HUM


Line plots across dimensions of each concept
Tables

Table of contents



us-gaap:CommonStockValue

us-gaap:CommonStockParOrStatedValuePerShare
us-gaap:StatementEquityComponents
us-gaap:SharesIssued

us-gaap:CommonStockSharesIssued

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:Revenues
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:PremiumsEarnedNet

us-gaap:SellingGeneralAndAdministrativeExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:InterestExpense
us-gaap:ConsolidationItems

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxExpenseBenefit

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:Assets

us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:AssetsCurrent

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:ReceivablesNetCurrent
us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:OtherAssetsCurrent
us-gaap:ConcentrationRiskByBenchmark

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill
us-gaap:StatementBusinessSegments

us-gaap:IntangibleAssetsNetExcludingGoodwill
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:OtherAssetsNoncurrent
us-gaap:ConcentrationRiskByBenchmark

us-gaap:LiabilitiesCurrent

us-gaap:DebtCurrent
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LongTermDebtCurrent

us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
us-gaap:ConcentrationRiskByBenchmark

us-gaap:LongTermDebtNoncurrent
us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:OtherLiabilitiesNoncurrent
us-gaap:ConcentrationRiskByBenchmark

us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:TreasuryStockValue

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:StatementEquityComponents

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends

us-gaap:PaymentsForRepurchaseOfCommonStock
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentInterestRateStatedPercentage

us-gaap:EffectiveIncomeTaxRateContinuingOperations

us-gaap:ShareBasedCompensation

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

hum:ComprehensiveIncomeLossNetofTaxAttributableToEquityMethodInvestments
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType, us-gaap:VariableRate
hum:DebtInstrumentComponentOfBaseRateBasisSpreadOnVariableRate
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType
hum:DebtInstrumentMinimumDrawOnLoanCommitmentPerAgreement

hum:DepreciationAndAmortizationClassifiedAsBenefitExpense

hum:DepreciationAndAmortizationIncomeStatement
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

hum:GovernmentAndHealthPlanMemberSubsidiesAmount

hum:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingEquityMethodInvestments
us-gaap:StatementEquityComponents

hum:PercentageOfRiskScoreCalculatedFromClaimsSubmittedThroughEDS
us-gaap:MajorCustomers
hum:PercentageOfTotalPremiumAndServicesRevenues

hum:ProceedsFromStockOptionsExercisedAndOther
us-gaap:ConsolidationItems
hum:RevenuesIntersegment
us-gaap:ConsolidationItems, us-gaap:ProductOrService
us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

hum:RevenuesPremiumsAndServiceExternal
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

hum:ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares

hum:ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
us-gaap:StatementEquityComponents

us-gaap:AmortizationOfIntangibleAssets

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount

us-gaap:BenefitsLossesAndExpenses
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CommonStockDividendsPerShareCashPaid
us-gaap:SubsequentEventType
us-gaap:SubsequentEventType
us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:ComprehensiveIncomeNetOfTax
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType, us-gaap:VariableRate
us-gaap:DebtInstrumentBasisSpreadOnVariableRate1

us-gaap:DebtSecuritiesAvailableForSaleRealizedGain

us-gaap:DebtSecuritiesAvailableForSaleRealizedGainLoss

us-gaap:DebtSecuritiesAvailableForSaleRealizedLoss

us-gaap:Depreciation

us-gaap:Dividends
us-gaap:SubsequentEventType

us-gaap:DividendsCommonStockCash
us-gaap:StatementEquityComponents

us-gaap:GoodwillAcquiredDuringPeriod
us-gaap:BusinessAcquisition
us-gaap:StatementBusinessSegments

us-gaap:IncomeLossFromEquityMethodInvestments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncreaseDecreaseInBookOverdrafts

us-gaap:IncreaseDecreaseInContractWithCustomerLiability

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes

us-gaap:IncreaseDecreaseInHealthCareInsuranceLiabilities

us-gaap:IncreaseDecreaseInOtherDeposits

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInReceivables
us-gaap:AwardType
us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestPaidNet

us-gaap:InvestmentIncomeInterestAndDividend
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1
us-gaap:StatementBusinessSegments

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1
us-gaap:StatementBusinessSegments

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1
us-gaap:StatementBusinessSegments
us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:LineOfCreditFacilityCommitmentFeePercentage
us-gaap:Range, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:OperatingIncomeLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax

us-gaap:OtherNonoperatingIncomeExpense
us-gaap:ConsolidationItems

us-gaap:OtherOperatingActivitiesCashFlowStatement

us-gaap:PaymentsForLossesAndLossAdjustmentExpense
us-gaap:StatementBusinessSegments

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt
us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType
us-gaap:PaymentsToAcquireBusinessesGross

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired

us-gaap:PolicyholderBenefitsAndClaimsIncurredHealthCare
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:ProceedsFromIncomeTaxRefunds

us-gaap:ProceedsFromIssuanceOfCommercialPaper

us-gaap:ProceedsFromIssuanceOfSeniorLongTermDebt

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

us-gaap:ProceedsFromNotesPayable
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax
us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:MajorCustomers
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesRestrictedStockAwardGross
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised

us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross
us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised
us-gaap:StatementEquityComponents

us-gaap:SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense
us-gaap:StatementBusinessSegments

us-gaap:SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense
us-gaap:StatementBusinessSegments

us-gaap:TreasuryStockValueAcquiredCostMethod
us-gaap:StatementEquityComponents

hum:BookOverdraftLiability
us-gaap:BalanceSheetLocation, us-gaap:OptionIndexedToIssuersEquityEquity
hum:FinancialAssetsFairValueDisclosure
us-gaap:ConcentrationRiskByBenchmark
hum:NetAssetLiability
us-gaap:ConcentrationRiskByBenchmark
hum:NetCurrentLiabilityAsset
us-gaap:ConcentrationRiskByBenchmark
hum:NetNoncurrentAssetLiability

us-gaap:AdditionalPaidInCapitalCommonStock

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:AssetsFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtSecurities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument
us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent

us-gaap:AvailableForSaleSecuritiesDebtSecuritiesNoncurrent
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByMeasurementFrequency

us-gaap:ContractWithCustomerLiabilityCurrent

us-gaap:CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption
us-gaap:StatementEquityComponents
us-gaap:DebtInstrument, us-gaap:LongtermDebtType
us-gaap:DebtInstrumentFaceAmount
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType
us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType
us-gaap:FairValueByMeasurementBasis
us-gaap:DebtInstrumentFairValue

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
us-gaap:FinancialInstrument
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument, us-gaap:MeasurementInputType
us-gaap:DerivativeAssetLiabilityNetMeasurementInput

us-gaap:EquityMethodInvestments
us-gaap:BalanceSheetLocation, us-gaap:OptionIndexedToIssuersEquityEquity
us-gaap:FinancialLiabilitiesFairValueDisclosure

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FiniteLivedIntangibleAssetsGross
us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:LiabilityForClaimsAndClaimsAdjustmentExpense
us-gaap:StatementBusinessSegments

us-gaap:LiabilityForFuturePolicyBenefits
us-gaap:StatementBusinessSegments
us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount

us-gaap:ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementBusinessSegments
us-gaap:ShortTermDebtType
us-gaap:ShortTermBorrowings

us-gaap:ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:TreasuryStockShares

