$HUM
HUMANA INC Stock $hum

$hum Overview Financials Valuation SEC Filings Company Website

2016 Q4 Form 10-K Financial Statement

#000004907118000014 Filed on February 16, 2018

Income Statement

Concept	2016 Q4	2016 Q3	2016 Q2
Revenue	$12.88B	$13.69B	$14.01B
YoY Change	-3.61%	2.48%	2.0%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin		$1.739B	$1.699B
YoY Change		3.02%	-6.49%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$117.0M	$117.0M	$116.0M
YoY Change	4.46%	9.35%	1.75%
% of Gross Profit
Operating Expenses	$13.32B	$1.739B	$1.699B
YoY Change	1.87%	3.02%	-6.49%
Operating Profit		$949.0M	$683.0M
YoY Change		36.55%	19.2%
Interest Expense	-$48.00M	$47.00M	$47.00M
YoY Change	4.35%	0.0%	0.0%
% of Operating Profit		4.95%	6.88%
Other Income/Expense, Net
YoY Change
Pretax Income	-$486.0M	$902.0M	$636.0M
YoY Change	-297.56%	39.2%	-19.8%
Income Tax	-$85.00M	$452.0M	$325.0M
% Of Pretax Income		50.11%	51.1%
Net Earnings	-$401.0M	$450.0M	$311.0M
YoY Change	-497.03%	43.31%	-27.84%
Net Earnings / Revenue	-3.11%	3.29%	2.22%
Basic Earnings Per Share	-$2.68	$3.01	$2.08
Diluted Earnings Per Share	-$2.68	$2.98	$2.06
COMMON SHARES
Basic Shares Outstanding		149.4M shares	149.4M shares
Diluted Shares Outstanding		150.9M shares	150.8M shares

Balance Sheet

Concept	2016 Q4	2016 Q3	2016 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$11.47B	$14.10B	$9.846B
YoY Change	16.61%	56.3%	5.97%
Cash & Equivalents	$3.877B	$6.769B	$2.429B
Short-Term Investments	$7.595B	$7.329B	$7.417B
Other Short-Term Assets	$3.438B	$4.791B	$5.337B
YoY Change	-27.04%	-16.92%	-3.92%
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$16.19B	$19.65B	$17.74B
YoY Change	3.05%	24.61%	4.48%
LONG-TERM ASSETS
Property, Plant & Equipment	$1.505B	$1.478B	$1.452B
YoY Change	8.74%	10.05%	11.78%
Goodwill	$3.272B	$3.272B	$3.266B
YoY Change	0.21%	0.18%	0.0%
Intangibles	$280.0M	$298.0M	$316.0M
YoY Change	-21.57%	-21.37%	-21.2%
Long-Term Investments	$9.798B	$9.602B	$9.468B
YoY Change	7.55%	3.23%	6.62%
Other Assets	$2.226B	$2.789B	$2.731B
YoY Change	-10.06%	37.05%	36.21%
Total Long-Term Assets	$9.206B	$9.812B	$9.500B
YoY Change	2.67%	15.12%	12.97%
TOTAL ASSETS
Total Short-Term Assets	$16.19B	$19.65B	$17.74B
Total Long-Term Assets	$9.206B	$9.812B	$9.500B
Total Assets	$25.40B	$29.47B	$27.24B
YoY Change	2.91%	21.28%	7.3%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$2.467B	$2.933B	$3.873B
YoY Change	11.53%	32.36%	17.65%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$300.0M	$300.0M	$300.0M
YoY Change	0.33%	2627.27%	0.0%
Long-Term Debt Due	$300.0M
YoY Change	0.33%
Total Short-Term Liabilities	$7.822B	$11.82B	$9.934B
YoY Change	-4.05%	52.62%	10.71%
LONG-TERM LIABILITIES
Long-Term Debt	$3.792B	$3.792B	$3.793B
YoY Change	-0.05%	-0.78%	-0.78%
Other Long-Term Liabilities	$263.0M	$279.0M	$347.0M
YoY Change	11.91%	24.0%	-2.8%
Total Long-Term Liabilities	$4.055B	$4.071B	$4.140B
YoY Change	0.65%	0.59%	-0.96%
TOTAL LIABILITIES
Total Short-Term Liabilities	$7.822B	$11.82B	$9.934B
Total Long-Term Liabilities	$4.055B	$4.071B	$4.140B
Total Liabilities	$14.71B	$18.18B	$16.36B
YoY Change	2.64%	30.4%	6.93%
SHAREHOLDERS EQUITY
Retained Earnings	$11.45B	$11.90B	$11.49B
YoY Change	3.97%	8.57%	7.51%
Common Stock	$2.595B	$2.560B	$2.535B
YoY Change	1.25%	0.47%	0.28%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.298B	$3.286B	$3.287B
YoY Change	0.18%	-0.18%	0.0%
Treasury Stock Shares	49.19M shares	49.31M shares	49.33M shares
Shareholders Equity	$10.69B	$11.29B	$10.87B
YoY Change
Total Liabilities & Shareholders Equity	$25.40B	$29.47B	$27.24B
YoY Change	2.91%	21.28%	7.3%

Cashflow Statement

Concept	2016 Q4	2016 Q3	2016 Q2
OPERATING ACTIVITIES
Net Income	-$401.0M	$450.0M	$311.0M
YoY Change	-497.03%	43.31%	-27.84%
Depreciation, Depletion And Amortization	$117.0M	$117.0M	$116.0M
YoY Change	4.46%	9.35%	1.75%
Cash From Operating Activities	-$2.773B	$4.503B	-$296.0M
YoY Change	-922.85%	336.34%	-51.32%
INVESTING ACTIVITIES
Capital Expenditures	-$132.0M	-$139.0M	-$131.0M
YoY Change	-5.04%	11.2%	-3.68%
Acquisitions
YoY Change
Other Investing Activities	-$696.0M	-$98.00M	$262.0M
YoY Change	340.51%	-79.58%	-81.96%
Cash From Investing Activities	-$828.0M	-$237.0M	$131.0M
YoY Change	178.79%	-60.83%	-90.05%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	709.0M	74.00M	-207.0M
YoY Change	-24.09%	-106.85%	-48.76%
NET CHANGE
Cash From Operating Activities	-2.773B	4.503B	-296.0M
Cash From Investing Activities	-828.0M	-237.0M	131.0M
Cash From Financing Activities	709.0M	74.00M	-207.0M
Net Change In Cash	-2.892B	4.340B	-372.0M
YoY Change	-396.92%	-764.62%	-222.37%
FREE CASH FLOW
Cash From Operating Activities	-$2.773B	$4.503B	-$296.0M
Capital Expenditures	-$132.0M	-$139.0M	-$131.0M
Free Cash Flow	-$2.641B	$4.642B	-$165.0M
YoY Change	-654.83%	301.21%	-65.04%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2017	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2017
CY2017	dei	Document Period End Date DocumentPeriodEndDate	2017-12-31
CY2017	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2017	dei	Trading Symbol TradingSymbol	HUM
CY2017	dei	Amendment Flag AmendmentFlag	false
CY2017	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2017	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2017	dei	Document Type DocumentType	10-K
CY2017	dei	Entity Central Index Key EntityCentralIndexKey	0000049071
CY2018Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	137684326	shares
