Operating Loss Carryback Due To Cares Act Percent EffectiveIncomeTaxRateReconciliationNetOperatingLossCarrybackDueToCARESActPercent	0
CY2020	unm	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0
CY2019	unm	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0
CY2018	unm	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Act Transition Taxon Accumulated Foreign Earnings Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActTransitionTaxonAccumulatedForeignEarningsPercent	0.018
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.008
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.005
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Exempt Income EffectiveIncomeTaxRateReconciliationTaxExemptIncome	0.013
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.013
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.011
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.024
CY2020	unm	Effective Income Tax Rate Reconciliation Policyholder Reserves Percent EffectiveIncomeTaxRateReconciliationPolicyholderReservesPercent	0.007
CY2019	unm	Effective Income Tax Rate Reconciliation Policyholder Reserves Percent EffectiveIncomeTaxRateReconciliationPolicyholderReservesPercent	0
CY2018	unm	Effective Income Tax Rate Reconciliation Policyholder Reserves Percent EffectiveIncomeTaxRateReconciliationPolicyholderReservesPercent	-0.024
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.019
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.010
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.001
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.177
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.204
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.166
CY2020Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	1279600000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	1154600000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	218700000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	201600000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	52900000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	19400000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1551200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1375600000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	14500000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	28300000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1536700000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1347300000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	185500000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	115600000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	74700000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	58500000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	1443500000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	1213700000	USD
CY2020Q4	unm	Deferred Tax Liabilities Deferred Expense Prepaid Insurance Premium DeferredTaxLiabilitiesDeferredExpensePrepaidInsurancePremium	180400000	USD
CY2019Q4	unm	Deferred Tax Liabilities Deferred Expense Prepaid Insurance Premium DeferredTaxLiabilitiesDeferredExpensePrepaidInsurancePremium	10800000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	68700000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	44100000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1952800000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1442700000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	416100000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	95400000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	924700000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	1289500000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	492600000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	39300000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	92600000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	135200000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	964000000.0	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1382100000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	627800000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-98400000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	273600000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	194600000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1500000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1300000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-600000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	-19700000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	-100000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	33400000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-116600000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	274800000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	227400000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	250500000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-9500000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-114600000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1000000.0	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-100000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-200000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	36100000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	7800000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	16600000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-8200000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	287600000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	7000000.0	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-123000000.0	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	171000000.0	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	281800000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	104400000	USD
CY2019	us-gaap	Tax Cuts And Jobs Act Of2017 Measurement Period Adjustment Income Tax Expense Benefit TaxCutsAndJobsActOf2017MeasurementPeriodAdjustmentIncomeTaxExpenseBenefit	11500000	USD
CY2020	unm	Income Taxes Receivable Net Operating Loss Cares Act IncomeTaxesReceivableNetOperatingLossCARESAct	36500000	USD
CY2020Q4	unm	Tax Cutsand Jobs Actof2017 Complete Accounting Undistributed Accumulated Earningsof Foreign Subsidiaryforwhich Unrecognized Deferred Tax Liabilities Have Not Been Recorded TaxCutsandJobsActof2017CompleteAccountingUndistributedAccumulatedEarningsofForeignSubsidiaryforwhichUnrecognizedDeferredTaxLiabilitiesHaveNotBeenRecorded	700000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	241000000.0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	262200000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1400000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	21000000.0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	21100000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	261500000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	300000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	100000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	700000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	219700000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	241000000.0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	262200000	USD
CY2020Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	105900000	USD
CY2019Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	127100000	USD
CY2018Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	148200000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	113800000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	113900000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	114000000.0	USD
CY2020Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	105900000	USD
CY2019Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	127100000	USD
CY2018Q4	unm	Tax Attributable To Temporary Items Included Above TaxAttributableToTemporaryItemsIncludedAbove	148200000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	12800000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	20600000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	12800000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	14500000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	28300000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-13800000	USD