Tables

  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:CommonStockValue ██████████████████████████▄▄▄▄▄▄▄▄▄▄▁▁3333333333333333333333333333333333333333333333333333323232323232323232323131NANANA31NANANA
us-gaap:CommonStockParOrStatedValuePerShare ▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁██████0.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.170.170.170.170.170.17NANANA0.17NANANA
 us-gaap:SharesIssued us-gaap:StatementEquityComponents us-gaap:CommonStock▄▄▄▄▄▄▄▄▄▄▄▄198198198198198198198198198198198198NA198NANANA198NANANA197NANANA196NANANA194NANANA193NANANA190NANANA189NANANA
us-gaap:CommonStockSharesIssued █████████████████████▇▇▇▇▆▆▅▅▄▄▄▄▄▃▃▂▁198198198198198198198198198198198198198198198198198198198198198197197197197196196195195194194194194193192192191190NANANA189NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding 132NA134135135NA138138138NA145145148NA150150150NA150151152NA156157156NA158159160NA162164166NA166169169NA169170170NANANANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic 132NA133135135NA137137137NA144144147NA149149149NA148149150NA154155155NA157157158NA160162163NA164167167NA167168168NANANANA
us-gaap:EarningsPerShareBasic ▅▅▆█▆▅▆▄▅▄▅▆█▁▅▄▄▃▄▅▅▃▄▄▄▃▄▅▅▄▅▄▄▄▅▅▄▃▄▄▄▄▄▄▄3.583.875.166.964.182.64.681.43.561.33.464.497.54-2.683.012.081.570.682.112.882.860.961.872.222.37-0.192.342.662.971.212.652.191.511.222.712.761.880.642.352.021.541.491.81.681.23
us-gaap:EarningsPerShareDiluted ▅▅▆█▆▅▆▄▅▄▅▆█▁▅▄▄▃▄▅▅▃▄▄▄▃▄▅▅▄▅▄▄▄▅▅▄▃▄▄▄▄▄▄▄3.563.845.146.944.162.584.651.393.531.293.444.467.49-2.682.982.061.560.672.092.852.820.941.852.192.35-0.192.312.632.951.192.622.161.491.22.672.711.860.632.322.01.521.481.781.671.22
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:Revenues █▆▆▆▆▅▅▅▅▄▄▅▅▄▅▅▅▅▅▅▅▄▄▄▄▃▃▃▃▂▂▂▃▂▂▂▂▁▁▂▁▁▁▁▁189351629516241162451610714168142061425914279131891328213534137621287813694140071380013361133631373213833123281223812222117121018710319103211048695579651969910219905693009284919083508424865284407633771678987711
 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:HealthcareServices█▇▇▇▆▆▆▆▅▆▆▆▆▇▇▆▆▆▆▆▆▅▅▄▄▃▂▂▂▁▁7085669666026387609861915966599156636018600059825958633163616244618657785973597658785290514749674611435839933911377034263179NANANANANANANANANANANANANANA
 us-gaap:Revenues us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,us-gaap:Retail█▅▅▅▅▂▂▂▂▁▁▁167621420714088141581401312036120731203912107109481104611299NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:PremiumsEarnedNet █▆▆▆▆▅▅▅▅▄▄▄▄▄▄▄▄▄▄▄▄▃▃▃▃▁▂▂▂▁▁▁▂1836215809157121577615651137051371213713138111282412955132031339812560133711365013440129621298713212132481168511607115841108395629698970198688980908891669775NA885288498766NA813483768161NANANANA
us-gaap:SellingGeneralAndAdministrativeExpense ██▆▄▄█▆▅▄▆▄▂▃▇▅▄▅▆▄▅▆█▆▅▅▆▂▂▂▄▁▁▁211721291889170316602115190017611749187316881453155320241759172617681868168818171945212118981835178519081540146114461655140813841383NA136111921255NA100210931060NANANANA
 us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:GroupAndSpecialty▅▄▄▃▄▇▆▇█▃▁▂▂▇▄▄429419413406413455445447463412385394399449421423NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:HealthcareServices█▇▇▇▆▇▆▆▅▆▆▆▆▇▇▆▆▆▆▆▆▅▅▄▄▃▂▂▂▂▁6800648163486135588859955720574954415765572656775680603260405941591355035659571356065097490847264390418338003751361633343013NANANANANANANANANANANANANANA
 us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,us-gaap:Retail▇█▅▄▃▇▅▄▄▄▂▁15321642131012061148154313521210122212941081963NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:InterestExpense ▅▅▅▅▅▅▄▄▄▇▅▅▄▄▄▄▄▃▄▄▃█▂▂▂▂▂▂▂▁▁▁▁605862606259535353765958494847474746474746843835353535353527262626NA272727NA262626NANANANA
 us-gaap:InterestExpense us-gaap:ConsolidationItems hum:CorporateAndEliminations▄▄▅▄▅▄▃▃▃█▄▄▂▁▁▁▁▁▁▁6058626062595353537659584948474747464747NANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments ▅▄▅▇▅▄▅▃▅▄▅▆█▁▅▅▄▃▅▅▅▃▄▅▅▂▄▅▅▃▅▄▄▄▅▅▄▃▅▄▄▄▄▄▄71759388812297464369011970749079910421689-486902636500246648793744287551646686-49586654730282675564390313698726496174622535416398469439293
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:GroupAndSpecialty▆▁▄▄▇▄▅▅█▅▆▆▇▄▅▆105-14645165-11818021147931011711137124NANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:HealthcareServices▇▅▆▆▄▄▅▅▄▆▆▇▇▇█▇▇▇█▆▆▄▅▅▅▃▄▃▃▁▃24218021121217215820620617321324027024426728827124124428422323014620220618513715612411866144NANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,us-gaap:Retail▆▁▅█▃▂▅▄▁▂▅▅685275639856465339634493267391610607NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest ▅▄▆█▅▃▆▁▅▄▅725591889124174943891019707490799NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:GroupAndSpecialty▆▁▄▄▇▄▅▅█▅▆105-14645165-1181802114793NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,hum:HealthcareServices█▂▅▆▂▁▅▅▂▅▇250178212224175160215206173213240NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,us-gaap:Retail▆▁▅█▃▂▅▄▁▂▅685275639856465339634493267391610NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IncomeTaxExpenseBenefit ▅▃▄▅▄▃▅▁▅▅▅▆█▂▇▆▅▄▆▆▆▄▅▅▆▂▅▅▅▃▅▅▄2527920030118383266-174216306300392574-85452325266145334362314142261302318-1921823425790249208142NA253266181NA229195158NANANANA
us-gaap:NetIncomeLoss ▅▅▆▇▅▄▆▄▅▄▅▆█▁▅▄▄▃▄▅▅▄▄▄▅▃▅▅▅▄▅▄▄▄▅▅▄▃▅▄▄▄▄▄▄4735126899405663556441934911844996501115-401450311234101314431430145290344368-30368420473192426356248199444460315107393340258250301281205
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▄▄▆█▅▃▅▁▄▁▄473512689940566355644193491184499NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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us-gaap:Liabilities ▇▅▅▅▅▄▅██▅▇▇▇▄▅▄▄▃▃▄▄▃▃▃▃▂▂▂▂▂▁▃▃▁▂▁▁▁2227817037175791704117508152521689724059233721733621745213002147814711181811636216409143591394315301155801382014206131211284111419112971151311810111321010612400124669645120411000899339179NANANA8377NANANA
us-gaap:LiabilitiesAndStockholdersEquity █▆▆▆▆▅▅██▅▇▇▇▅▆▅▅▄▄▅▅▄▄▄▃▃▃▃▃▂▂▃▃▂▂▂▁▁3463329074291802891328349254132749034270334532717832956322533171225396294662723626934247052429625384256242346624331231212256620735209032084820974199791879720855207001770819899175941716016103NANANA14153NANANA
us-gaap:StockholdersEquity ██▇▇▆▅▆▅▅▅▇▆▅▆▇▆▆▅▅▅▅▅▅▅▅▄▄▄▄▃▃▃▃▂▂▂▁▁123551203711601118721084110161105931021110081984211211109531023410685112851087410525103461035310083100449646101251000097259316960693359164884786918455823480637857758672266924NANANA5776NANANA
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 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:RetainedEarnings█▇▇▆▅▄▃▃▂▂▂▁178711748317045164291556315072147861421114086136701354213101NA11454NANANA11017NANANA9916NANANA8942NANANA7881NANANA6825NANANA5529NANANA4429NANANA
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us-gaap:AssetsCurrent ▇▅▅▅▅▄▅█▇▄▆▆▆▄▅▄▄▃▃▄▄▃▃▃▃▂▂▂▂▂▂▃▃▁▂▂▁▁2455119888203242016019673169481907726864239321740223185225682231716190196541773617844157111577316975174021471215636140861397512300125731262812678117101167814071140561118113632114751109610137NANANA9252NANANA
us-gaap:CashAndCashEquivalentsAtCarryingValue ▅▃▅▄▃▂▃▇▇▃█▇▇▃▆▂▂▂▁▂▂▂▂▁▁▁▁▁▁▁▁▃▃▁▃▁▁▁▂▂▂▁605440545527477838772343414280528855404298658139842538776769242928012571159722501946193527051593166211381255151913981306136338693656137740191567175616732922199818131613NANANA
us-gaap:ReceivablesNetCurrent ▆▃▂▂▆▂▃▄▃▂▂█▅▃▁█▅▃▂▆▅▃▂▆▄▂▂▄▃▁▁▂▄▂▂▄▃▂20091056848904195510151062147112768549222430183812807652553173711619862129169011681004207414609508241593132173364289813301034103615461219959NANANA823NANANA
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us-gaap:PropertyPlantAndEquipmentNet ██▇▇▆▆▆▆▆▅▅▅▅▅▅▅▅▄▄▄▄▄▄▄▃▃▃▃▃▃▂▂▂▂▁▁▁▁2023195518641796175417351685162615951584156015431525150514781452142013841343129912581419134912891244121811801133111910981034976939912850822819815NANANA679NANANA
us-gaap:Goodwill █▆▆▆▆▆▆▆▅▄▄▄▄▄▄▄▄▄▄▄▃▅▅▅▅▅▅▅▅▅▂▂▂▂▁▁▁▁44433928392239223897389738953895376032813281328032793272327232663265326532663266323137113695369636993733371636383641364029622792278527402579257725762567NANANA1992NANANA
 us-gaap:Goodwill us-gaap:StatementBusinessSegments hum:HealthcareServices█▄▄▄▄▄▄▄▃▂▂▂▂▂▁▁▁▁▁▁▁▁▅▅264721322126212621012101209920992080196119611960195919521818181218111811181218121777177722332234NA22712413248424872486NANANANANANANANANANANANANANANA
 us-gaap:Goodwill us-gaap:StatementBusinessSegments us-gaap:Retail▄▄▄▄▄▄▄▄15351535153515351535153515351535NA1059NANANA1059NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill ▄▁▁▁▂▂▂▂▂▂▂▂▂▂▃▃▃▃▄▄▄▆▆▇▇██▇██▅▄▅▄▄▄▄▄396177194211228245263284276226227245262280298316336357379401419572607629657693724675703731465440456435380394390399NANANANANANANA
 us-gaap:IntangibleAssetsNetExcludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass us-gaap:CustomerContracts▅▁▁▂▂▂▃▃▃▁▂▂▂▂▃▃▃▃▄▄▄▆▆▇▇██▇▇█▃335150166182196212227242232165178192206219233246259274289304317396415434454482505458476496269NANA247NANANANANANANANANANANA
us-gaap:OtherAssetsNoncurrent ▅▄▃▃▃▂▂▃▄▅▆▆▅▆██▇▇▅▅▄▃▄▅▄▄▄▃▄▃▂▂▂▁▁▁▁▁21301834160515681555137513801506180521662214219221672226278927312465250220352005176116751704215518481774169716791712168512861233121611651140112610991082NANANA921NANANA
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us-gaap:LiabilitiesCurrent ▆▄▄▄▄▃▄█▆▃▆▅▅▂▄▃▃▂▂▃▃▂▂▂▂▁▁▂▂▁▁▃▃▁▂▁▁▁1483010929111061153911927100771132418768154559406144181370513504782211816993410105815277428973917773557769788077146323655167706944637563698676882360568516635563645744NANANA5259NANANA
us-gaap:DebtCurrent █▁▁▅▇▇1898699699134917181694NANANANANANANANANANANANANANANANA512NANA0NANANANANANANANANANANANANANANANANANANA
 us-gaap:LongTermDebtCurrent us-gaap:DebtInstrument,us-gaap:LongtermDebtType hum:A2.50PercentSeniorNotesDueDecember2020,us-gaap:SeniorNotes▁█398399NANANA0NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent ▆▄▄▄▄▃▆█▇▄▅▅▅▂▃▄▄▂▂▃▄▂▂▂▂▁▂▂▂▂▁▂▂▁▂▁▁▁53993754364038323719306754136952626640694888469346752467293338734074221222163292355421852068255927521821201021742321204219622081212317832332194419161624NANANA1307NANANA
 us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent us-gaap:ConcentrationRiskByBenchmark hum:CmsSubsidiesOrDiscounts▄▁▂▄▄▁▅█12413567811259128550316882588NA1085NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
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 us-gaap:OtherLiabilitiesNoncurrent us-gaap:ConcentrationRiskByBenchmark hum:RiskCorridorSettlementsMedicarePartD▇▁██▇▃▆▃130611421371348912287NA28NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
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us-gaap:StockholdersEquity ██▇▇▆▅▆▅▅▅▇▆▅▆▇▆▆▅▅▅▅▅▅▅▅▄▄▄▄▃▃▃▃▂▂▂▁▁123551203711601118721084110161105931021110081984211211109531023410685112851087410525103461035310083100449646101251000097259316960693359164884786918455823480637857758672266924NANANA5776NANANA
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 us-gaap:StockholdersEquity us-gaap:StatementEquityComponents us-gaap:RetainedEarnings█▇▇▆▅▄▃▃▂▂▂▁178711748317045164291556315072147861421114086136701354213101NA11454NANANA11017NANANA9916NANANA8942NANANA7881NANANA6825NANANA5529NANANA4429NANANA
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us-gaap:NetCashProvidedByUsedInOperatingActivities ▄▄▆▅▅▃▃▄▇▁▆▄█▁█▃▄▄▅▃▄▄▅▄▄▄▅▄▄▄▂47451224421434896-333-1055-1253686-29112863-1064205-27734503-2764823371032-608107193954-200671-161147173412205-1334NA2346NANANA795NANANA754NANANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▃▄▄▅▆▅▁▆▅▃▄▅▄▄▅▆▅▅▄█▅▆▄▇▅▅▄▆▅▃▅-1210-801-566-56145-447-2353118-405-1165-698-152-926-828-237131-428-297-6051316-94305-772575-171-39-995244-392-1212-414NA-190NANANA-690NANANA-527NANANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities █▂▂▃▄▂▂▄▆▁▃▄▆▅▄▃▄▅▂▃▄▂▅▃▄▄▃▃▄▅▃2736-1184-1127-477493-1019-1281-171532-1747-439-28126970974-227176934-1080-404-2-1268930-44424-62-416-29672950-758NA123NANANA-21NANANA-27NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▄▄▆▅▅▃▃▄▇▁▆▄█▁█▃▄▄▅▃▄▄▅▄▄▄▅▄▄▄▂47451224421434896-333-1055-1253686-29112863-1064205-27734503-2764823371032-608107193954-200671-161147173412205-1334NA2346NANANA795NANANA754NANANANA
us-gaap:NetIncomeLoss ▅▅▆▇▅▄▆▄▅▄▅▆█▁▅▄▄▃▄▅▅▄▄▄▅▃▅▅▅▄▅▄▄▄▅▅▄▃▅▄▄▄▄▄▄4735126899405663556441934911844996501115-401450311234101314431430145290344368-30368420473192426356248199444460315107393340258250301281205
 us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents us-gaap:RetainedEarnings▄▄▆█▅▃▅▁▄▁▄473512689940566355644193491184499NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▃▄▄▅▆▅▁▆▅▃▄▅▄▄▅▆▅▅▄█▅▆▄▇▅▅▄▆▅▃▅-1210-801-566-56145-447-2353118-405-1165-698-152-926-828-237131-428-297-6051316-94305-772575-171-39-995244-392-1212-414NA-190NANANA-690NANANA-527NANANANA
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▆█▇▄▃▅▅▃▃▄▄▂▃▃▃▃▃▃▃▃▃▅▄▂▂▃▃▁▁▂▂1922302101571391761641381341501431111221321391311251391251361231671451101061311239790106119NA86NANANA70NANANA39NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities █▂▂▃▄▂▂▄▆▁▃▄▆▅▄▃▄▅▂▃▄▂▅▃▄▄▃▃▄▅▃2736-1184-1127-477493-1019-1281-171532-1747-439-28126970974-227176934-1080-404-2-1268930-44424-62-416-29672950-758NA123NANANA-21NANANA-27NANANANA
us-gaap:PaymentsOfDividends ████▇▇▇▇▄▄▄▄▂▂▁▁▂▁▁▁▂▁▁▁▂▁▁▁▁▁▁73757474687069695758585747444343474343424443434244434241424142NA41NANANA0NANANANANANANANA
us-gaap:PaymentsOfDividends ████▇▇▇▇▄▄▄▄▂▂▁▁▂▁▁▁▂▁▁▁▂▁▁▁▁▁▁73757474687069695758585747444343474343424443434244434241424142NA41NANANA0NANANANANANANANA
us-gaap:PaymentsForRepurchaseOfCommonStock ▁▁▅▁▁▅▂▁▁█▂▁█▁▁▁▁▁▁▂▁▄▂▁▁▂▁▂▁▁▂17601000010796201425115462414157429227159305666021181034920694137945235NA151NANANA88NANANA7NANANANA
  2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType hum:A3.85PercentSeniorNotesDueOctober2024,us-gaap:SeniorNotes▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄0.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.0385NANA0.0NANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType hum:A4.500PercentSeniorNotesDueApril2025,us-gaap:SeniorNotes0.045NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType hum:A4.875PercentSeniorNotesDueApril2030,us-gaap:SeniorNotes0.04875NANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANANA
 us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument,us-gaap:LongtermDebtType hum:A4.95PercentSeniorNotesDueOctober2044,us-gaap:SeniorNotes▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄0.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.0495NANA0.0NANANANANANANANANANANANANANANANANANANA

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value333333333333333333333333333333333333333333333333333332323232323232323232313131
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.20.20.20.20.20.20.20.20.20.20.20.2

Common Stock Par Or Stated Value Per Share

us-gaap:CommonStockParOrStatedValuePerShare



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value0.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.16670.170.170.170.170.170.170.17
Percentage of CommonStockParOrStatedValuePerShare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Shares Issued

us-gaap:StatementEquityComponents

us-gaap:SharesIssued

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-31
Value198198198198198198198198198198198198198198197196194193190189
Percentage of SharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Issued

us-gaap:CommonStockSharesIssued



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value198198198198198198198198198198198198198198198198198198198198198197197197197196196195195194194194194193192192191190189
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Common Stock Shares Authorized

Weighted Average Number Of Diluted Shares Outstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value132134135135138138138145145148150150150150151152156157156158159160162164166166169169169170170
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Weighted Average Number Of Shares Outstanding Basic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value132133135135137137137144144147149149149148149150154155155157157158160162163164167167167168168
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Basic

us-gaap:EarningsPerShareBasic



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value3.583.875.166.964.182.64.681.43.561.33.464.497.54-2.683.012.081.570.682.112.882.860.961.872.222.37-0.192.342.662.971.212.652.191.511.222.712.761.880.642.352.021.541.491.81.681.23
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Earnings Per Share Diluted

us-gaap:EarningsPerShareDiluted



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value3.563.845.146.944.162.584.651.393.531.293.444.467.49-2.682.982.061.560.672.092.852.820.941.852.192.35-0.192.312.632.951.192.622.161.491.22.672.711.860.632.322.01.521.481.781.671.22
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Revenues

us-gaap:Revenues



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value189351629516241162451610714168142061425914279131891328213534137621287813694140071380013361133631373213833123281223812222117121018710319103211048695579651969910219905693009284919083508424865284407633771678987711
Percentage of Revenues100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax4465.8100.04132.64576.14537.2100.03728.63732.74366.7100.05956.15884.3100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-6777-6483-6338-6174-5891-5970-5742-5763-5502-5895-5874-5856-5822-6314-6269-6149-6104-5924-5784-5633
Percentage of Revenues-35.8-39.8-39.0-38.0-36.6-42.1-40.4-40.4-38.5-44.7-44.2-43.3-42.3-49.0-45.8-43.9-44.2-44.3-43.3-41.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-1598.3-39.8-1612.7-1739.2-1659.4-42.1-1507.1-1508.6-1682.6-44.7-2634.1-2546.1-42.3-49.0-45.8-43.9-44.2-44.3-43.3-41.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax hum:CorporateAndEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value1865187518891874188719091894190619701891185318281877183718291871
Percentage of Revenues9.811.511.611.511.713.513.313.413.814.314.013.513.614.313.413.4
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax439.911.5480.7527.9531.513.5497.1499.0602.414.3830.9794.813.614.313.413.4
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:GroupAndSpecialty956.40.0944.5971.0972.70.0880.9916.30.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value7085669666026387609861915966599156636018600059825958633163616244618657785973597658785290514749674611435839933911377034263179
Percentage of Revenues37.441.140.739.337.943.742.042.039.745.645.244.243.349.246.544.644.843.244.743.542.542.942.140.639.442.838.737.936.035.832.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1671.041.11679.91799.21717.743.71565.91568.31731.845.62690.62600.943.349.246.544.644.843.244.743.542.542.942.140.639.442.838.737.936.035.832.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:HealthcareServices3148.90.03493.14068.23909.00.03615.83545.05445.20.07500.07207.26770.50.09786.29182.49516.90.08656.52621.11866.00.01569.21496.11482.60.01217.41203.41196.80.01173.1