CY2017	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2017	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2017Q2	dei	Entity Public Float EntityPublicFloat	34733751307	USD
CY2017	dei	Entity Registrant Name EntityRegistrantName	HUMANA INC
CY2017	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2016Q4	hum	Accrued Pharmaceutical Rebates Current AccruedPharmaceuticalRebatesCurrent	889000000	USD
CY2017Q4	hum	Accrued Pharmaceutical Rebates Current AccruedPharmaceuticalRebatesCurrent	1200000000	USD
CY2016	hum	Adjustment To Future Policy Benefits Assuming Unrealized Gains On Investments Realized And Reinvested At Current Yields AdjustmentToFuturePolicyBenefitsAssumingUnrealizedGainsOnInvestmentsRealizedAndReinvestedAtCurrentYields	77000000	USD
CY2017	hum	Adjustment To Future Policy Benefits Assuming Unrealized Gains On Investments Realized And Reinvested At Current Yields AdjustmentToFuturePolicyBenefitsAssumingUnrealizedGainsOnInvestmentsRealizedAndReinvestedAtCurrentYields	168000000	USD
CY2017	hum	Amount Held In Cash And Securities In Trust At Least Equal To Recoverable From Reinsurer AmountHeldInCashAndSecuritiesInTrustAtLeastEqualToRecoverableFromReinsurer	87000000	USD
CY2017Q4	hum	Availableforsale Securitiesin Unrealized Loss Positions Qualitative Disclosure Numberof Position In Loss AvailableforsaleSecuritiesinUnrealizedLossPositionsQualitativeDisclosureNumberofPositionInLoss	900	position
CY2015	hum	Benefit Expenses Associated With Military Services And Provisions Associated With Future Policy Benefits BenefitExpensesAssociatedWithMilitaryServicesAndProvisionsAssociatedWithFuturePolicyBenefits	108000000	USD
CY2016	hum	Benefit Expenses Associated With Military Services And Provisions Associated With Future Policy Benefits BenefitExpensesAssociatedWithMilitaryServicesAndProvisionsAssociatedWithFuturePolicyBenefits	271000000	USD
CY2017	hum	Benefit Expenses Associated With Military Services And Provisions Associated With Future Policy Benefits BenefitExpensesAssociatedWithMilitaryServicesAndProvisionsAssociatedWithFuturePolicyBenefits	-22000000	USD
CY2017Q4	hum	Closing Stock Price ClosingStockPrice	248.07
CY2017	hum	Combination Of Age And Years Necessary For Retirement Provision As Related To Our Equity Award Program CombinationOfAgeAndYearsNecessaryForRetirementProvisionAsRelatedToOurEquityAwardProgram	P65Y
CY2017	hum	Consumer Discounts On Brand Name Prescription Drugs ConsumerDiscountsOnBrandNamePrescriptionDrugs	0.5
CY2016Q4	hum	Deferred Tax Assets Deferred Policy Acquisition Cost DeferredTaxAssetsDeferredPolicyAcquisitionCost	72000000	USD
CY2017Q4	hum	Deferred Tax Assets Deferred Policy Acquisition Cost DeferredTaxAssetsDeferredPolicyAcquisitionCost	48000000	USD
CY2016Q4	hum	Deferred Tax Assets Future Policy Benefits Payable DeferredTaxAssetsFuturePolicyBenefitsPayable	355000000	USD
CY2017Q4	hum	Deferred Tax Assets Future Policy Benefits Payable DeferredTaxAssetsFuturePolicyBenefitsPayable	231000000	USD
CY2016Q4	hum	Deferred Tax Liabilities Depreciable Property And Intangible Assets DeferredTaxLiabilitiesDepreciablePropertyAndIntangibleAssets	363000000	USD
CY2017Q4	hum	Deferred Tax Liabilities Depreciable Property And Intangible Assets DeferredTaxLiabilitiesDepreciablePropertyAndIntangibleAssets	237000000	USD
CY2015	hum	Depreciation And Amortization Classified As Benefit Expense DepreciationAndAmortizationClassifiedAsBenefitExpense	92000000	USD
CY2016	hum	Depreciation And Amortization Classified As Benefit Expense DepreciationAndAmortizationClassifiedAsBenefitExpense	111000000	USD
CY2017	hum	Depreciation And Amortization Classified As Benefit Expense DepreciationAndAmortizationClassifiedAsBenefitExpense	107000000	USD
CY2015	hum	Depreciation And Amortization Income Statement DepreciationAndAmortizationIncomeStatement	355000000	USD
CY2016	hum	Depreciation And Amortization Income Statement DepreciationAndAmortizationIncomeStatement	354000000	USD
CY2017	hum	Depreciation And Amortization Income Statement DepreciationAndAmortizationIncomeStatement	378000000	USD
CY2017	hum	Dividends To Parent Without Prior State Regulatory Approval DividendsToParentWithoutPriorStateRegulatoryApproval	1400000000	USD
CY2015	hum	Effective Income Tax Rate Reconciliation Health Insurer Fee Amount EffectiveIncomeTaxRateReconciliationHealthInsurerFeeAmount	314000000	USD
CY2016	hum	Effective Income Tax Rate Reconciliation Health Insurer Fee Amount EffectiveIncomeTaxRateReconciliationHealthInsurerFeeAmount	336000000	USD
CY2017	hum	Effective Income Tax Rate Reconciliation Health Insurer Fee Amount EffectiveIncomeTaxRateReconciliationHealthInsurerFeeAmount	0	USD
CY2015	hum	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options And Restricted Stock Vesting EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptionsAndRestrictedStockVesting	34000000	USD
CY2016	hum	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options And Restricted Stock Vesting EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptionsAndRestrictedStockVesting	53000000	USD
CY2017	hum	Employee Service Share Based Compensation Tax Benefit Realized From Exercise Of Stock Options And Restricted Stock Vesting EmployeeServiceShareBasedCompensationTaxBenefitRealizedFromExerciseOfStockOptionsAndRestrictedStockVesting	68000000	USD
CY2017	hum	Estimated Charges Per Diluted Share EstimatedChargesPerDilutedShare	0.64
CY2015	hum	Favorable Medical Claims Reserve Development Related To Prior Fiscal Years FavorableMedicalClaimsReserveDevelopmentRelatedToPriorFiscalYears	236000000	USD