CY2019	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	9900000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	200000000.0	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	35100000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	139700000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	-6000000.0	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	-8400000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Noncurrent Net DeferredFinanceCostsNoncurrentNet	34800000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Noncurrent Net DeferredFinanceCostsNoncurrentNet	35400000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3345700000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2926900000	USD
CY2020Q4	us-gaap	Debt Current DebtCurrent	0	USD
CY2020Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	0	USD
CY2019Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	300000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	399700000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	3345700000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	3326600000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	2000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	350000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	775000000.0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	2247500000	USD
CY2020Q4	unm	Unum Group Percentage Ownershipof Provident Financing Trust UnumGroupPercentageOwnershipofProvidentFinancingTrust	1	Rate
CY2019	unm	Cost Related To Early Retirement Of Debt CostRelatedToEarlyRetirementOfDebt	27300000	USD
CY2020	us-gaap	Interest Paid InterestPaid	178100000	USD
CY2019	us-gaap	Interest Paid InterestPaid	172900000	USD
CY2018	us-gaap	Interest Paid InterestPaid	167300000	USD
CY2020Q4	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear	0.0650
CY2019Q4	us-gaap	Defined Benefit Plan Health Care Cost Trend Rate Assumed Next Fiscal Year DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear	0.0650
CY2020Q4	us-gaap	Defined Benefit Plan Ultimate Health Care Cost Trend Rate1 DefinedBenefitPlanUltimateHealthCareCostTrendRate1	0.0500
CY2020	us-gaap	Defined Benefit Plan Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate DefinedBenefitPlanYearHealthCareCostTrendRateReachesUltimateTrendRate	2027
CY2020	us-gaap	Net Income Loss NetIncomeLoss	793000000.0	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	1100300000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	523400000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	203642000.0	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	209728900	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	219635600	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	113300	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	125500	shares
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	423000.0	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	203755300	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	209854400	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	220058600	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.89
CY2019	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	12300000	shares
CY2018	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	8700000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.25
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.38
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.89
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.24
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.38
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1600000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1100000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	600000	shares
CY2020	us-gaap	Stock Repurchase Program Expiration Date StockRepurchaseProgramExpirationDate	2020-11-23
CY2020	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2019	unm	Shares Repurchased Cost Commissions SharesRepurchasedCostCommissions	400000	USD
CY2018	unm	Shares Repurchased Cost Commissions SharesRepurchasedCostCommissions	700000	USD
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000.0	shares
CY2020Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	0.10
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	100000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	300000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	700000	USD
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	USD
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	USD
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	30400000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	26600000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	26300000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	327200000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	327600000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	26100000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	22700000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense Net Of Tax AllocatedShareBasedCompensationExpenseNetOfTax	20900000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	4400000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	6100000	USD
CY2018	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	4600000	USD
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9621900000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9576300000	USD
CY2018	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9171100000	USD
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	94100000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	116500000	USD
CY2018	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	142600000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	337900000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	9378100000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	9365600000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	8986100000	USD
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	628800000	USD
CY2019	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	650100000	USD
CY2018	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	667200000	USD
CY2020	unm	Negative Ceding Commission NegativeCedingCommission	438000000	USD
CY2020	unm	Income Taxes Receivable Net Operating Loss Cares Act IncomeTaxesReceivableNetOperatingLossCARESAct	36500000	USD
CY2020Q4	unm	Number Of Companies That Make Up Majority Of Reinsurance Recoverable NumberOfCompaniesThatMakeUpMajorityOfReinsuranceRecoverable	9
CY2020	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	3	Integer
CY2020	us-gaap	Deferred Policy Acquisition Costs Text Block1 DeferredPolicyAcquisitionCostsTextBlock1	<table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:100.000%"><tr><td style="width:1.0%"/><td style="width:46.581%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.218%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.814%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.218%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.814%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.218%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.814%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.223%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Unum</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Colonial</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Unum US</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">International</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Life</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-bottom:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total</span></td></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="21" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(in millions of dollars)</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Deferred Acquisition Costs</span></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Year Ended December 31, 2020</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Beginning of Year</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,223.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">26.4 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,074.6 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,324.