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value167621420714088141581401312036120731203912107109481104611299
Percentage of Revenues88.587.286.787.287.085.085.084.484.883.083.283.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax3953.387.23584.73988.23947.385.03168.83151.63702.483.04953.44912.6
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments us-gaap:Retail419050.00.0352200.0283160.0280260.00.01207300.0401300.00.00.00.00.0

Premiums Earned Net

us-gaap:PremiumsEarnedNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value1836215809157121577615651137051371213713138111282412955132031339812560133711365013440129621298713212132481168511607115841108395629698970198688980908891669775885288498766813483768161
Percentage of PremiumsEarnedNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax4330.797.03998.04443.94408.796.73599.03589.84223.597.25809.45740.497.497.597.697.597.497.097.296.295.894.894.894.894.693.994.094.094.194.094.294.595.795.295.395.496.696.896.7

Other Income

Deferred Policy Acquisition Cost Amortization Expense

Selling General And Administrative Expense

us-gaap:SellingGeneralAndAdministrativeExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value211721291889170316602115190017611749187316881453155320241759172617681868168818171945212118981835178519081540146114461655140813841383136111921255100210931060
Percentage of SellingGeneralAndAdministrativeExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax499.313.1480.7479.7467.614.9498.7461.0534.914.2757.0631.711.315.712.812.312.814.012.613.214.117.215.515.015.218.714.914.213.817.314.614.313.514.612.813.711.912.612.6

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-6644-6413-6182-6044-5789-5879-5619-5648-5381-5651-5556-5623-5546-6116-6023-5894-5897-5730-5566-5474
Percentage of SellingGeneralAndAdministrativeExpense-313.8-301.2-327.3-354.9-348.7-278.0-295.7-320.7-307.7-301.7-329.1-387.0-357.1-302.2-342.4-341.5-333.5-306.7-329.7-301.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-1567.0-39.4-1573.0-1702.5-1630.7-41.5-1474.8-1478.5-1645.6-42.8-2491.5-2444.8-40.3-47.5-44.0-42.1-42.7-42.9-41.7-39.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax hum:CorporateAndEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value429419413406413455445447463412385394399449421423
Percentage of SellingGeneralAndAdministrativeExpense20.319.721.923.824.921.523.425.426.522.022.827.125.722.223.924.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax101.22.6105.1114.4116.33.2116.8117.0141.63.1172.6171.32.93.53.13.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:GroupAndSpecialty220.00.0206.5210.4212.90.0207.0214.90.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value6800648163486135588859955720574954415765572656775680603260405941591355035659571356065097490847264390418338003751361633343013
Percentage of SellingGeneralAndAdministrativeExpense321.2304.4336.1360.2354.7283.5301.1326.5311.1307.8339.2390.7365.7298.0343.4344.2334.4294.6335.2314.4288.2240.3258.6257.5245.9219.2246.8256.7250.1201.5214.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax1603.839.81615.31728.21658.642.31501.31505.01663.943.72567.72468.341.346.844.142.442.841.242.341.640.541.340.138.737.541.136.836.334.534.931.2
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:HealthcareServices3022.20.03358.73907.63774.40.03466.73401.85231.70.07157.56839.86454.50.09292.38736.89096.90.08201.42505.71779.70.01496.31423.51411.60.01158.51154.21147.90.01111.8

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value15321642131012061148154313521210122212941081963
Percentage of SellingGeneralAndAdministrativeExpense72.477.169.370.869.273.071.268.769.969.164.066.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax361.310.1333.3339.7323.410.9354.9316.8373.79.8484.8418.7
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments us-gaap:Retail38300.00.032750.024120.022960.00.0135200.040333.30.00.00.00.0

Interest Expense

us-gaap:InterestExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value605862606259535353765958494847474746474746843835353535353527262626272727262626
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax14.20.415.816.917.50.413.913.916.20.626.525.20.40.40.30.30.30.30.40.30.30.70.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.3

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value6058626062595353537659584948474747464747
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax14.20.415.816.917.50.413.913.916.20.626.525.20.40.40.30.30.30.30.40.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax hum:CorporateAndEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value71759388812297464369011970749079910421689-486902636500246648793744287551646686-49586654730282675564390313698726496174622535416398469439293
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax169.13.6226.0346.2210.13.1236.55.0216.23.7358.3453.012.3-3.86.64.53.61.84.85.85.42.34.55.35.9-0.55.76.37.03.07.05.83.83.57.57.85.42.17.46.24.95.26.15.63.8

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-31528434156-56-48-25-813-15-141-165-53842-48-40-49-52-2-2258
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments-43.947.93.812.7-7.5-11.0-2.8-4278.9-2.1-28.8-20.7-5.149.99.9-4.4-7.7-10.4-0.8-0.332.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-74.31.78.743.9-15.8-0.3-6.6-212.8-4.6-1.1-74.0-23.06.1-0.4-0.3-0.3-0.4-0.0-0.01.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax hum:CorporateAndEliminations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value105-14645165-11818021147931011711137124
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments14.6-24.60.50.422.1-2.59.0421.129.89.611.69.710.1-2.34.119.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax24.8-0.91.01.446.5-0.121.320.964.50.441.743.91.20.10.30.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:GroupAndSpecialty53.80.02.02.685.10.037.738.50.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value24218021121217215820620617321324027024426728827124124428422323014620220618513715612411866144
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments33.830.423.817.223.136.222.91084.224.543.530.025.914.4-54.931.942.648.299.243.828.130.950.936.731.927.0-279.626.619.016.223.421.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax57.11.153.759.748.51.154.153.952.91.6107.6117.41.82.12.11.91.71.82.11.61.71.21.71.71.61.31.51.21.10.71.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:HealthcareServices107.60.0111.6135.0110.30.0124.8121.9166.30.0300.0325.3277.30.0443.1398.5370.80.0411.697.873.00.061.662.059.50.047.638.237.50.053.1

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value685275639856465339634493267391610607
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments95.546.472.069.762.377.870.42594.737.879.876.358.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax161.61.7162.6241.1131.02.4166.4129.181.73.0273.5263.9
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments us-gaap:Retail17125.00.015975.017120.09300.00.063400.016433.30.00.00.00.0

Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value725591889124174943891019707490799
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax171.03.6226.2349.6211.03.1238.85.0216.23.7358.3

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-31528434156-56-48-25-813-15-141-165
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest-43.448.13.812.6-7.5-11.0-2.7-4278.9-2.1-28.8-20.7
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-74.31.78.743.9-15.8-0.3-6.6-212.8-4.6-1.1-74.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax hum:CorporateAndEliminations0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value105-14645165-1181802114793
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest14.5-24.70.40.422.0-2.58.9421.129.89.611.6
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax24.8-0.91.01.446.5-0.121.320.964.50.441.7
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:GroupAndSpecialty53.80.02.02.685.10.037.738.50.00.00.0

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value250178212224175160215206173213240
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest34.530.123.818.023.436.523.61084.224.543.530.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax59.01.153.963.149.31.156.453.952.91.6107.6
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments hum:HealthcareServices111.10.0112.2142.7112.20.0130.3121.9166.30.0300.0

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value685275639856465339634493267391610
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest94.546.571.969.062.177.469.72594.737.879.876.3
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax161.61.7162.6241.1131.02.4166.4129.181.73.0273.5
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:OperatingSegments us-gaap:Retail17125.00.015975.017120.09300.00.063400.016433.30.00.00.0

Income Tax Expense Benefit

us-gaap:IncomeTaxExpenseBenefit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value2527920030118383266-174216306300392574-85452325266145334362314142261302318-1921823425790249208142253266181229195158
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax59.40.550.984.851.50.669.8-45.566.12.3134.5170.44.2-0.73.32.31.91.12.52.62.31.22.12.52.7-0.22.12.32.50.92.62.11.42.72.92.02.72.31.9

Net Income Loss

us-gaap:NetIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value4735126899405663556441934911844996501115-401450311234101314431430145290344368-30368420473192426356248199444460315107393340258250301281205
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.63.1175.3264.8159.42.5169.050.5150.21.4223.8282.68.1-3.13.32.21.70.82.33.13.11.22.42.83.1-0.33.64.14.52.04.43.72.42.24.85.03.41.34.73.93.13.33.93.62.7

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value473512689940566355644193491184499
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.63.1175.3264.8159.42.5169.050.5150.21.4223.8
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.0

Assets

us-gaap:Assets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value346332907429180289132834925413274903427033453271783295632253317122539629466272362693424705242962538425624234662433123121225662073520903208482097419979187972085520700177081989917594171601610314153
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Liabilities

us-gaap:Liabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value22278170371757917041175081525216897240592337217336217452130021478147111818116362164091435913943153011558013820142061312112841114191129711513118101113210106124001246696451204110008993391798377
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets64.358.660.258.961.860.061.570.269.963.866.066.067.757.961.760.160.958.157.460.360.858.958.456.756.955.154.055.256.355.753.859.560.254.560.556.957.957.059.2

Liabilities And Stockholders Equity

us-gaap:LiabilitiesAndStockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value346332907429180289132834925413274903427033453271783295632253317122539629466272362693424705242962538425624234662433123121225662073520903208482097419979187972085520700177081989917594171601610314153
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value123551203711601118721084110161105931021110081984211211109531023410685112851087410525103461035310083100449646101251000097259316960693359164884786918455823480637857758672266924577644574028
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets35.741.439.841.138.240.038.529.830.136.234.034.032.342.138.339.939.141.942.639.739.241.141.643.343.144.946.044.843.744.346.240.539.845.539.543.142.143.040.80.00.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value48156177112-10-159-206-176-1541912-5-665822315838630312042-17514
Percentage of StockholdersEquity0.41.31.50.9-0.1-1.6-1.9-1.7-1.50.20.1-0.0-0.60.62.31.74.43.81.70.7-3.90.3
Percentage of Assets0.10.50.60.4-0.0-0.6-0.7-0.5-0.50.10.0-0.0-0.30.21.00.81.91.70.70.30.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value2857282026082763272225352707267226262445264123062562253023302267210119381737165815741497
Percentage of StockholdersEquity23.123.422.523.325.124.925.626.226.024.823.621.124.024.524.224.323.724.025.128.735.337.2
Percentage of Assets8.29.78.99.69.610.09.87.87.89.08.07.110.110.29.910.910.510.910.811.70.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value33333333333333333333333333333333323231313131
Percentage of StockholdersEquity0.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.40.40.40.50.50.70.8
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.20.20.20.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value178711748317045164291556315072147861421114086136701354213101114541101799168942788168255529442933892742
Percentage of StockholdersEquity144.6145.2146.9138.4143.6148.3139.6139.2139.7138.9120.8119.6107.2106.5102.896.089.184.679.976.776.168.1
Percentage of Assets51.660.158.456.854.959.353.841.542.150.341.140.645.144.642.343.139.438.534.331.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-8454-8455-8262-7465-7467-7320-6727-6529-6510-6325-5017-4482-3298-3292-2856-2084-1553-1035-494-385-363-256
Percentage of StockholdersEquity-68.4-70.2-71.2-62.9-68.9-72.0-63.5-63.9-64.6-64.3-44.8-40.9-30.9-31.8-29.6-22.4-17.6-12.8-7.1-6.7-8.1-6.4
Percentage of Assets-24.4-29.1-28.3-25.8-26.3-28.8-24.5-19.1-19.5-23.3-15.2-13.9-13.0-13.3-12.2-10.1-7.8-5.8-3.1-2.70.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Assets Current

us-gaap:AssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value24551198882032420160196731694819077268642393217402231852256822317161901965417736178441571115773169751740214712156361408613975123001257312628126781171011678140711405611181136321147511096101379252
Percentage of AssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets70.968.469.769.769.466.769.478.471.564.070.470.070.463.866.765.166.363.664.966.967.962.764.360.961.959.360.160.660.458.662.167.567.963.168.565.264.763.065.4

Cash And Cash Equivalents At Carrying Value

us-gaap:CashAndCashEquivalentsAtCarryingValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312008-12-312007-12-31
Value60544054552747783877234341428052885540429865813984253877676924292801257115972250194619352705159316621138125515191398130613633869365613774019156717561673292219981813161319702040
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets17.513.918.916.513.79.215.123.526.514.929.925.226.615.323.08.910.410.46.68.97.68.211.16.97.45.56.07.36.76.57.318.617.77.820.28.910.210.40.00.00.011.40.00.0

Accounts Receivable Net Current

Receivables Net Current

us-gaap:ReceivablesNetCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value20091056848904195510151062147112768549222430183812807652553173711619862129169011681004207414609508241593132173364289813301034103615461219959823
Percentage of ReceivablesNetCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.83.62.93.16.94.03.94.33.83.12.87.55.85.02.69.46.44.74.18.46.65.04.19.06.54.63.97.66.33.73.44.36.45.85.28.87.16.05.8

us-gaap:AccountsNotesLoansAndFinancingReceivableByReceivableType

us-gaap:TradeAccountsReceivable



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value141141135136148152162
Percentage of ReceivablesNetCurrent7.016.614.97.013.910.312.7
Percentage of Assets0.40.50.50.50.50.40.5
Percentage of Assets us-gaap:TradeAccountsReceivable0.00.00.00.00.00.00.0

Other Assets Current

us-gaap:OtherAssetsCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value5384380635194487396535644178441040592949377638843849343847915337556847125767555552144011383928542605212222321960181816701615142211811027706721669583505
Percentage of OtherAssetsCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.513.112.115.514.014.015.212.912.110.911.512.012.113.516.319.620.719.123.721.920.317.115.812.311.510.210.79.48.78.48.66.85.75.83.64.13.93.63.6

us-gaap:ConcentrationRiskByBenchmark

hum:CmsSubsidiesOrDiscounts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value89458533738833317226842101
Percentage of OtherAssetsCurrent16.615.49.68.68.44.86.41.03.4
Percentage of Assets2.62.01.21.31.20.71.00.10.4
Percentage of Assets hum:CmsSubsidiesOrDiscounts0.00.00.00.00.00.00.00.00.0

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value59511111015664
Percentage of OtherAssetsCurrent1.10.10.30.20.30.40.10.10.1
Percentage of Assets0.20.00.00.00.00.10.00.00.0
Percentage of Assets hum:RiskCorridorSettlementsMedicarePartD0.00.00.00.00.00.00.00.00.0