CY2016	hum	Favorable Medical Claims Reserve Development Related To Prior Fiscal Years FavorableMedicalClaimsReserveDevelopmentRelatedToPriorFiscalYears	582000000	USD
CY2017	hum	Favorable Medical Claims Reserve Development Related To Prior Fiscal Years FavorableMedicalClaimsReserveDevelopmentRelatedToPriorFiscalYears	483000000	USD
CY2017Q4	hum	Gain Contingency Recovery Sought GainContingencyRecoverySought	611000000	USD
CY2017	hum	General Obligation Bonds As Percentage Of Tax Exempt Municipal Securities That Were Not Pre Refunded GeneralObligationBondsAsPercentageOfTaxExemptMunicipalSecuritiesThatWereNotPreRefunded	0.49
CY2015	hum	Government And Health Plan Member Subsidies Amount GovernmentAndHealthPlanMemberSubsidiesAmount	12300000000	USD
CY2016	hum	Government And Health Plan Member Subsidies Amount GovernmentAndHealthPlanMemberSubsidiesAmount	13400000000	USD
CY2017	hum	Government And Health Plan Member Subsidies Amount GovernmentAndHealthPlanMemberSubsidiesAmount	13500000000	USD
CY2015	hum	Health Care Cost Payments HealthCareCostPayments	3300000000	USD
CY2016	hum	Health Care Cost Payments HealthCareCostPayments	3300000000	USD
CY2017	hum	Health Care Cost Payments HealthCareCostPayments	3400000000	USD
CY2016	hum	Health Care Reform Premium Deficiency Current Period Results Increase Decrease In Pdr Liability HealthCareReformPremiumDeficiencyCurrentPeriodResultsIncreaseDecreaseInPDRLiability	-384000000	USD
CY2015Q4	hum	Health Care Reform Premium Deficiency Reserve HealthCareReformPremiumDeficiencyReserve	176000000	USD
CY2016Q2	hum	Health Care Reform Premium Deficiency Reserve Change In Estimate HealthCareReformPremiumDeficiencyReserveChangeInEstimate	208000000	USD
CY2014Q4	hum	Health Care Reform Provisionfor Premium Deficiency HealthCareReformProvisionforPremiumDeficiency	0	USD
CY2015Q4	hum	Health Care Reform Provisionfor Premium Deficiency HealthCareReformProvisionforPremiumDeficiency	176000000	USD
CY2016Q4	hum	Health Care Reform Provisionfor Premium Deficiency HealthCareReformProvisionforPremiumDeficiency	0	USD
CY2017Q4	hum	Health Care Reform Provisionfor Premium Deficiency HealthCareReformProvisionforPremiumDeficiency	0	USD
CY2017Q4	hum	Health Care Reform Provisionfor Premium Deficiency HealthCareReformProvisionforPremiumDeficiency	0	USD
CY2015	hum	Health Care Reform Provisionfor Premium Deficiency1 HealthCareReformProvisionforPremiumDeficiency1	176000000	USD
CY2016	hum	Health Care Reform Provisionfor Premium Deficiency1 HealthCareReformProvisionforPremiumDeficiency1	-176000000	USD
CY2017	hum	Health Care Reform Provisionfor Premium Deficiency1 HealthCareReformProvisionforPremiumDeficiency1	0	USD
CY2016Q4	hum	Increase To Future Policy Benefits Payable IncreaseToFuturePolicyBenefitsPayable	659000000	USD
CY2016Q4	hum	Increase To Reinsurance Recoverable IncreaseToReinsuranceRecoverable	154000000	USD
CY2016Q4	hum	Long Term Insurance Reserve Strengthening Expense LongTermInsuranceReserveStrengtheningExpense	505000000	USD
CY2016Q4	hum	Long Term Insurance Reserve Strengthening Expense Net Of Tax LongTermInsuranceReserveStrengtheningExpenseNetOfTax	318000000	USD
CY2016Q4	hum	Long Term Insurance Reserve Strengthening Expense Per Diluted Share LongTermInsuranceReserveStrengtheningExpensePerDilutedShare	2.11
CY2017	hum	Maximum Carrying Value Of Reinsurance Recoverables For Number Of Reinsurers MaximumCarryingValueOfReinsuranceRecoverablesForNumberOfReinsurers	71000000	USD
CY2015	hum	Maximum Deductibility Of Annual Compensation Per Employee As Mandated By Health Reforms MaximumDeductibilityOfAnnualCompensationPerEmployeeAsMandatedByHealthReforms	500000	USD
CY2016	hum	Maximum Deductibility Of Annual Compensation Per Employee As Mandated By Health Reforms MaximumDeductibilityOfAnnualCompensationPerEmployeeAsMandatedByHealthReforms	500000	USD
CY2017	hum	Maximum Deductibility Of Annual Compensation Per Employee As Mandated By Health Reforms MaximumDeductibilityOfAnnualCompensationPerEmployeeAsMandatedByHealthReforms	500000	USD
CY2017	hum	Maximum Percentage Of Any General Obligation Bonds In One State MaximumPercentageOfAnyGeneralObligationBondsInOneState	0.09
CY2015	hum	Merger Termination Fee And Related Costs Net MergerTerminationFeeAndRelatedCostsNet	23000000	USD
CY2016	hum	Merger Termination Fee And Related Costs Net MergerTerminationFeeAndRelatedCostsNet	104000000	USD
CY2017	hum	Merger Termination Fee And Related Costs Net MergerTerminationFeeAndRelatedCostsNet	-936000000	USD
CY2015	hum	Military Services Benefit Expense Benefit MilitaryServicesBenefitExpenseBenefit	12000000	USD
CY2016	hum	Military Services Benefit Expense Benefit MilitaryServicesBenefitExpenseBenefit	8000000	USD
CY2017	hum	Military Services Benefit Expense Benefit MilitaryServicesBenefitExpenseBenefit	0	USD
CY2017	hum	Minimum Age Required For Retirement Eligibility As Related To Our Equity Award Program MinimumAgeRequiredForRetirementEligibilityAsRelatedToOurEquityAwardProgram	P55Y
CY2017	hum	Minimum Number Of Years Of Service For Retirement Eligibility As Related To Our Equity Award Program MinimumNumberOfYearsOfServiceForRetirementEligibilityAsRelatedToOurEquityAwardProgram	P5Y
CY2017Q4	hum	Net Operating Lease Commitment Thereafter NetOperatingLeaseCommitmentThereafter	1000000	USD
CY2016Q4	hum	Mortgagebacked Securitiesas Percentageof Agency Mortgagebacked Securities MortgagebackedSecuritiesasPercentageofAgencyMortgagebackedSecurities	0.99
CY2017Q4	hum	Mortgagebacked Securitiesas Percentageof Agency Mortgagebacked Securities MortgagebackedSecuritiesasPercentageofAgencyMortgagebackedSecurities	0.93