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Capitalization</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">291.5 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">12.1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">272.6 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">576.2 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Amortization</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(341.0)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(7.4)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(257.7)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(606.1)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Adjustment Related to Unrealized Investment Gains and Losses</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(4.8)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(17.6)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(22.4)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Foreign Currency</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">0.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">0.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">End of Year</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,168.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">32.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,071.9 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,272.6 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:12pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Year Ended December 31, 2019</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Beginning of Year</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,239.4 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,050.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,309.4 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Capitalization</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">334.5 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">12.8 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">311.3 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">658.6 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Amortization</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(344.0)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(7.1)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(258.8)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(609.9)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Adjustment Related to Unrealized Investment Gains and Losses</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(6.9)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(27.9)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(34.8)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Foreign Currency</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">0.7 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">0.7 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">End of Year</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,223.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">26.4 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,074.6 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,324.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:14pt"><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:3pt double #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:100%">Year Ended December 31, 2018</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Beginning of Year</span></td><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,205.4 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">21.3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">957.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,184.6 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Capitalization</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">344.0 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">8.1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">315.9 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">668.0 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Amortization</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(315.1)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(8.2)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(242.2)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(565.5)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Adjustment Related to Unrealized Investment Gains and Losses</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">5.1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">18.4 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23.5 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Foreign Currency</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(1.2)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(1.2)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">End of Year</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,239.4 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">20.0 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,050.0 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,309.4 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table>
CY2020Q4	us-gaap	Sales Type And Direct Financing Leases Lease Receivable Undiscounted Excess Amount SalesTypeAndDirectFinancingLeasesLeaseReceivableUndiscountedExcessAmount	15700000	USD
CY2020Q4	us-gaap	Assets Assets	70625800000	USD
CY2019Q4	us-gaap	Assets Assets	67013400000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	353000000.0	USD
CY2019Q4	us-gaap	Goodwill Goodwill	351700000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	48600000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	29400000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	1300000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	1900000	USD
CY2020	us-gaap	Lease Cost LeaseCost	47300000	USD
CY2019	us-gaap	Lease Cost LeaseCost	27500000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	30800000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	28900000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0437
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0460
CY2018	us-gaap	Operating Leases Rent Expense Minimum Rentals OperatingLeasesRentExpenseMinimumRentals	29200000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	25400000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	22800000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	16500000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	12700000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	9800000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	34400000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	121600000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	105900000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	82900000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	108600000	USD
CY2020	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	12700000	USD
CY2020Q4	us-gaap	Premiums Earned Net PremiumsEarnedNet	2319900000	USD
CY2020Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	2318100000	USD
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	2368700000	USD
CY2020Q1	us-gaap	Premiums Earned Net PremiumsEarnedNet	2371400000	USD
CY2020Q4	us-gaap	Net Investment Income NetInvestmentIncome	593500000	USD
CY2020Q3	us-gaap	Net Investment Income NetInvestmentIncome	613200000	USD
CY2020Q2	us-gaap	Net Investment Income NetInvestmentIncome	569000000.0	USD
CY2020Q1	us-gaap	Net Investment Income NetInvestmentIncome	585000000.0	USD
CY2020Q4	us-gaap	Gain Loss On Investments GainLossOnInvestments	1304900000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	4400000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	33800000	USD
CY2020Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	-144000000.0	USD
CY2020Q4	us-gaap	Revenues Revenues	4273500000	USD
CY2020Q3	us-gaap	Revenues Revenues	2996300000	USD
CY2020Q2	us-gaap	Revenues Revenues	3021200000	USD