Land

Machinery And Equipment Gross

Property Plant And Equipment Gross

Accumulated Depreciation Depletion And Amortization Property Plant And Equipment

Property Plant And Equipment Net

us-gaap:PropertyPlantAndEquipmentNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2023195518641796175417351685162615951584156015431525150514781452142013841343129912581419134912891244121811801133111910981034976939912850822819815679
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets5.86.76.46.26.26.86.14.74.85.84.74.84.85.95.05.35.35.65.55.14.96.05.55.65.55.95.65.45.35.55.54.74.55.24.34.74.85.14.8

Goodwill

us-gaap:Goodwill



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-31
Value4443392839223922389738973895389537603281328132803279327232723266326532653266326632313711369536963699373337163638364136402962279227852740257925772576256719921963
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets12.813.513.413.613.715.314.211.411.212.110.010.210.312.911.112.012.113.213.412.912.615.815.216.016.418.017.817.517.418.215.813.413.515.513.014.615.015.914.10.0

us-gaap:StatementBusinessSegments

hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302013-12-312013-09-302013-06-302013-03-312012-12-31
Value26472132212621262101210120992099208019611961196019591952181818121811181118121812177717772233223422712413248424872486
Percentage of Goodwill59.654.354.254.253.953.953.953.955.359.859.859.859.759.755.655.555.555.555.555.555.047.960.460.460.864.968.368.368.3
Percentage of Assets7.67.37.37.47.48.37.66.16.27.26.06.16.27.76.26.76.77.37.57.16.97.69.29.711.011.511.911.912.4
Percentage of Assets hum:HealthcareServices0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312016-12-31
Value1535153515351535153515351535153510591059
Percentage of Goodwill34.539.139.139.139.439.439.439.432.332.4
Percentage of Assets4.45.35.35.35.46.05.64.53.94.2
Percentage of Assets us-gaap:Retail0.00.00.00.00.00.00.00.00.00.0

Intangible Assets Net Excluding Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value396177194211228245263284276226227245262280298316336357379401419572607629657693724675703731465440456435380394390399
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.10.60.70.70.81.01.00.80.80.80.70.80.81.11.01.21.21.41.61.61.62.42.52.72.93.33.53.23.43.72.52.12.22.51.92.22.32.5

us-gaap:FiniteLivedIntangibleAssetsByMajorClass

hum:NoncompetesAndOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value111111243344344456710121416192123262831343230
Percentage of IntangibleAssetsNetExcludingGoodwill0.30.60.50.50.40.40.81.41.11.31.81.61.11.41.31.31.51.71.82.52.92.42.63.03.23.33.64.14.44.76.96.9
Percentage of Assets0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.10.10.10.10.10.10.10.10.20.20.2
Percentage of Assets hum:NoncompetesAndOther0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ContractualRights



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value2426272831313234363818202122232426272829293032272728293031323329
Percentage of IntangibleAssetsNetExcludingGoodwill6.114.713.913.313.612.712.212.013.016.87.98.28.07.97.77.67.77.67.47.26.95.25.34.34.14.04.04.44.44.47.16.7
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.2
Percentage of Assets us-gaap:ContractualRights0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CustomerContracts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value335150166182196212227242232165178192206219233246259274289304317396415434454482505458476496269247
Percentage of IntangibleAssetsNetExcludingGoodwill84.684.785.686.386.086.586.385.284.173.078.478.478.678.278.277.877.176.876.375.875.769.268.469.069.169.669.867.967.767.957.856.8
Percentage of Assets1.00.50.60.60.70.80.80.70.70.60.50.60.60.90.80.91.01.11.21.21.21.71.71.92.02.32.42.22.32.51.41.4
Percentage of Assets us-gaap:CustomerContracts0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TradeNames



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value3600001245202729323538424650555861132144149155160164159165169131129
Percentage of IntangibleAssetsNetExcludingGoodwill9.10.00.00.00.00.40.81.41.88.811.911.812.212.512.813.313.714.014.514.514.623.123.723.723.623.122.723.623.523.128.229.7
Percentage of Assets0.10.00.00.00.00.00.00.00.00.10.10.10.10.10.10.20.20.20.20.20.20.60.60.60.70.80.80.80.80.80.70.7
Percentage of Assets us-gaap:TradeNames0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Finite Lived Intangible Assets Net

Deferred Tax Assets Liabilities Net

Other Assets Noncurrent

us-gaap:OtherAssetsNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value21301834160515681555137513801506180521662214219221672226278927312465250220352005176116751704215518481774169716791712168512861233121611651140112610991082921
Percentage of OtherAssetsNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets6.26.35.55.45.55.45.04.45.48.06.76.86.88.89.510.09.210.18.47.96.97.17.09.38.28.68.18.18.28.46.85.95.96.65.76.46.46.76.5

us-gaap:ConcentrationRiskByBenchmark

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1836252626727640
Percentage of OtherAssetsNoncurrent8.60.31.61.71.70.52.04.20.0
Percentage of Assets0.50.00.10.10.10.00.10.20.0
Percentage of Assets hum:RiskCorridorSettlementsMedicarePartD0.00.00.00.00.00.00.00.00.0

Liabilities Current

us-gaap:LiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value14830109291110611539119271007711324187681545594061441813705135047822118169934101058152774289739177735577697880771463236551677069446375636986768823605685166355636457445259
Percentage of LiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets42.837.638.139.942.139.741.254.846.234.643.742.542.630.840.136.537.533.031.935.335.831.331.934.134.230.531.332.533.131.933.941.642.634.242.836.137.135.737.2

Debt Current

us-gaap:DebtCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312014-09-302013-12-31
Value18986996991349171816945120
Percentage of DebtCurrent100.0100.0100.0100.0100.0100.0100.00.0
Percentage of Assets5.52.42.44.76.16.72.10.0

Long Term Debt Current

us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LongTermDebtCurrent

hum:A2.50PercentSeniorNotesDueDecember2020, us-gaap:SeniorNotes



Period End2020-03-312019-12-312018-12-31
Value3983990
Percentage of LongTermDebtCurrent100.0100.00.0
Percentage of Assets1.11.40.0
Percentage of Assets hum:A2.50PercentSeniorNotesDueDecember2020 us-gaap:SeniorNotes0.00.00.0

Accounts Payable And Accrued Liabilities Current

us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value539937543640383237193067541369526266406948884693467524672933387340742212221632923554218520682559275218212010217423212042196220812123178323321944191616241307
Percentage of AccountsPayableAndAccruedLiabilitiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets15.612.912.513.313.112.119.720.318.715.014.814.614.79.710.014.215.19.09.113.013.99.38.511.112.28.89.610.411.110.210.410.010.310.111.711.111.210.19.2

us-gaap:ConcentrationRiskByBenchmark

hum:CmsSubsidiesOrDiscounts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value124135678112591285503168825881085
Percentage of AccountsPayableAndAccruedLiabilitiesCurrent23.09.521.532.934.616.431.237.226.7
Percentage of Assets3.61.22.74.44.52.06.17.64.0
Percentage of Assets hum:CmsSubsidiesOrDiscounts0.00.00.00.00.00.00.00.00.0

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value148120494863103214232255
Percentage of AccountsPayableAndAccruedLiabilitiesCurrent2.73.21.31.31.73.44.03.36.3
Percentage of Assets0.40.40.20.20.20.40.80.70.9
Percentage of Assets hum:RiskCorridorSettlementsMedicarePartD0.00.00.00.00.00.00.00.00.0

Other Liabilities Current

Long Term Debt

Long Term Debt Noncurrent

us-gaap:LongTermDebtNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value605749675365437743764375477447734772477039774279478037923792379337933821382238233824382538262595259826002603260626082611161616181621165916611664166616681678
Percentage of LongTermDebtNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets17.517.118.415.115.417.217.413.914.317.612.113.315.114.912.913.914.115.515.715.114.916.315.711.211.512.512.512.512.413.18.67.87.89.48.39.59.710.411.9

us-gaap:DebtInstrument, us-gaap:LongtermDebtType

hum:A2.90PercentSeniorNotesDueDecember2022, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value398397397397397396
Percentage of LongTermDebtNoncurrent6.68.07.49.19.19.1
Percentage of Assets1.11.41.41.41.41.6
Percentage of Assets hum:A2.90PercentSeniorNotesDueDecember2022 us-gaap:SeniorNotes0.00.00.00.00.00.0

hum:A3.125PercentSeniorNotesDueAugust2029, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302018-12-31
Value4954954950
Percentage of LongTermDebtNoncurrent8.210.09.20.0
Percentage of Assets1.41.71.70.0
Percentage of Assets hum:A3.125PercentSeniorNotesDueAugust2029 us-gaap:SeniorNotes0.00.00.00.0

hum:A3.15PercentSeniorNotesDueDecember2022, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value598598597597597596
Percentage of LongTermDebtNoncurrent9.912.011.113.613.613.6
Percentage of Assets1.72.12.02.12.12.3
Percentage of Assets hum:A3.15PercentSeniorNotesDueDecember2022 us-gaap:SeniorNotes0.00.00.00.00.00.0

hum:A3.85PercentSeniorNotesDueOctober2024, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value597597597597596597
Percentage of LongTermDebtNoncurrent9.912.011.113.613.613.6
Percentage of Assets1.72.12.02.12.12.3
Percentage of Assets hum:A3.85PercentSeniorNotesDueOctober2024 us-gaap:SeniorNotes0.00.00.00.00.00.0

hum:A3.95PercentSeniorNotesDueAugust2049, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302018-12-31
Value4924924920
Percentage of LongTermDebtNoncurrent8.19.99.20.0
Percentage of Assets1.41.71.70.0
Percentage of Assets hum:A3.95PercentSeniorNotesDueAugust2049 us-gaap:SeniorNotes0.00.00.00.0

hum:A3.95PercentSeniorNotesDueMarch2027, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value596595595595595594
Percentage of LongTermDebtNoncurrent9.812.011.113.613.613.6
Percentage of Assets1.72.02.02.12.12.3
Percentage of Assets hum:A3.95PercentSeniorNotesDueMarch2027 us-gaap:SeniorNotes0.00.00.00.00.00.0

hum:A4.500PercentSeniorNotesDueApril2025, us-gaap:SeniorNotes



Period End2020-03-312019-12-31
Value5940
Percentage of LongTermDebtNoncurrent9.80.0
Percentage of Assets1.70.0
Percentage of Assets hum:A4.500PercentSeniorNotesDueApril2025 us-gaap:SeniorNotes0.00.0

hum:A4.80PercentSeniorNotesDueMarch2047, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value396396396395395396
Percentage of LongTermDebtNoncurrent6.58.07.49.09.09.1
Percentage of Assets1.11.41.41.41.41.6
Percentage of Assets hum:A4.80PercentSeniorNotesDueMarch2047 us-gaap:SeniorNotes0.00.00.00.00.00.0

hum:A4.875PercentSeniorNotesDueApril2030, us-gaap:SeniorNotes



Period End2020-03-312019-12-31
Value4940
Percentage of LongTermDebtNoncurrent8.20.0
Percentage of Assets1.40.0
Percentage of Assets hum:A4.875PercentSeniorNotesDueApril2030 us-gaap:SeniorNotes0.00.0

hum:A8.15PercentSeniorNotesDueJune2038, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value262262262262263263
Percentage of LongTermDebtNoncurrent4.35.34.96.06.06.0
Percentage of Assets0.80.90.90.90.91.0
Percentage of Assets hum:A8.15PercentSeniorNotesDueJune2038 us-gaap:SeniorNotes0.00.00.00.00.00.0

Other Liabilities Noncurrent

us-gaap:OtherLiabilitiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1186935897911992581603321303237457417367263279347278235225357281291312360330289316327334288270321332267283427371272246
Percentage of OtherLiabilitiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.43.23.13.23.52.32.20.90.90.91.41.31.21.00.91.31.01.00.91.41.11.21.31.61.51.41.51.61.61.41.41.51.61.51.42.42.21.71.7

us-gaap:ConcentrationRiskByBenchmark

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value13061142137134891228728
Percentage of OtherLiabilitiesNoncurrent11.06.515.815.013.515.320.227.111.8
Percentage of Assets0.40.20.50.50.50.40.40.30.1
Percentage of Assets hum:RiskCorridorSettlementsMedicarePartD0.00.00.00.00.00.00.00.00.0

Stockholders Equity

us-gaap:StockholdersEquity



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-312008-12-312007-12-31
Value123551203711601118721084110161105931021110081984211211109531023410685112851087410525103461035310083100449646101251000097259316960693359164884786918455823480637857758672266924577644574028
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets35.741.439.841.138.240.038.529.830.136.234.034.032.342.138.339.939.141.942.639.739.241.141.643.343.144.946.044.843.744.346.240.539.845.539.543.142.143.040.80.00.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value48156177112-10-159-206-176-1541912-5-665822315838630312042-17514
Percentage of StockholdersEquity0.41.31.50.9-0.1-1.6-1.9-1.7-1.50.20.1-0.0-0.60.62.31.74.43.81.70.7-3.90.3
Percentage of Assets0.10.50.60.4-0.0-0.6-0.7-0.5-0.50.10.0-0.0-0.30.21.00.81.91.70.70.30.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value2857282026082763272225352707267226262445264123062562253023302267210119381737165815741497
Percentage of StockholdersEquity23.123.422.523.325.124.925.626.226.024.823.621.124.024.524.224.323.724.025.128.735.337.2
Percentage of Assets8.29.78.99.69.610.09.87.87.89.08.07.110.110.29.910.910.510.910.811.70.00.0
Percentage of Assets us-gaap:AdditionalPaidInCapital0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value33333333333333333333333333333333323231313131
Percentage of StockholdersEquity0.30.30.30.30.30.30.30.30.30.30.30.30.30.30.30.40.40.40.50.50.70.8
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.20.20.20.00.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value178711748317045164291556315072147861421114086136701354213101114541101799168942788168255529442933892742
Percentage of StockholdersEquity144.6145.2146.9138.4143.6148.3139.6139.2139.7138.9120.8119.6107.2106.5102.896.089.184.679.976.776.168.1
Percentage of Assets51.660.158.456.854.959.353.841.542.150.341.140.645.144.642.343.139.438.534.331.30.00.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:TreasuryStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-312014-12-312013-12-312012-12-312011-12-312010-12-312009-12-312008-12-312007-12-31
Value-8454-8455-8262-7465-7467-7320-6727-6529-6510-6325-5017-4482-3298-3292-2856-2084-1553-1035-494-385-363-256
Percentage of StockholdersEquity-68.4-70.2-71.2-62.9-68.9-72.0-63.5-63.9-64.6-64.3-44.8-40.9-30.9-31.8-29.6-22.4-17.6-12.8-7.1-6.7-8.1-6.4
Percentage of Assets-24.4-29.1-28.3-25.8-26.3-28.8-24.5-19.1-19.5-23.3-15.2-13.9-13.0-13.3-12.2-10.1-7.8-5.8-3.1-2.70.00.0
Percentage of Assets us-gaap:TreasuryStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Common Stock Value

us-gaap:CommonStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value333333333333333333333333333333333333333333333333333332323232323232323232313131
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.10.20.20.20.20.20.20.20.20.20.20.20.20.20.2