CY2016Q4	hum	Net Asset Liability Deferred Acquisition Cost NetAssetLiabilityDeferredAcquisitionCost	119000000	USD
CY2017Q4	hum	Net Asset Liability Deferred Acquisition Cost NetAssetLiabilityDeferredAcquisitionCost	103000000	USD
CY2016Q4	hum	Net Asset Liability Future Policy Benefits Payable NetAssetLiabilityFuturePolicyBenefitsPayable	2896000000	USD
CY2017Q4	hum	Net Asset Liability Future Policy Benefits Payable NetAssetLiabilityFuturePolicyBenefitsPayable	2979000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Total NetOperatingLeaseCommitmentTotal	416000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Within Year Five NetOperatingLeaseCommitmentWithinYearFive	32000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Within Year Four NetOperatingLeaseCommitmentWithinYearFour	50000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Within Year One NetOperatingLeaseCommitmentWithinYearOne	138000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Within Year Three NetOperatingLeaseCommitmentWithinYearThree	79000000	USD
CY2017Q4	hum	Net Operating Lease Commitment Within Year Two NetOperatingLeaseCommitmentWithinYearTwo	116000000	USD
CY2017	hum	Number Of Days Notice For Employer Group To Cancel Short Duration Prepaid Health Services Policies NumberOfDaysNoticeForEmployerGroupToCancelShortDurationPrepaidHealthServicesPolicies	P30D
CY2014Q2	hum	Number Of Matters Related To Notice Of Non Intervention NumberOfMattersRelatedToNoticeOfNonIntervention	1	matter
CY2012Q1	hum	Number Of Medical Providers Questioned NumberOfMedicalProvidersQuestioned	1	provider
CY2017	hum	Number Of Reinsurers Comprising Other Reinsurance Recoverables Balance NumberOfReinsurersComprisingOtherReinsuranceRecoverablesBalance	18	Reinsurer
CY2017Q4	hum	Number Of Reinsurers Who Have Placed Cash And Securities In Trusts NumberOfReinsurersWhoHavePlacedCashAndSecuritiesInTrusts	3	Reinsurer
CY2017Q4	hum	Number Of Shares Of Our Common Stock Reserved For Issuance Under Our Defined Contribution Retirement Savings Plans NumberOfSharesOfOurCommonStockReservedForIssuanceUnderOurDefinedContributionRetirementSavingsPlans	2400000	shares
CY2015	hum	Operating Lease Rental Expenses Net OperatingLeaseRentalExpensesNet	176000000	USD
CY2016	hum	Operating Lease Rental Expenses Net OperatingLeaseRentalExpensesNet	153000000	USD
CY2017	hum	Operating Lease Rental Expenses Net OperatingLeaseRentalExpensesNet	171000000	USD
CY2016Q4	hum	Other Long Term Assets Deferred Acquisition Costs OtherLongTermAssetsDeferredAcquisitionCosts	119000000	USD
CY2017Q4	hum	Other Long Term Assets Deferred Acquisition Costs OtherLongTermAssetsDeferredAcquisitionCosts	103000000	USD
CY2016Q4	hum	Other Long Term Assets Future Policy Benefits Payable OtherLongTermAssetsFuturePolicyBenefitsPayable	0	USD
CY2017Q4	hum	Other Long Term Assets Future Policy Benefits Payable OtherLongTermAssetsFuturePolicyBenefitsPayable	0	USD
CY2016Q4	hum	Other Long Term Liabilities Deferred Acquisition Cost OtherLongTermLiabilitiesDeferredAcquisitionCost	0	USD
CY2017Q4	hum	Other Long Term Liabilities Deferred Acquisition Cost OtherLongTermLiabilitiesDeferredAcquisitionCost	0	USD
CY2017	hum	Percent Of Consolidated Premiums And Services Revenues Related To Long Duration Insurance Products PercentOfConsolidatedPremiumsAndServicesRevenuesRelatedToLongDurationInsuranceProducts	0.01
CY2017Q4	hum	Percentage Of Collateral Related To Prime Loan PercentageOfCollateralRelatedToPrimeLoan	0.99
CY2016Q4	hum	Percentage Of Corporate Securities Associated With Financial Services Industry PercentageOfCorporateSecuritiesAssociatedWithFinancialServicesIndustry	0.23
CY2017Q4	hum	Percentage Of Corporate Securities Associated With Financial Services Industry PercentageOfCorporateSecuritiesAssociatedWithFinancialServicesIndustry	0.30
CY2017	hum	Percentage Of Retirement And Savings Plan S Assets Invested In Our Common Stock As Compared To Company S Outstanding Shares At Year End PercentageOfRetirementAndSavingsPlanSAssetsInvestedInOurCommonStockAsComparedToCompanySOutstandingSharesAtYearEnd	0.02
CY2017	hum	Percentage Of Retirement And Savings Plan S Assets Invested In Our Company Common Stock PercentageOfRetirementAndSavingsPlanSAssetsInvestedInOurCompanyCommonStock	0.11
CY2017Q4	hum	Percentage Of Tax Exempt Securities PercentageOfTaxExemptSecurities	0.02
CY2017Q4	hum	Percentage Of Tax Exempt To Municipal Securities Classified As Pre Refunded PercentageOfTaxExemptToMunicipalSecuritiesClassifiedAsPreRefunded	0.06
CY2017Q4	hum	Percentage Of Total Debt Securities PercentageOfTotalDebtSecurities	0.98
CY2015	hum	Percentage Of Total Premium And Services Revenues Derived From Contracts With Federal Government PercentageOfTotalPremiumAndServicesRevenuesDerivedFromContractsWithFederalGovernment	0.73
CY2016	hum	Percentage Of Total Premium And Services Revenues Derived From Contracts With Federal Government PercentageOfTotalPremiumAndServicesRevenuesDerivedFromContractsWithFederalGovernment	0.75
CY2017	hum	Percentage Of Total Premium And Services Revenues Derived From Contracts With Federal Government PercentageOfTotalPremiumAndServicesRevenuesDerivedFromContractsWithFederalGovernment	0.79
CY2016Q4	hum	Premiums Reduction Write Off Of Risk Corridor Receivables PremiumsReductionWriteOffOfRiskCorridorReceivables	583000000	USD
CY2016	hum	Premiums Reduction Write Off Of Risk Corridor Receivables Net Of Tax PremiumsReductionWriteOffOfRiskCorridorReceivablesNetOfTax	367000000	USD