CY2020Q1	us-gaap	Revenues Revenues	2871100000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	124700000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	299600000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	337600000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	202100000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	135400000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	231100000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	265500000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	161000000.0	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.66
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.13
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.30
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.79
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.66
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.13
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.30
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.79
CY2019Q4	us-gaap	Premiums Earned Net PremiumsEarnedNet	2352600000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	2331200000	USD
CY2019Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	2343100000	USD
CY2019Q1	us-gaap	Premiums Earned Net PremiumsEarnedNet	2338700000	USD
CY2019Q4	us-gaap	Net Investment Income NetInvestmentIncome	616300000	USD
CY2019Q3	us-gaap	Net Investment Income NetInvestmentIncome	599400000	USD
CY2019Q2	us-gaap	Net Investment Income NetInvestmentIncome	624900000	USD
CY2019Q1	us-gaap	Net Investment Income NetInvestmentIncome	594700000	USD
CY2019Q4	us-gaap	Gain Loss On Investments GainLossOnInvestments	9200000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-26200000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	-7300000	USD
CY2019Q1	us-gaap	Gain Loss On Investments GainLossOnInvestments	1100000	USD
CY2019Q4	us-gaap	Revenues Revenues	3034600000	USD
CY2019Q3	us-gaap	Revenues Revenues	2960000000.0	USD
CY2019Q2	us-gaap	Revenues Revenues	3016700000	USD
CY2019Q1	us-gaap	Revenues Revenues	2987600000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	377400000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	299400000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	352000000.0	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	353300000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	296200000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	242000000.0	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	281200000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	280900000	USD
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.44
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.16
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.33
CY2019Q4	us-gaap	Supplementary Insurance Information Other Policy Claims And Benefits Payable SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable	1745500000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.31
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.44
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.16
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.33
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.31
CY2020Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	45064300000	USD
CY2020Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Carrying Amount SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCarryingAmount	52683500000	USD
CY2020Q4	us-gaap	Supplementary Insurance Information Deferred Policy Acquisition Costs SupplementaryInsuranceInformationDeferredPolicyAcquisitionCosts	2272600000	USD
CY2020Q4	us-gaap	Supplementary Insurance Information Liability For Future Policy Benefits Losses Claims And Loss Expense Reserves SupplementaryInsuranceInformationLiabilityForFuturePolicyBenefitsLossesClaimsAndLossExpenseReserves	49653000000.0	USD
CY2020Q4	us-gaap	Supplementary Insurance Information Unearned Premiums SupplementaryInsuranceInformationUnearnedPremiums	349300000	USD
CY2020Q4	us-gaap	Supplementary Insurance Information Other Policy Claims And Benefits Payable SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable	1855400000	USD
CY2019Q4	us-gaap	Supplementary Insurance Information Deferred Policy Acquisition Costs SupplementaryInsuranceInformationDeferredPolicyAcquisitionCosts	2324000000.0	USD
CY2019Q4	us-gaap	Supplementary Insurance Information Liability For Future Policy Benefits Losses Claims And Loss Expense Reserves SupplementaryInsuranceInformationLiabilityForFuturePolicyBenefitsLossesClaimsAndLossExpenseReserves	47780100000	USD
CY2019Q4	us-gaap	Supplementary Insurance Information Unearned Premiums SupplementaryInsuranceInformationUnearnedPremiums	363900000	USD
CY2020	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	9378100000	USD
CY2020	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	2360700000	USD
CY2020	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	8972900000	USD
CY2020	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	606100000	USD
CY2020	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	2619100000	USD
CY2019	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	9365600000	USD
CY2019	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	2435300000	USD
CY2019	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	7496200000	USD
CY2019	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	609900000	USD
CY2019	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	2510700000	USD
CY2018	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	8986100000	USD
CY2018	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	2453700000	USD
CY2018	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	8020400000	USD
CY2018	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	565500000	USD
CY2018	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	2384800000	USD
CY2020Q4	srt	Life Insurance In Force Gross LifeInsuranceInForceGross	979755700000	USD
CY2020Q4	srt	Life Insurance In Force Ceded LifeInsuranceInForceCeded	41550900000	USD
CY2020Q4	srt	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	896400000	USD
CY2020Q4	srt	Life Insurance In Force Net LifeInsuranceInForceNet	939101200000	USD
CY2020Q4	srt	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.001
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9621900000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	337900000	USD
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	94100000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	9378100000	USD
CY2020	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.010
CY2019Q4	srt	Life Insurance In Force Gross LifeInsuranceInForceGross	990371000000.0	USD
CY2019Q4	srt	Life Insurance In Force Ceded LifeInsuranceInForceCeded	41669800000	USD
CY2019Q4	srt	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	1018400000	USD
CY2019Q4	srt	Life Insurance In Force Net LifeInsuranceInForceNet	949719600000	USD
CY2019Q4	srt	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.001
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9576300000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	327200000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	116500000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	9365600000	USD
CY2019	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.012
CY2018Q4	srt	Life Insurance In Force Gross LifeInsuranceInForceGross	937300800000	USD
CY2018Q4	srt	Life Insurance In Force Ceded LifeInsuranceInForceCeded	40902800000	USD
CY2018Q4	srt	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	1089300000	USD
CY2018Q4	srt	Life Insurance In Force Net LifeInsuranceInForceNet	897487300000	USD
CY2018Q4	srt	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.001
CY2018	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9171100000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	327600000	USD
CY2018	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	142600000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	8986100000	USD
CY2018	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.016

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$UNM
Unum Group Stock $unm

2020 Q4 Form 10-K Financial Statement

#000000551321000015 Filed on February 17, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$UNM Unum Group Stock $unm

2020 Q4 Form 10-K Financial Statement

#000000551321000015 Filed on February 17, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$UNM
Unum Group Stock $unm