Retained Earnings Accumulated Deficit

us-gaap:RetainedEarningsAccumulatedDeficit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value178711748317045164291556315072147861421114086136701354213101125091145411899114921120511017109601068910302991698139567926689429014868883117881773173467032682566676262584455294429
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets51.660.158.456.854.959.353.841.542.150.341.140.639.445.140.442.241.644.645.142.140.242.340.341.441.143.143.141.739.639.441.135.234.038.533.535.634.134.331.3

Treasury Stock Value

us-gaap:TreasuryStockValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value84548455826274657467732067276529651063255017448244963298328632873287329232923287298328562354223621332084187817841647155315481313118610351034795583494385
Percentage of TreasuryStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets24.429.128.325.826.328.824.519.119.523.315.213.914.213.011.212.112.213.313.512.911.612.29.79.79.510.19.08.67.97.88.26.35.75.85.24.53.43.12.7

Accumulated Other Comprehensive Income Loss Net Of Tax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value48156177112-10-159-206-176-1541912-5-58-66112134765813715322722323326022615819620932838639732731330327918910812042
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.10.50.60.4-0.0-0.6-0.7-0.5-0.50.10.0-0.0-0.2-0.30.40.50.30.20.60.60.91.01.01.11.00.80.91.01.61.92.11.61.51.71.41.10.60.70.3

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value47451224421434896-333-1055-1253686-29112863-1064205-27734503-2764823371032-608107193954-200671-161147173412205-13342346795754
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.83.1621.4403.9252.4-2.4-276.9-32.71127.2-22.11283.9-46.130.6-21.532.9-2.03.52.57.7-4.40.81.67.8-1.65.7-0.211.11.73.92.1-13.823.08.78.9

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value-1210-801-566-56145-447-2353118-405-1165-698-152-926-828-237131-428-297-6051316-94305-772575-171-39-995244-392-1212-414-190-690-527
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-285.4-4.9-144.0-15.840.8-3.2-617.630.9-123.9-8.8-313.0-66.1-6.7-6.4-1.70.9-3.1-2.2-4.59.6-0.72.5-6.34.7-1.5-0.4-9.62.4-3.7-12.7-4.3-1.9-7.5-6.2

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value2736-1184-1127-477493-1019-1281-171532-1747-439-28126970974-227176934-1080-404-2-1268930-44424-62-416-29672950-758123-21-27
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax645.3-7.3-286.8-134.4138.9-7.2-336.2-4.5468.5-13.2-196.9-12.29.25.50.5-1.61.37.0-8.1-2.9-0.0-10.37.6-3.60.2-0.6-4.0-2.90.79.9-7.91.2-0.2-0.3

Net Cash Provided By Used In Operating Activities

us-gaap:NetCashProvidedByUsedInOperatingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value47451224421434896-333-1055-1253686-29112863-1064205-27734503-2764823371032-608107193954-200671-161147173412205-13342346795754
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.83.1621.4403.9252.4-2.4-276.9-32.71127.2-22.11283.9-46.130.6-21.532.9-2.03.52.57.7-4.40.81.67.8-1.65.7-0.211.11.73.92.1-13.823.08.78.9

Net Income Loss

us-gaap:NetIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value4735126899405663556441934911844996501115-401450311234101314431430145290344368-30368420473192426356248199444460315107393340258250301281205
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.63.1175.3264.8159.42.5169.050.5150.21.4223.8282.68.1-3.13.32.21.70.82.33.13.11.22.42.83.1-0.33.64.14.52.04.43.72.42.24.85.03.41.34.73.93.13.33.93.62.7

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value473512689940566355644193491184499
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax111.63.1175.3264.8159.42.5169.050.5150.21.4223.8
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.0

Increase Decrease In Other Operating Capital Net

Net Cash Provided By Used In Investing Activities

us-gaap:NetCashProvidedByUsedInInvestingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value-1210-801-566-56145-447-2353118-405-1165-698-152-926-828-237131-428-297-6051316-94305-772575-171-39-995244-392-1212-414-190-690-527
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax-285.4-4.9-144.0-15.840.8-3.2-617.630.9-123.9-8.8-313.0-66.1-6.7-6.4-1.70.9-3.1-2.2-4.59.6-0.72.5-6.34.7-1.5-0.4-9.62.4-3.7-12.7-4.3-1.9-7.5-6.2

Payments To Acquire Property Plant And Equipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1922302101571391761641381341501431111221321391311251391251361231671451101061311239790106119867039
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Net Cash Provided By Used In Financing Activities

us-gaap:NetCashProvidedByUsedInFinancingActivities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value2736-1184-1127-477493-1019-1281-171532-1747-439-28126970974-227176934-1080-404-2-1268930-44424-62-416-29672950-758123-21-27
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax645.3-7.3-286.8-134.4138.9-7.2-336.2-4.5468.5-13.2-196.9-12.29.25.50.5-1.61.37.0-8.1-2.9-0.0-10.37.6-3.60.2-0.6-4.0-2.90.79.9-7.91.2-0.2-0.3

Repayments Of Long Term Debt

Payments Of Dividends

us-gaap:PaymentsOfDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-31
Value73757474687069695758585747444343474343424443434244434241424142410
Percentage of PaymentsOfDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

Payments Of Dividends

us-gaap:PaymentsOfDividends



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-31
Value73757474687069695758585747444343474343424443434244434241424142410
Percentage of PaymentsOfDividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

Payments For Repurchase Of Common Stock

us-gaap:PaymentsForRepurchaseOfCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value17601000010796201425115462414157429227159305666021181034920694137945235151887
Percentage of PaymentsForRepurchaseOfCommonStock100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Repayments Of Long Term Debt

Debt Instrument Interest Rate Stated Percentage

us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentInterestRateStatedPercentage

hum:A3.85PercentSeniorNotesDueOctober2024, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value0.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.03850.0
Percentage of DebtInstrumentInterestRateStatedPercentage100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations hum:A3.85PercentSeniorNotesDueOctober2024 us-gaap:SeniorNotes0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

hum:A4.500PercentSeniorNotesDueApril2025, us-gaap:SeniorNotes



Period End2020-03-31
Value0.045
Percentage of DebtInstrumentInterestRateStatedPercentage116.9
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations hum:A4.500PercentSeniorNotesDueApril2025 us-gaap:SeniorNotes0.0

hum:A4.875PercentSeniorNotesDueApril2030, us-gaap:SeniorNotes



Period End2020-03-31
Value0.04875
Percentage of DebtInstrumentInterestRateStatedPercentage126.6
Percentage of LongTermDebtAndCapitalLeaseObligations0.0
Percentage of LongTermDebtAndCapitalLeaseObligations hum:A4.875PercentSeniorNotesDueApril2030 us-gaap:SeniorNotes0.0

hum:A4.95PercentSeniorNotesDueOctober2044, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value0.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.04950.0
Percentage of DebtInstrumentInterestRateStatedPercentage128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.6128.60.0
Percentage of LongTermDebtAndCapitalLeaseObligations0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0
Percentage of LongTermDebtAndCapitalLeaseObligations hum:A4.95PercentSeniorNotesDueOctober2044 us-gaap:SeniorNotes0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

Effective Income Tax Rate Continuing Operations

us-gaap:EffectiveIncomeTaxRateContinuingOperations



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value0.3480.2250.2420.2440.291-0.2490.3070.3750.3760.340.5010.5110.5320.5150.4560.4220.4750.4670.4640.3720.3570.3520.3690.3680.3650.3630.3660.3660.3680.3650.379
Percentage of EffectiveIncomeTaxRateContinuingOperations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

Share Based Compensation

us-gaap:ShareBasedCompensation



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value36444343333236343541335726392825231723254422212233192219321414402927
Percentage of ShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Deferred Tax Liabilities

Deferred Tax Assets Net

Unrecognized Tax Benefits

Deferred Tax Assets Valuation Allowance

Operating Lease Right Of Use Asset

Cash And Cash Equivalents Period Increase Decrease

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value60544054552747783877234341428831885540423877
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

hum:ComprehensiveIncomeLossNetofTaxAttributableToEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-32-1-3-2-4000
Percentage of ComprehensiveIncomeLossNetofTaxAttributableToEquityMethodInvestments100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType, us-gaap:VariableRate

hum:DebtInstrumentComponentOfBaseRateBasisSpreadOnVariableRate

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks, us-gaap:SubsequentEvent, us-gaap:FederalFundsEffectiveSwapRate



Period End2020-02-20
Value0.005
Percentage of DebtInstrumentComponentOfBaseRateBasisSpreadOnVariableRate100.0

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks, us-gaap:SubsequentEvent, us-gaap:LondonInterbankOfferedRateLIBOR



Period End2020-02-20
Value0.01
Percentage of DebtInstrumentComponentOfBaseRateBasisSpreadOnVariableRate200.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType

hum:DebtInstrumentMinimumDrawOnLoanCommitmentPerAgreement

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks, us-gaap:SubsequentEvent



Period End2020-02-20
Value300
Percentage of DebtInstrumentMinimumDrawOnLoanCommitmentPerAgreement100.0

hum:DepreciationAndAmortizationClassifiedAsBenefitExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value3025323129312930392826272626312727242324213727272524232422233987710
Percentage of DepreciationAndAmortizationClassifiedAsBenefitExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

hum:DepreciationAndAmortizationIncomeStatement



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value1151151271091071031021001001009492929186898888849093878579829083808077757370666766586458
Percentage of DepreciationAndAmortizationIncomeStatement100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-29-25-29-29-26-28-26-24-38-26-25-25-24-26-29-25-24-19-19-19
Percentage of DepreciationAndAmortizationIncomeStatement-25.2-21.7-22.8-26.6-24.3-27.2-25.5-24.0-38.0-26.0-26.6-27.2-26.1-28.6-33.7-28.1-27.3-21.6-22.6-21.1

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value20212421222221222321212121201922
Percentage of DepreciationAndAmortizationIncomeStatement17.418.318.919.320.621.420.622.023.021.022.322.822.822.022.124.7

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value43354340383840364940343534323332323130404247373536383736362622
Percentage of DepreciationAndAmortizationIncomeStatement37.430.433.936.735.536.939.236.049.040.036.238.037.035.238.436.036.435.235.744.445.254.043.544.343.942.244.645.045.033.829.3

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value818489777371676666626157
Percentage of DepreciationAndAmortizationIncomeStatement70.473.070.170.668.268.965.766.066.062.064.962.0

hum:GovernmentAndHealthPlanMemberSubsidiesAmount



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value350042004000360031003700350033002900370036003200300037003600320029003500330030002500290026002300190034001300120013001200120012001200110010001000900900800
Percentage of GovernmentAndHealthPlanMemberSubsidiesAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

hum:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-108-216512214947-30-22
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-108-216512214947-30-22
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentIncludingEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.0100.0

hum:PercentageOfRiskScoreCalculatedFromClaimsSubmittedThroughEDS



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.50.00.00.00.25
Percentage of PercentageOfRiskScoreCalculatedFromClaimsSubmittedThroughEDS100.00.00.00.0100.0

us-gaap:MajorCustomers

hum:PercentageOfTotalPremiumAndServicesRevenues

hum:Medicaid



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value0.050.00.00.00.040.0
Percentage of PercentageOfTotalPremiumAndServicesRevenues100.00.00.00.0100.00.0

hum:Medicare



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value0.830.019999999999999907-0.0199999999999999070.00.820.0
Percentage of PercentageOfTotalPremiumAndServicesRevenues1660.00.00.00.02050.00.0

hum:MilitaryService



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value0.010.00.00.00.010.0
Percentage of PercentageOfTotalPremiumAndServicesRevenues20.00.00.00.025.00.0

hum:ProceedsFromStockOptionsExercisedAndOther



Period End2020-03-312019-03-31
Value1917
Percentage of ProceedsFromStockOptionsExercisedAndOther100.0100.0

us-gaap:ConsolidationItems

hum:RevenuesIntersegment

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-6867-6570-6417-6234-5946-6027-5794-5809
Percentage of RevenuesIntersegment100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:ProductOrService

hum:CorporateAndEliminations, us-gaap:Product



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-1910-1766-1759-1733-1636-1608-1576-1611
Percentage of RevenuesIntersegment27.826.927.427.827.526.727.227.7

hum:CorporateAndEliminations, us-gaap:Service



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value-4957-4804-4658-4501-4310-4419-4218-4198
Percentage of RevenuesIntersegment72.273.172.672.272.573.372.872.3

us-gaap:ConsolidationItems, us-gaap:ProductOrService, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, us-gaap:Product, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value19101766175917331636160815761611
Percentage of RevenuesIntersegment-27.8-26.9-27.4-27.8-27.5-26.7-27.2-27.7

us-gaap:OperatingSegments, us-gaap:Service, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value75454544
Percentage of RevenuesIntersegment-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1

us-gaap:OperatingSegments, us-gaap:Service, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value49504799465444964306441442144194
Percentage of RevenuesIntersegment-72.1-73.0-72.5-72.1-72.4-73.2-72.7-72.2

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value75454544
Percentage of RevenuesIntersegment-0.1-0.1-0.1-0.1-0.1-0.1-0.1-0.1

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value68606565641362295942602257905805
Percentage of RevenuesIntersegment-99.9-99.9-99.9-99.9-99.9-99.9-99.9-99.9

hum:RevenuesPremiumsAndServiceExternal



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1878616145161051613116006140721409314095
Percentage of RevenuesPremiumsAndServiceExternal100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value18531864187818641878189918851896
Percentage of RevenuesPremiumsAndServiceExternal9.911.511.711.611.713.513.413.5

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value225130189157156169165169
Percentage of RevenuesPremiumsAndServiceExternal1.20.81.21.01.01.21.21.2