CY2016	hum	Premiums Reduction Write Off Of Risk Corridor Receivables Per Diluted Share PremiumsReductionWriteOffOfRiskCorridorReceivablesPerDilutedShare	2.43
CY2016	hum	Proceeds From Risk Corridor Settlements ProceedsFromRiskCorridorSettlements	383000000	USD
CY2015	hum	Proceeds From Stock Options Exercised And Other ProceedsFromStockOptionsExercisedAndOther	21000000	USD
CY2016	hum	Proceeds From Stock Options Exercised And Other ProceedsFromStockOptionsExercisedAndOther	11000000	USD
CY2017	hum	Proceeds From Stock Options Exercised And Other ProceedsFromStockOptionsExercisedAndOther	62000000	USD
CY2017	hum	Restructuring And Related Cost Expected Number Of Positions Eliminated Period Percent RestructuringAndRelatedCostExpectedNumberOfPositionsEliminatedPeriodPercent	0.078
CY2015	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Shares ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares	300000	shares
CY2016	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Shares ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares	600000	shares
CY2017	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Shares ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsShares	500000	shares
CY2015	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Value ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue	56000000	USD
CY2016	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Value ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue	104000000	USD
CY2017	hum	Share Repurchases Related To Employee Stock Based Compensation Awards Value ShareRepurchasesRelatedToEmployeeStockBasedCompensationAwardsValue	115000000	USD
CY2017	us-gaap	Adjustment For Amortization AdjustmentForAmortization	75000000	USD
CY2015	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	109000000	USD
CY2016	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	115000000	USD
CY2017Q4	hum	Shares Of Retirement And Savings Plans Invested In Our Companys Common Stock SharesOfRetirementAndSavingsPlansInvestedInOurCompanysCommonStock	2000000	shares
CY2017	hum	Special Revenue Bonds As Percentage Of Tax Exempt Municipal Securities That Were Not Pre Refunded SpecialRevenueBondsAsPercentageOfTaxExemptMunicipalSecuritiesThatWereNotPreRefunded	0.51
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CY2017Q4	hum	Trade Accounts Payable And Accrued Expenses Deferred Acquisition Cost TradeAccountsPayableAndAccruedExpensesDeferredAcquisitionCost	0	USD
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CY2017Q4	hum	Trade Accounts Payable And Accrued Expenses Future Policy Benefits Payable TradeAccountsPayableAndAccruedExpensesFuturePolicyBenefitsPayable	56000000	USD
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CY2017Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1976000000	USD
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CY2016Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	168000000	USD
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CY2017Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	88000000	USD
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CY2015	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	15000000	USD
CY2016	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	0	USD
CY2017	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	0	USD
CY2015	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-1000000	USD
CY2016	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	0	USD
CY2015	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	USD
CY2016	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	USD
CY2015	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	USD
CY2016	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	USD
CY2015	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	20000000	USD
CY2015	us-gaap	Fair Value Of Assets Acquired FairValueOfAssetsAcquired	38000000	USD
CY2017Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	1000000	USD
CY2016	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	3000000	USD
CY2015	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2016	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	4000000	USD
CY2017	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	3000000	USD
CY2014Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	32000000	USD
CY2015Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	11000000	USD
CY2016Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	7000000	USD
CY2016	us-gaap	Fair Value Of Assets Acquired FairValueOfAssetsAcquired	7000000	USD
CY2017	us-gaap	Fair Value Of Assets Acquired FairValueOfAssetsAcquired	31000000	USD
CY2017	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P9Y8M12D
CY2016Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	473000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	544000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	64000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	16000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	19000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	52000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	54000000	USD