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value1670814151140381411013972120021203812009
Percentage of RevenuesPremiumsAndServiceExternal88.987.687.287.587.385.385.485.2

hum:ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value40000.0165000.01000.04000.030000.0140000.010000.060000.0190000.0130000.00.020000.0350000.0150000.010000.010000.0430000.00.00.0100000.0200000.00.00.00.0400000.00.0100000.00.0200000.0100000.00.0600000.0600000.0200000.0
Percentage of ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.00.00.0100.0100.00.00.00.0100.00.0100.00.0100.0100.00.0100.0100.0100.0

hum:ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1760001046118513614742922715924020238547135151367
Percentage of ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3644434333323534354133
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3644434333323534354133
Percentage of AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AmortizationOfIntangibleAssets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-03-312010-03-31
Value211717181820192130211818181818202121222426362828283328282822191717129
Percentage of AmortizationOfIntangibleAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-302016-06-302016-03-312015-09-302015-06-302015-03-312014-09-302014-06-302014-03-312013-09-302013-06-302013-03-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value0000000000001000000001001002345
Percentage of AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BenefitsLossesAndExpenses



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value17861159331537315130152601365113245133971351912623124241243412024133161274513324132531307212668131591304311957116491154110991102019698963297219248895091099803857485298666770280277937
Percentage of BenefitsLossesAndExpenses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-6819-6536-6352-6216-5936-6003-5777-5793-5540-5830-5768-5861-6713-6314-6276-6147-6099-5965-5829-5671
Percentage of BenefitsLossesAndExpenses-38.2-41.0-41.3-41.1-38.9-44.0-43.6-43.2-41.0-46.2-46.4-47.1-55.8-47.4-49.2-46.1-46.0-45.6-46.0-43.1

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value1760202118851869172219201813182617591844176017271706182617921747
Percentage of BenefitsLossesAndExpenses9.912.712.312.411.314.113.713.613.014.614.213.914.213.714.113.1

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value6843651663916175592660335760578554905805576057125714606460735973594555345689575356485144494547614426422138373787365233603035
Percentage of BenefitsLossesAndExpenses38.340.941.640.838.844.243.543.240.646.046.445.947.545.547.744.844.942.344.943.743.343.042.441.340.341.439.639.337.636.333.9

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value160771393213449133021354811697114391154611840105571043610692
Percentage of BenefitsLossesAndExpenses90.087.487.587.988.885.786.486.287.683.684.086.0

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect



Period End2020-03-312019-03-31
Value20001534
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0

us-gaap:CommonStockDividendsPerShareCashPaid



Period End2020-01-312019-10-252019-07-262019-04-262019-01-252018-10-262018-07-272018-04-272018-01-262018-03-312017-10-272017-12-312017-07-312017-09-302017-04-282017-06-302017-01-272017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value0.550.550.550.550.50.50.50.50.40.40.40.40.40.40.40.40.290.290.290.290.290.290.290.290.290.280.280.280.280.270.270.270.270.260.260.260.260.250.250.250.25
Percentage of CommonStockDividendsPerShareCashPaid100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:SubsequentEventType

us-gaap:SubsequentEvent



Period End2020-04-242019-10-252019-07-262019-04-262018-10-262018-07-272018-06-302017-12-312017-06-302016-10-28
Value0.6250.550.550.550.50.50.50.40.40.29
Percentage of CommonStockDividendsPerShareCashPaid0.0100.0100.0100.0100.0100.00.0100.0100.00.0

us-gaap:SubsequentEventType

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:SubsequentEvent



Period End2020-02-202019-04-182018-11-022018-04-192017-11-022017-04-202017-02-142016-10-262015-04-302014-10-31
Value0.6250.550.50.50.40.40.40.290.290.28
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ComprehensiveIncomeNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value36549175410627154026141713181915167031123-57942836925222298357434135263378436-68355300415181496370258535540303493428286
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType, us-gaap:VariableRate

us-gaap:DebtInstrumentBasisSpreadOnVariableRate1

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks, us-gaap:SubsequentEvent, us-gaap:LondonInterbankOfferedRateLIBOR



Period End2020-02-20
Value0.0115
Percentage of DebtInstrumentBasisSpreadOnVariableRate1100.0

us-gaap:DebtSecuritiesAvailableForSaleRealizedGain



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value5670418101106332134
Percentage of DebtSecuritiesAvailableForSaleRealizedGain100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleRealizedGainLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value4939187-2085329-1402
Percentage of DebtSecuritiesAvailableForSaleRealizedGainLoss100.0100.0100.0100.0100.00.0100.0100.0100.0100.00.0100.0

us-gaap:DebtSecuritiesAvailableForSaleRealizedLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value73123112121031532
Percentage of DebtSecuritiesAvailableForSaleRealizedLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Depreciation



Period End2020-03-312019-03-31
Value124118
Percentage of Depreciation100.0100.0

us-gaap:Dividends



Period End2020-01-312019-10-252019-07-262019-04-262019-01-252018-10-262018-07-272018-04-272018-01-262018-03-312017-10-272017-12-312017-07-312017-09-302017-04-282017-06-302017-01-272017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value7373747468696969555557575858585843434343434343434342424343424242424142414241414041
Percentage of Dividends100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:SubsequentEventType

us-gaap:SubsequentEvent



Period End2020-04-242020-01-312019-10-252019-07-262019-04-262018-10-262018-07-272018-06-302017-12-312017-06-302016-10-28
Value8373737474696969575843
Percentage of Dividends0.0100.0100.0100.0100.0100.0100.00.0100.0100.00.0

us-gaap:DividendsCommonStockCash



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value8374737475696968715658
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value8374737475696968715658
Percentage of DividendsCommonStockCash100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GoodwillAcquiredDuringPeriod



Period End2020-03-312018-03-312017-03-312014-03-312013-03-312012-03-312011-03-31
Value515479760453
Percentage of GoodwillAcquiredDuringPeriod100.0100.0100.0100.00.0100.0100.0

us-gaap:BusinessAcquisition

hum:EnclaraHealthcare



Period End2020-01-31
Value515
Percentage of GoodwillAcquiredDuringPeriod0.0

us-gaap:StatementBusinessSegments

hum:HealthcareServices



Period End2020-03-312018-03-312017-03-312013-03-31
Value51511970
Percentage of GoodwillAcquiredDuringPeriod100.024.8100.00.0

us-gaap:Retail



Period End2020-03-31
Value0.0
Percentage of GoodwillAcquiredDuringPeriod0.0

us-gaap:IncomeLossFromEquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value8-21123290000
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value8-21123290000
Percentage of IncomeLossFromEquityMethodInvestments100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:IncreaseDecreaseInBookOverdrafts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-31
Value-55-486950-17-28125-50-17-3054-61-3429-9-65-445-1321-4667-2727-13613027-44-344717-12-157
Percentage of IncreaseDecreaseInBookOverdrafts100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInContractWithCustomerLiability



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value27-27-38029-11-3336-763328-306991
Percentage of IncreaseDecreaseInContractWithCustomerLiability100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInDeferredIncomeTaxes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value3-1830021-29-469387-83-1865627-29125-7839-1515-41-305834-91326-11-398074-39-2720
Percentage of IncreaseDecreaseInDeferredIncomeTaxes100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInHealthCareInsuranceLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1086-216378-1821162-1580117293-29112177198-486-2091441385414117289-201-102346539-178-9167311-172-39284470484
Percentage of IncreaseDecreaseInHealthCareInsuranceLiabilities100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherDeposits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-12-312011-09-302011-03-31
Value574-634-462-81554-1018-11371141401-108-1503511730743129-97318688-725-382123-176-616-34722051-333-104236-50-499298-60337183
Percentage of IncreaseDecreaseInOtherDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1470216-882446102-455-7194941164213-176130415-845-259-7685-208-3572921145-84634856616557-2213017-1413811029
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1203303284-13216-1224-132-2058850324-225542810-1071-12121011-1063-1281051175-403-43684289-28-1381901797052204246
Percentage of IncreaseDecreaseInOtherOperatingLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInReceivables



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value953211-56-1063940-11-408197422-48-1508592558554-1788816576236-1143443644196-1069613524162-771272588110-259255260280
Percentage of IncreaseDecreaseInReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AwardType

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:EmployeeStockOption



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value92000.08000.0101000.067000.0130000.0-5000.0186000.0197000.0213000.0-2000.0165000.0158000.0199000.03000.0210000.0218000.0169000.0-6000.0182000.0193000.0218000.0-3000.0203000.0227000.0268000.0-19000.0289000.0349000.0384000.0-53000.0431000.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RestrictedStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value0000000000000011101110111011101
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements634.8800.0597.0670.1345.4-380.0421.0312.7335.2-900.0593.9554.4426.6-300.0608.1551.4724.3183.3766.5767.9752.8-1833.3751.2615.0480.6-431.6495.2343.0287.0-66.0312.8

us-gaap:InterestPaidNet



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value40762681297522762292
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentIncomeInterestAndDividend



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value1491501361141019611316414189104101111989695100136130113959995929197939293102969994919189877985
Percentage of InvestmentIncomeInterestAndDividend100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value9087796055575246563142404542424346676954
Percentage of InvestmentIncomeInterestAndDividend60.458.058.152.654.559.446.028.039.734.840.439.640.542.943.845.346.049.353.147.8

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value56755556767711676
Percentage of InvestmentIncomeInterestAndDividend3.44.05.14.45.05.24.43.75.06.76.76.99.96.17.36.3

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-03-312012-12-312012-09-30
Value010100111761098888770000000000000
Percentage of InvestmentIncomeInterestAndDividend0.00.70.00.90.00.09.710.44.311.28.77.97.28.28.37.47.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value545650484134353037182324
Percentage of InvestmentIncomeInterestAndDividend36.237.336.842.140.635.431.018.326.220.222.123.8

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value102051379612925129758725115321129011139777510755104091063776951108411048110287692
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value85715341416132880314951368129280213911335129382413631337
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear18.411.111.010.29.213.012.111.610.312.912.812.210.712.312.1

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value9490123551165011794803210127100019942711993219075
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear193.089.690.190.992.187.888.689.391.686.787.2

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value4280109505133595572327836191661191753451116713493576
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value502298544625133346314-125493514
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears111.726.616.010.512.98.856.511.912.88.4-0.814.314.34.319.7

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value3778804245931335272453082152115
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears188.373.484.089.587.191.230.488.185.291.696.6

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1562913689133571331813493114341124311525116801063010657108821134910921110391136511411
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value131115811448144212871443134613581273141113541312128613491358
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims18.411.510.810.89.512.612.011.810.913.312.712.111.312.412.3

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value14460122011205012023123231008310020102701055292019294
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims192.589.190.290.391.388.289.189.190.386.687.2

us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:LineOfCreditFacilityCommitmentFeePercentage

us-gaap:RevolvingCreditFacility, hum:UnsecuredRevolvingCreditAgreementExpiresMay2022, us-gaap:LineOfCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00150.00.00.00.0015
Percentage of LineOfCreditFacilityCommitmentFeePercentage100.00.00.00.0100.0

us-gaap:Range, us-gaap:CreditFacility, us-gaap:DebtInstrument, us-gaap:LongtermDebtType

srt:Maximum, us-gaap:RevolvingCreditFacility, hum:UnsecuredRevolvingCreditAgreementExpiresMay2022, us-gaap:LineOfCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00250.00.00.00.0025
Percentage of LineOfCreditFacilityCommitmentFeePercentage166.70.00.00.0166.7

srt:Minimum, us-gaap:RevolvingCreditFacility, hum:UnsecuredRevolvingCreditAgreementExpiresMay2022, us-gaap:LineOfCredit



Period End2020-03-312019-12-312019-09-302019-06-302019-03-31
Value0.00090.00.00.00.0009
Percentage of LineOfCreditFacilityCommitmentFeePercentage60.00.00.00.060.0

us-gaap:OperatingIncomeLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value1074362868111584751796186276056685811001738-438949683547289695573790371589681721-14621689765309701590416725754524648562443
Percentage of OperatingIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value425314424533353038-65-106589107-2-5414538
Percentage of OperatingIncomeLoss3.914.61.63.85.36.43.63.55.0-11.5-12.40.551.3-0.00.7-0.3-0.914.26.56.6

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value105-14645165-11818021147931011711137124
Percentage of OperatingIncomeLoss9.8-40.30.50.419.5-2.18.49.327.88.310.89.29.8-2.53.918.2

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value24218021121217215820620617321324027024426728827124124428422323014620220618513715612411866144
Percentage of OperatingIncomeLoss22.549.724.319.020.330.621.423.922.837.628.024.514.0-61.030.339.744.184.440.938.929.139.434.330.225.7-978.625.118.015.421.420.5

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value685275639856465339634493267391610607
Percentage of OperatingIncomeLoss63.876.073.676.854.965.666.057.235.169.171.155.2

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value-105-236612515151-30-22-173717538-178-225818-79-16-744-10-273468-38-13-120-58-117014109181-12
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value45271604-32329-140226312619205851289116218465136
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value35211401-21522-902162016121337321957411534384
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax100.0100.0100.0100.00.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value1060203-187-500101110772119944210312252
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax100.0100.00.0100.00.0100.0100.0100.0100.0100.00.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-30
Value-92-28716919665-42-9-203-3268838-251-911148-6625-8714-6-3656108-52-16-183-87-4116312041145127
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value-70-26712915152-32-7-151-2175524-158-67031-4216-559-3-233569-33-10-116-55-37420139281-9
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-31
Value-22020404513-10-2-52-193314-93-34117-249-325-3-132139-19-6-67-32-1421185346-5
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNonoperatingIncomeExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-29728982174-39-22-110000
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0100.0100.00.00.00.00.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-29728982174-3944-11
Percentage of OtherNonoperatingIncomeExpense100.0100.0100.0100.0100.0-200.0100.0

us-gaap:OtherOperatingActivitiesCashFlowStatement



Period End2020-03-312019-03-31
Value-1318
Percentage of OtherOperatingActivitiesCashFlowStatement100.0100.0

us-gaap:PaymentsForLossesAndLossAdjustmentExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1448513905129751348812320115891131311417113941092110528108121114611200111191137711268
Percentage of PaymentsForLossesAndLossAdjustmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value135915631424138212651500138113251265140513341318131713681351
Percentage of PaymentsForLossesAndLossAdjustmentExpense9.411.211.010.210.312.912.211.611.112.912.712.211.812.212.2

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value13268124351169212253111651017910008101871020194739190
Percentage of PaymentsForLossesAndLossAdjustmentExpense91.689.490.190.890.687.888.589.289.586.787.3