CY2016Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	753000000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	770000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions FutureMinimumSubleaseRentalsSaleLeasebackTransactions	103000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Thereafter FutureMinimumSubleaseRentalsSaleLeasebackTransactionsThereafter	51000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Within Five Years FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinFiveYears	7000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Within Four Years FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinFourYears	8000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Within One Year FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinOneYear	14000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Within Three Years FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinThreeYears	10000000	USD
CY2017Q4	us-gaap	Future Minimum Sublease Rentals Sale Leaseback Transactions Within Two Years FutureMinimumSubleaseRentalsSaleLeasebackTransactionsWithinTwoYears	13000000	USD
CY2015	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	270000000	USD
CY2016	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2017	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2015Q4	us-gaap	Goodwill Goodwill	3265000000	USD
CY2016Q4	us-gaap	Goodwill Goodwill	3272000000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	3281000000	USD
CY2016	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	7000000	USD
CY2017	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	9000000	USD
CY2015	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2016	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2017	us-gaap	Impairment Of Investments ImpairmentOfInvestments	0	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2431000000	USD
CY2016Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	500000000	USD
CY2016Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	636000000	USD
CY2016Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	902000000	USD
CY2016Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-486000000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1552000000	USD
CY2017Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1689000000	USD
CY2017Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1042000000	USD
CY2017Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	799000000	USD
CY2017Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	490000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	4020000000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1155000000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	938000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1572000000	USD
CY2015	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2016	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2017	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	133000000	USD
CY2015	us-gaap	Income Tax Reconciliation Disposition Of Business IncomeTaxReconciliationDispositionOfBusiness	-67000000	USD
CY2016	us-gaap	Income Tax Reconciliation Disposition Of Business IncomeTaxReconciliationDispositionOfBusiness	0	USD
CY2017	us-gaap	Income Tax Reconciliation Disposition Of Business IncomeTaxReconciliationDispositionOfBusiness	0	USD
CY2015	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	851000000	USD
CY2016	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	543000000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	1407000000	USD
CY2015	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	18000000	USD
CY2016	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	30000000	USD
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	36000000	USD
CY2015	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	19000000	USD
CY2016	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	8000000	USD
CY2017	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-62000000	USD
CY2015	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	44000000	USD
CY2016	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	41000000	USD
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	80000000	USD
CY2015	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	24000000	USD
CY2016	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	20000000	USD
CY2017	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	22000000	USD
CY2015	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1179000000	USD
CY2016	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	916000000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1498000000	USD
CY2015	us-gaap	Increase Decrease In Book Overdrafts IncreaseDecreaseInBookOverdrafts	-33000000	USD
CY2016	us-gaap	Increase Decrease In Book Overdrafts IncreaseDecreaseInBookOverdrafts	-89000000	USD
CY2017	us-gaap	Increase Decrease In Book Overdrafts IncreaseDecreaseInBookOverdrafts	-71000000	USD
CY2015	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	2000000	USD
CY2016	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	71000000	USD
CY2017	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-132000000	USD
CY2015	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	3000000	USD
CY2016	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	-84000000	USD
CY2017	us-gaap	Increase Decrease In Deferred Revenue IncreaseDecreaseInDeferredRevenue	98000000	USD
CY2015	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	501000000	USD
CY2016	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	-413000000	USD
CY2017	us-gaap	Increase Decrease In Health Care Insurance Liabilities IncreaseDecreaseInHealthCareInsuranceLiabilities	105000000	USD
CY2015	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	-296000000	USD
CY2016	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	1093000000	USD
CY2017	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	1823000000	USD
CY2015	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	872000000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-426000000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	582000000	USD
CY2015	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-70000000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-162000000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-155000000	USD
CY2015	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-129000000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	937000000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	641000000	USD
CY2015	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	180000000	USD
CY2016	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	158000000	USD
CY2017	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-406000000	USD
CY2016Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	280000000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	226000000	USD
CY2015	us-gaap	Interest Expense InterestExpense	186000000	USD
CY2016	us-gaap	Interest Expense InterestExpense	189000000	USD
CY2017	us-gaap	Interest Expense InterestExpense	242000000	USD
CY2015	us-gaap	Interest Paid InterestPaid	187000000	USD
CY2016	us-gaap	Interest Paid InterestPaid	185000000	USD
CY2017	us-gaap	Interest Paid InterestPaid	216000000	USD
CY2015	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	474000000	USD
CY2016	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	389000000	USD
CY2017	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	405000000	USD
CY2016Q4	us-gaap	Land Land	20000000	USD
CY2017Q4	us-gaap	Land Land	20000000	USD
CY2015	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	201000000	USD
CY2016	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	179000000	USD
CY2017	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	204000000	USD
CY2016Q4	us-gaap	Liabilities Liabilities	14711000000	USD
CY2017Q4	us-gaap	Liabilities Liabilities	17336000000	USD
CY2016Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	25396000000	USD
CY2017Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	27178000000	USD
CY2015	us-gaap	Liabilities Assumed1 LiabilitiesAssumed1	0	USD
CY2016	us-gaap	Liabilities Assumed1 LiabilitiesAssumed1	0	USD
CY2017	us-gaap	Liabilities Assumed1 LiabilitiesAssumed1	0	USD
CY2016Q4	us-gaap	Liabilities Current LiabilitiesCurrent	7822000000	USD
CY2017Q4	us-gaap	Liabilities Current LiabilitiesCurrent	9406000000	USD
CY2014Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4475000000	USD
CY2015Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4976000000	USD
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4563000000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4668000000	USD
CY2016Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	2834000000	USD
CY2017Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	2923000000	USD
CY2015	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	-80000000	USD
CY2015Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	4715000000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	4487000000	USD
CY2017Q4	us-gaap	Line Of Credit LineOfCredit	0	USD
CY2016	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	439000000	USD
CY2017	us-gaap	Liability For Future Policy Benefits Period Expense LiabilityForFuturePolicyBenefitsPeriodExpense	-22000000	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	39802000000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	40852000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	39496000000	USD
CY2017Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	2000000000	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4041000000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	4112000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	3911000000	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	44161000000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	44736000000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	43518000000	USD
CY2014Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	4397000000	USD
CY2016Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3792000000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	4770000000	USD
CY2016Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	750000000	USD
CY2017Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	824000000	USD
CY2015	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-552000000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	732000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-945000000	USD
CY2015	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	320000000	USD
CY2016	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1362000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2941000000	USD
CY2015	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	868000000	USD
CY2016	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1936000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	4051000000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	1276000000	USD
CY2016Q1	us-gaap	Net Income Loss NetIncomeLoss	254000000	USD
CY2016Q2	us-gaap	Net Income Loss NetIncomeLoss	311000000	USD
CY2016Q3	us-gaap	Net Income Loss NetIncomeLoss	450000000	USD
CY2016Q4	us-gaap	Net Income Loss NetIncomeLoss	-401000000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	614000000	USD
CY2017Q1	us-gaap	Net Income Loss NetIncomeLoss	1115000000	USD
CY2017Q2	us-gaap	Net Income Loss NetIncomeLoss	650000000	USD
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	499000000	USD