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value2459223199596021751308755913171119281129133218762033200510981430239426248928299349814615075961280602783105580271411861525
Percentage of PaymentsToAcquireAvailableForSaleSecuritiesDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:BusinessAcquisition, us-gaap:SubsequentEventType

us-gaap:PaymentsToAcquireBusinessesGross

hum:EnclaraHealthcare, us-gaap:SubsequentEvent



Period End2020-02-20
Value707
Percentage of PaymentsToAcquireBusinessesGross100.0

us-gaap:PaymentsToAcquireBusinessesNetOfCashAcquired



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value70900000018516921127061000380150-3626149759472125650
Percentage of PaymentsToAcquireBusinessesNetOfCashAcquired100.00.00.00.00.00.00.0100.0100.0100.0100.0100.0100.00.0100.0100.00.00.00.0100.00.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:PolicyholderBenefitsAndClaimsIncurredHealthCare



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-09-302011-06-302011-03-312010-09-302010-06-302010-03-31
Value156291368913357133181349311433112431153611670106391064210889113261120110900115091139711116108961125211005974996669627912482038075809181957516746776528350714672697344664168696817
Percentage of PolicyholderBenefitsAndClaimsIncurredHealthCare100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems

hum:CorporateAndEliminations



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-30
Value-146-98-141-143-121-96-132-121-121-164-187-213-196-276-224-228-212-239-244-178
Percentage of PolicyholderBenefitsAndClaimsIncurredHealthCare-0.9-0.7-1.1-1.1-0.9-0.8-1.2-1.0-1.0-1.5-1.8-2.0-1.7-2.5-2.1-2.0-1.9-2.2-2.2-1.6

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-30
Value1311158114481442128714431347135712731411135413121286135713521302
Percentage of PolicyholderBenefitsAndClaimsIncurredHealthCare8.411.510.810.89.512.612.011.810.913.312.712.011.412.112.411.3

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value144641220612050120191232710083100201027010552920192949672
Percentage of PolicyholderBenefitsAndClaimsIncurredHealthCare92.589.290.290.291.488.289.189.090.486.587.388.8

us-gaap:ProceedsFromIncomeTaxRefunds



Period End2020-03-312019-03-31
Value622
Percentage of ProceedsFromIncomeTaxRefunds100.0100.0

us-gaap:ProceedsFromIssuanceOfCommercialPaper



Period End2020-03-312019-03-312015-12-312015-09-302014-12-312014-09-30
Value19817288-29000
Percentage of ProceedsFromIssuanceOfCommercialPaper100.0100.0100.0100.00.00.0

us-gaap:ProceedsFromIssuanceOfSeniorLongTermDebt



Period End2020-03-312019-12-312019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-31
Value10900000007940-69910000000
Percentage of ProceedsFromIssuanceOfSeniorLongTermDebt100.00.00.00.00.00.00.0100.00.0100.0100.00.00.00.00.00.00.00.0

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value735452387497397157260338217192270365284344447422213184266285330183190254258224304255294386354424398433
Percentage of ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromNotesPayable



Period End2020-03-312019-03-31
Value10000
Percentage of ProceedsFromNotesPayable100.00.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks



Period End2020-03-31
Value1000
Percentage of ProceedsFromNotesPayable100.0

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-03-312011-03-312010-03-31
Value1415120825256420628802061016139274030592879599314669399142045187810425281238164889118485253662192510365242153545
Percentage of ProceedsFromSaleOfAvailableForSaleSecuritiesDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:RevenueFromContractWithCustomerIncludingAssessedTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312010-09-302010-06-302010-03-312009-12-312009-09-302009-06-302009-03-31
Value424162953933553551416838138232713189223230137621287813694140071380013361133631373213833123281223812222117121018710319103211048695579651969910219905693009284919083508424865284407633771678987711
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:MajorCustomers, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:ASOAndOther, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value195203200193194193215208
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax46.01.250.954.454.61.456.454.5

us-gaap:OperatingSegments, hum:ASOAndOther, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value43455513
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax0.90.01.01.41.40.00.30.8

us-gaap:OperatingSegments, hum:Pharmacy, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value12151534636555257
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax28.50.313.513.010.10.413.614.9

us-gaap:OperatingSegments, hum:Provider, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value10479136111120114113112
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax24.50.534.631.333.80.829.729.3

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value195203200193194193215208
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax46.01.250.954.454.61.456.454.5

us-gaap:OperatingSegments, hum:HealthcareServices



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-30
Value225130189157156169165169104878083881126568657369228315311328332311313328325315271271
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax53.10.848.144.243.91.243.344.231.80.735.936.10.60.90.50.50.50.50.51.72.32.52.72.72.73.13.23.13.02.82.8

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value43455513
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax0.90.01.01.41.40.00.30.8

us-gaap:MajorCustomers

hum:ASOAndOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value199206204198199198216213
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax46.91.351.955.856.11.456.755.8

hum:Pharmacy



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value12151534636555257
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax28.50.313.513.010.10.413.614.9

hum:Provider



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value10479136111120114113112
Percentage of RevenueFromContractWithCustomerIncludingAssessedTax24.50.534.631.333.80.829.729.3

us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesRestrictedStockAwardGross

us-gaap:CommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value0.00.00.032000.00.00.00.0
Percentage of StockIssuedDuringPeriodSharesRestrictedStockAwardGross0.00.00.0100.00.00.00.0

us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesStockOptionsExercised

us-gaap:CommonStock



Period End2020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.01000.01000.00.02000.02000.06000.013000.00.02000.0
Percentage of StockIssuedDuringPeriodSharesStockOptionsExercised0.0100.0100.00.0100.0100.0100.0100.00.0100.0

us-gaap:StockIssuedDuringPeriodValueRestrictedStockAwardGross



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value000-100022000
Percentage of StockIssuedDuringPeriodValueRestrictedStockAwardGross0.00.00.0100.00.00.00.0100.00.00.00.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-6-450-3-13-53-3-1-66-38-6
Percentage of StockIssuedDuringPeriodValueRestrictedStockAwardGross0.00.00.0300.00.00.00.0-4.50.00.00.0

us-gaap:TreasuryStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value64502135332366386
Percentage of StockIssuedDuringPeriodValueRestrictedStockAwardGross0.00.00.0-200.00.00.00.0104.50.00.00.0

us-gaap:StockIssuedDuringPeriodValueStockOptionsExercised



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value19355117-13131218
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value7132117-13131218
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised36.837.140.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TreasuryStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-09-30
Value122231200
Percentage of StockIssuedDuringPeriodValueStockOptionsExercised63.262.960.01200.00.00.0

us-gaap:SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1591313694134131332613760114701137211596119471068310742109961158010978111291146011751
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value135715661449142212711448135313581307140713671323130613531362
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense8.511.410.810.79.212.611.911.710.913.212.712.011.312.312.2

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value14698122211210512051126061011410140103301073992489346
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense92.489.290.290.491.688.289.289.189.986.687.0

us-gaap:SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value-284-5-56-8-267-36-129-71-267-53-85-5762311107-90-775340
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-4615-12016-5-70-344-13-11-20-4-4
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense16.2-300.01.8-250.0-6.013.95.4-0.012.7-7.515.31.9-8.7-0.44.4

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value-238-20-55-28-283-31-120-60-187-47-52
Percentage of SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense83.8400.098.2350.0106.086.193.084.570.088.761.2

us-gaap:TreasuryStockValueAcquiredCostMethod



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-31
Value17601000010796201425115462415603032664211810111
Percentage of TreasuryStockValueAcquiredCostMethod100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementEquityComponents

us-gaap:AdditionalPaidInCapital



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-30
Value0-2002000-15015000-200-300
Percentage of TreasuryStockValueAcquiredCostMethod0.0-333.320.00.0-1500.018.80.00.0-392.2-124.5

us-gaap:TreasuryStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value172608000160646201422511346541
Percentage of TreasuryStockValueAcquiredCostMethod100.0433.380.00.01600.081.2100.0100.0492.287.1224.5

hum:BookOverdraftLiability



Period End2020-03-312019-12-312018-12-31
Value169225171
Percentage of BookOverdraftLiability100.0100.0100.0

us-gaap:BalanceSheetLocation, us-gaap:OptionIndexedToIssuersEquityEquity

hum:FinancialAssetsFairValueDisclosure

us-gaap:OtherNoncurrentAssets, us-gaap:CallOption



Period End2020-03-312019-12-312018-12-31
Value368557246
Percentage of FinancialAssetsFairValueDisclosure100.0100.0100.0

us-gaap:ConcentrationRiskByBenchmark

hum:NetAssetLiability

hum:CmsSubsidiesOrDiscounts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value-347229-444-871-952-331-1420-2546-984
Percentage of NetAssetLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value-36-170-155-148-161-170-303-249-279
Percentage of NetAssetLiability10.4-74.234.917.016.951.421.39.828.4

us-gaap:ConcentrationRiskByBenchmark

hum:NetCurrentLiabilityAsset

hum:CmsSubsidiesOrDiscounts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value-347229-444-871-952-331-1420-2546-984
Percentage of NetCurrentLiabilityAsset100.0100.0100.0100.0100.0100.0100.0100.0100.0

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value-89-115-38-37-53-88-208-226-251
Percentage of NetCurrentLiabilityAsset25.6-50.28.64.25.626.614.68.925.5

us-gaap:ConcentrationRiskByBenchmark

hum:NetNoncurrentAssetLiability

hum:RiskCorridorSettlementsMedicarePartD



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value53-55-117-111-108-82-95-23-28
Percentage of NetNoncurrentAssetLiability100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AdditionalPaidInCapitalCommonStock



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value285728202608276327222535270726722626244526412306224625622527250224982530251524952465233024002376233322672242219021402101207920632043193819131897182517371658
Percentage of AdditionalPaidInCapitalCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForDoubtfulAccountsReceivableCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value73697373787992808796899211311811111911510110410411113713512111811810910910594948989858580755150
Percentage of AllowanceForDoubtfulAccountsReceivableCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:AssetsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value5857366750452024
Percentage of AssetsFairValueDisclosure100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value11497113711080410437
Percentage of AssetsFairValueDisclosure196.3310.1214.2515.7

us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302018-12-31
Value17354150381584912461
Percentage of AssetsFairValueDisclosure296.3410.1314.2615.7

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value24521925317453946139286252236158168381422291218308348553516503377
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value133211011
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax0.41.41.21.11.911.10.016.70.3

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1618271720003
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax6.58.210.79.83.80.00.00.01.0

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value4882845614122244
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax19.637.433.232.226.411.150.033.385.3

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1608510169213
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax65.338.839.939.739.633.3

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value163036281232333
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax6.513.714.216.122.633.350.050.011.5

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value412221
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax1.60.50.81.13.811.1

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value17181017612132732362498882971651962543641268392314151127
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value4633367220
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax26.937.530.017.69.83.30.70.80.0

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2800031418162
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax16.40.00.00.04.96.66.66.82.3

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value842352498939637
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax49.125.030.029.439.346.034.140.742.0

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value13382254
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax0.637.530.047.136.125.4

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value12001537654928
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax7.00.00.05.98.217.423.820.831.8

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value001013
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax0.00.010.00.01.61.4

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value114231116010561102451030610641103691007312104
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value11261093103010371037991686574407
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis9.99.89.810.110.19.36.65.73.4

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value834786641621510537528533455
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis7.37.06.16.14.95.05.15.33.8

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value408238673509312529593239311129465175
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis35.734.733.230.528.730.430.029.242.8

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value343836283543345931422595
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis30.132.533.533.830.524.4

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value154914331465163220962805292030453884
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis13.612.813.915.920.326.428.230.232.1

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value394353373370478419
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis3.43.23.53.64.63.9

us-gaap:AvailableForSaleSecuritiesDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value11497113711080410402102981043710100984312302
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value11497113711080410402102981043710100984312301
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value0.00.00.00.00.00.00.00.01000000.0
Percentage of AvailableForSaleSecuritiesDebtSecurities0.00.00.00.00.00.00.00.00.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value10811093103010361032985684573408
Percentage of AvailableForSaleSecuritiesDebtSecurities9.49.69.510.010.09.46.85.83.3

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value822804668638509523510517456
Percentage of AvailableForSaleSecuritiesDebtSecurities7.17.16.26.14.95.05.05.33.7

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value404639473590317629493142302028525381
Percentage of AvailableForSaleSecuritiesDebtSecurities35.234.733.230.528.630.129.929.043.7

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value359737103641352031412544
Percentage of AvailableForSaleSecuritiesDebtSecurities31.332.633.733.830.524.4

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value155314631501165921032771285729993889
Percentage of AvailableForSaleSecuritiesDebtSecurities13.512.913.915.920.426.528.330.531.6

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value398354374372479417
Percentage of AvailableForSaleSecuritiesDebtSecurities3.53.13.53.64.74.0

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring, us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value0.00.00.00.00.00.00.00.01000000.0
Percentage of AvailableForSaleSecuritiesDebtSecurities0.00.00.00.00.00.00.00.00.0

us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value11497113711080410402102981043710100984312302
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueMeasurementsRecurring, us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value10811093103010361032985684573408
Percentage of AvailableForSaleSecuritiesDebtSecurities9.49.69.510.010.09.46.85.83.3

us-gaap:FairValueMeasurementsRecurring, us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value822804668638509523510517456
Percentage of AvailableForSaleSecuritiesDebtSecurities7.17.16.26.14.95.05.05.33.7

us-gaap:FairValueMeasurementsRecurring, us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value404639473590317629493142302028525382
Percentage of AvailableForSaleSecuritiesDebtSecurities35.234.733.230.528.630.129.929.043.7

us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value359737103641352031412544
Percentage of AvailableForSaleSecuritiesDebtSecurities31.332.633.733.830.524.4

us-gaap:FairValueMeasurementsRecurring, us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value155314631501165921032771285729993889
Percentage of AvailableForSaleSecuritiesDebtSecurities13.512.913.915.920.426.528.330.531.6

us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value398354374372479417
Percentage of AvailableForSaleSecuritiesDebtSecurities3.53.13.53.64.74.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value10811093103010361032985684573408
Percentage of AvailableForSaleSecuritiesDebtSecurities9.49.69.510.010.09.46.85.83.3

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value822804668638509523510517456
Percentage of AvailableForSaleSecuritiesDebtSecurities7.17.16.26.14.95.05.05.33.7

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value404639473590317629493142302028525382
Percentage of AvailableForSaleSecuritiesDebtSecurities35.234.733.230.528.630.129.929.043.7

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value359737103641352031412544
Percentage of AvailableForSaleSecuritiesDebtSecurities31.332.633.733.830.524.4

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value155314631501165921032771285729993889
Percentage of AvailableForSaleSecuritiesDebtSecurities13.512.913.915.920.426.528.330.531.6

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value398354374372479417
Percentage of AvailableForSaleSecuritiesDebtSecurities3.53.13.53.64.74.0

us-gaap:AvailableForSaleSecuritiesDebtSecuritiesCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value1110410972104309991987610026969594649742955786228115820575957329741777387267742370417600759880887565824880908262755681418001805878827889774378647609742068726190
Percentage of AvailableForSaleSecuritiesDebtSecuritiesCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtSecuritiesNoncurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value3934064044114224114053792361274527162670242422032273205119401843187918391972194919471895180017101737177018241846183717831704171016951592156814991307
Percentage of AvailableForSaleSecuritiesDebtSecuritiesNoncurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value5857366050154553358220244990627943464564365422291712876
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-312015-12-312014-12-312013-12-31
Value5857366050154553358220244990627943464564365422291712876
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ContractWithCustomerLiabilityCurrent



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2742472743123122832943630378
Percentage of ContractWithCustomerLiabilityCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption



Period End2020-01-01
Value-2
Percentage of CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption100.0

us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings



Period End2020-01-01
Value-2
Percentage of CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption100.0

us-gaap:DebtInstrument, us-gaap:LongtermDebtType

us-gaap:DebtInstrumentFaceAmount

hum:A3.85PercentSeniorNotesDueOctober2024, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value6006006006006006006006006006006006006006006006006006006006006006000
Percentage of DebtInstrumentFaceAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0

hum:A4.500PercentSeniorNotesDueApril2025, us-gaap:SeniorNotes



Period End2020-03-31
Value600
Percentage of DebtInstrumentFaceAmount100.0

hum:A4.875PercentSeniorNotesDueApril2030, us-gaap:SeniorNotes



Period End2020-03-31
Value500
Percentage of DebtInstrumentFaceAmount83.3

hum:A4.95PercentSeniorNotesDueOctober2044, us-gaap:SeniorNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302013-12-31
Value7507507507507507507507507507507507507507507507507507507507507507507500
Percentage of DebtInstrumentFaceAmount125.0125.0125.0125.0125.0125.0125.0125.0125.0125.0125.00.0125.0125.0125.0125.0125.0125.0125.0125.0125.0125.0125.00.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks



Period End2020-02-29
Value1000
Percentage of DebtInstrumentFaceAmount0.0

us-gaap:DebtInstrument, us-gaap:ShortTermDebtType, us-gaap:SubsequentEventType

hum:TermLoanAgreementFebruary2020, us-gaap:NotesPayableToBanks, us-gaap:SubsequentEvent



Period End2020-02-20
Value1000
Percentage of DebtInstrumentFaceAmount0.0

us-gaap:FairValueByMeasurementBasis

us-gaap:DebtInstrumentFairValue

us-gaap:CarryingReportedAmountFairValueDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-31
Value64555366576547764776477447744773477247704780478047803792379237933793379438223825
Percentage of DebtInstrumentFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302014-12-31
Value68415916624651155006519148794909494451915185517950524004418641684035398640074102
Percentage of DebtInstrumentFairValue106.0110.2108.3107.1104.8108.7102.2102.8103.6108.8108.5108.3105.7105.6110.4109.9106.4105.1104.8107.2

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value190911001163198640314447287717182308
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value891607420452704015410
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger46.755.236.122.81.70.90.50.20.4

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value131365570170133742728
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger6.93.34.73.54.23.02.61.61.2

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value71015519155214861439882533804
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger37.214.116.427.836.932.430.731.034.8

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value120426954611521019
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger0.118.523.127.528.622.9

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1767520729492416481120456661
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger9.26.817.814.822.937.138.926.528.6

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0232171214153
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger0.02.11.83.65.33.4

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value855715541371328258
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value4132210000
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss48.260.028.613.31.90.00.00.00.0

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1300026521
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss15.30.00.00.03.74.43.82.41.7

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value290242463503427
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss34.10.028.626.744.446.037.941.546.6

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value02282138
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss0.040.028.653.338.927.7

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2001528361512
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss2.40.00.06.79.320.427.318.320.7

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value001012
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss0.00.014.30.01.91.5

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2173114863438911774574649371223999
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value14420196308755824480334107
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months6.61.730.979.264.118.07.44.72.7

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value19811824042372407457131
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months9.110.33.80.03.68.16.36.43.3

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value14535892619701434183520371297
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months66.951.341.22.35.931.428.328.632.4

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value6731512238255956
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months3.127.419.29.821.720.9

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value309580030809157822451590
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months14.25.10.00.02.517.724.331.539.8

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value248313425179
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months0.14.24.98.72.13.9

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value8633277614115430
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value501157220
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss5.80.033.350.071.49.21.41.30.0

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value150001813141
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss17.40.00.00.014.310.59.29.13.3

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value55211035436210
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss64.066.733.350.00.046.130.540.333.3

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1110116
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss1.233.333.30.014.321.1

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1000009293416
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss11.60.00.00.00.011.820.622.153.3

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.00.00.00.00.01000000.0
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss0.00.00.00.00.01.3

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value408222481797237552089021937088406307
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value1035627616760825864495338117
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition25.427.934.332.015.89.65.33.81.9

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value3291547970212505481484159
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition8.16.94.42.94.15.65.15.52.5

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value216374445256115562873271725702101
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition53.033.125.223.629.931.829.029.133.3

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value6851939158414071975
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition1.723.121.824.627.021.9

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value4851332072949542457269827012251
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition11.95.911.512.418.327.228.830.635.7

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value27152105239332
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition0.03.22.94.44.63.7

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value171810176121327323688
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancialInstrument

us-gaap:AssetBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value4633367220
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss26.937.530.017.69.83.30.70.80.0

us-gaap:CommercialMortgageBackedSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value2800031418162
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss16.40.00.00.04.96.66.66.82.3

us-gaap:CorporateDebtSecurities



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value842352498939637
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss49.125.030.029.439.346.034.140.742.0

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value13382254
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss0.637.530.047.136.125.4

us-gaap:NontaxableMunicipalNotes



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-31
Value12001537654928
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss7.00.00.05.98.217.423.820.831.8

us-gaap:USTreasuryAndGovernment



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value001013
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss0.00.010.00.01.61.4

us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument, us-gaap:MeasurementInputType

us-gaap:DerivativeAssetLiabilityNetMeasurementInput

us-gaap:FairValueInputsLevel3, us-gaap:OptionOnSecurities, hum:MeasurementInputSecuredCreditRate



Period End2020-03-312019-12-31
Value0.0410.022
Percentage of DerivativeAssetLiabilityNetMeasurementInput100.0100.0

us-gaap:FairValueInputsLevel3, us-gaap:OptionOnSecurities, us-gaap:MeasurementInputDiscountRate



Period End2020-03-312019-12-31
Value0.1050.1
Percentage of DerivativeAssetLiabilityNetMeasurementInput256.1454.5

us-gaap:FairValueInputsLevel3, us-gaap:OptionOnSecurities, us-gaap:MeasurementInputOptionVolatility



Period End2020-03-312019-12-31
Value0.280.198
Percentage of DerivativeAssetLiabilityNetMeasurementInput682.9900.0

us-gaap:EquityMethodInvestments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-31
Value10931063106110561048104710480
Percentage of EquityMethodInvestments100.0100.0100.0100.0100.0100.0100.00.0

us-gaap:BalanceSheetLocation, us-gaap:OptionIndexedToIssuersEquityEquity

us-gaap:FinancialLiabilitiesFairValueDisclosure

us-gaap:OtherNoncurrentLiabilities, us-gaap:PutOption



Period End2020-03-312019-12-312018-12-31
Value13728224
Percentage of FinancialLiabilitiesFairValueDisclosure100.0100.0100.0

us-gaap:FiniteLivedIntangibleAssetsAccumulatedAmortization



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value673652635618601582564548553544527509491473455437417396376356335492456428400402369341313294266247230213203190176164
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FiniteLivedIntangibleAssetsByMajorClass

hum:NoncompetesAndOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value2828282828282730292929292928282827262523223734312929262320171710
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization4.24.34.44.54.74.84.85.55.25.35.55.75.95.96.26.46.56.66.66.56.67.57.57.27.27.27.06.76.45.86.44.7

us-gaap:ContractualRights



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value4644424139373634323033313029282725242323222119181823222120191815
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization6.86.76.66.66.56.46.46.25.85.56.36.16.16.16.26.26.06.16.16.56.64.34.24.24.55.76.06.26.46.56.87.0

us-gaap:CustomerContracts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value514496481465450434419404414401388374360347333320307292278263248368349330310310287267248237215182
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization76.476.175.775.274.974.674.373.774.973.773.673.573.373.473.273.273.673.773.973.974.074.876.577.177.577.177.878.379.280.680.885.4

us-gaap:TradeNames



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value858484848483828078847775726966625854504743665449434034302521166
Percentage of FiniteLivedIntangibleAssetsAccumulatedAmortization12.612.913.213.614.014.314.514.614.115.414.614.714.714.614.514.213.913.613.313.212.813.411.811.410.810.09.28.88.07.16.02.8

us-gaap:FiniteLivedIntangibleAssetsGross



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-31
Value1069829829829829827827832829770754754753753753753753753755757754106410631057105710951093101610161025731687686648584584566563
Percentage of FiniteLivedIntangibleAssetsGross100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FiniteLivedIntangibleAssetsByMajorClass

hum:NoncompetesAndOther



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value2929292929292934323233333232323232323233345150505052525151514940
Percentage of FiniteLivedIntangibleAssetsGross2.73.53.53.53.53.53.54.13.94.24.44.44.24.24.24.24.24.24.24.44.54.84.74.74.74.74.85.05.05.06.76.2

us-gaap:ContractualRights



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value7070696970686868686851515151515151515152515151454551515151515144
Percentage of FiniteLivedIntangibleAssetsGross6.58.48.38.38.48.28.28.28.28.86.86.86.86.86.86.86.86.86.86.96.84.84.84.34.34.74.75.05.05.07.06.8

us-gaap:CustomerContracts



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value849646647647646646646646646566566566566566566566566566567567565764764764764792792725724733484429
Percentage of FiniteLivedIntangibleAssetsGross79.477.978.078.077.978.178.177.677.973.575.175.175.275.275.275.275.275.275.174.974.971.871.972.372.372.372.571.471.371.566.266.2

us-gaap:TradeNames



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302011-12-31
Value1218484848484848483104104104104104104104104104105105104198198198198200198189190190147135
Percentage of FiniteLivedIntangibleAssetsGross11.310.110.110.110.110.210.210.110.013.513.813.813.813.813.813.813.813.813.913.913.818.618.618.718.718.318.118.618.718.520.120.8

us-gaap:LiabilityForClaimsAndClaimsAdjustmentExpense



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value709060046220584260244862502050204961466849594838476145635049525851144976492247814764447546764778443238934070415740903779395839944108375438683953394034693222
Percentage of LiabilityForClaimsAndClaimsAdjustmentExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value593641623599539517574609576568561541547578598591616603
Percentage of LiabilityForClaimsAndClaimsAdjustmentExpense8.410.710.010.38.910.611.412.111.612.211.311.211.512.711.811.212.413.5

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-31
Value64975363559752435485433844374413432139634236414035073600
Percentage of LiabilityForClaimsAndClaimsAdjustmentExpense91.689.390.089.791.189.288.487.987.184.985.485.676.972.3

us-gaap:LiabilityForFuturePolicyBenefits



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value2052062112142132191961972842292328932899282728342294228822332151215421482298234922992286219922071827181019241858185117851690166315801560153014921193
Percentage of LiabilityForFuturePolicyBenefits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

us-gaap:LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount

hum:GroupAndSpecialty



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-30
Value528567530505449448490530502500490477
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value44003600350032003500290028002900
Percentage of LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredButNotReportedIBNRClaimsAmount833.3634.9660.4633.7779.5647.3571.4547.2

us-gaap:ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312014-12-312013-12-312012-12-31
Value1068687284959886777070787176777567857800
Percentage of ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.00.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value106868728495
Percentage of ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments100.0100.0100.0100.0100.0100.0

us-gaap:StatementBusinessSegments

us-gaap:Retail



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302016-12-312015-12-31
Value1068687284959886777070787685
Percentage of ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ShortTermDebtType

us-gaap:ShortTermBorrowings

hum:NotesPayableToBanksAndCommercialPaper



Period End2020-03-312019-09-302019-06-302019-03-312018-12-31
Value150029995013181295
Percentage of ShortTermBorrowings100.0100.0100.0100.0100.0

us-gaap:CommercialPaper



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312017-09-302017-06-302016-12-31
Value500300299300669645150150200300
Percentage of ShortTermBorrowings33.30.0100.031.650.849.80.00.00.00.0

us-gaap:NotesPayableToBanks



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-31
Value1000006506506500
Percentage of ShortTermBorrowings66.70.00.068.449.350.20.0

us-gaap:ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value7080615257705940492249924884488947604690
Percentage of ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, hum:GroupAndSpecialty



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-30
Value593623599539574609576561541
Percentage of ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet8.410.110.49.111.712.211.811.511.4

us-gaap:OperatingSegments, us-gaap:Retail



Period End2020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value648755295171540143394327
Percentage of ShortdurationInsuranceContractsIncurredClaimsAndAllocatedClaimAdjustmentExpenseNet91.689.989.690.988.286.7

us-gaap:TreasuryStockShares



Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-312015-12-312015-09-302015-06-302015-03-312014-12-312014-09-302014-06-302014-03-312013-12-312013-09-302013-06-302013-03-312012-12-312012-09-302012-06-302012-03-312011-12-312011-09-302011-06-302011-03-312010-12-312009-12-31
Value666666636363616060605554544949494950505048484443424240393736363230292925232119
Percentage of TreasuryStockShares100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Line plots across dimensions of each concept

us-gaap:SellingGeneralAndAdministrativeExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments


us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments


us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments


us-gaap:StockholdersEquity us-gaap:StatementEquityComponents


us-gaap:OtherAssetsCurrent us-gaap:ConcentrationRiskByBenchmark


us-gaap:Goodwill us-gaap:StatementBusinessSegments


us-gaap:IntangibleAssetsNetExcludingGoodwill us-gaap:FiniteLivedIntangibleAssetsByMajorClass


us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent us-gaap:ConcentrationRiskByBenchmark


us-gaap:LongTermDebtNoncurrent us-gaap:DebtInstrument, us-gaap:LongtermDebtType


us-gaap:StockholdersEquity us-gaap:StatementEquityComponents


us-gaap:DebtInstrumentInterestRateStatedPercentage us-gaap:DebtInstrument, us-gaap:LongtermDebtType