CY2017Q4	us-gaap	Net Income Loss NetIncomeLoss	184000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	2448000000	USD
CY2017	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	4	Segment
CY2015	us-gaap	Operating Income Loss OperatingIncomeLoss	2347000000	USD
CY2016	us-gaap	Operating Income Loss OperatingIncomeLoss	1741000000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	4262000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	519000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	152000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	39000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	58000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	89000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	129000000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	52000000	USD
CY2015	us-gaap	Operating Leases Income Statement Sublease Revenue OperatingLeasesIncomeStatementSubleaseRevenue	25000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	85000000	USD
CY2016	us-gaap	Operating Leases Income Statement Sublease Revenue OperatingLeasesIncomeStatementSubleaseRevenue	26000000	USD
CY2017	us-gaap	Operating Leases Income Statement Sublease Revenue OperatingLeasesIncomeStatementSubleaseRevenue	33000000	USD
CY2017Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	168000000	USD
CY2016Q4	us-gaap	Other Assets Current OtherAssetsCurrent	3438000000	USD
CY2017Q4	us-gaap	Other Assets Current OtherAssetsCurrent	2949000000	USD
CY2016Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	2226000000	USD
CY2017Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	2166000000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-165000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-124000000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	146000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	96000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	14000000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	93000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	61000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	9000000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	53000000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	35000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	5000000	USD
CY2015	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-114000000	USD
CY2016	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-101000000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	149000000	USD
CY2015	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-72000000	USD
CY2016	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-63000000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	94000000	USD
CY2015	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-42000000	USD
CY2016	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-38000000	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	55000000	USD
CY2016Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	263000000	USD
CY2017Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	237000000	USD
CY2016Q4	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	212000000	USD
CY2017Q4	us-gaap	Other Short Term Borrowings OtherShortTermBorrowings	141000000	USD
CY2015	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	43843000000	USD
CY2016	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	44964000000	USD
CY2017	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	43407000000	USD
CY2015	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	385000000	USD
CY2016	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	104000000	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	3365000000	USD
CY2015	us-gaap	Payments Of Dividends PaymentsOfDividends	172000000	USD
CY2016	us-gaap	Payments Of Dividends PaymentsOfDividends	177000000	USD
CY2017	us-gaap	Payments Of Dividends PaymentsOfDividends	220000000	USD
CY2015	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	6739000000	USD
CY2016	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	6566000000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	6265000000	USD
CY2015	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	38000000	USD
CY2016	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	7000000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	31000000	USD
CY2015	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	523000000	USD
CY2016	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	527000000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	526000000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Health Care PolicyholderBenefitsAndClaimsIncurredHealthCare	44269000000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Health Care PolicyholderBenefitsAndClaimsIncurredHealthCare	45007000000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Health Care PolicyholderBenefitsAndClaimsIncurredHealthCare	43496000000	USD
CY2016Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2017Q4	us-gaap	Preferred Stock Par Or Stated Value Per Share PreferredStockParOrStatedValuePerShare	1
CY2016Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	10000000	shares
CY2017Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	10000000	shares
CY2016Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2017Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0	shares
CY2016Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2017Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2015	us-gaap	Premiums Earned Net PremiumsEarnedNet	52409000000	USD
CY2016	us-gaap	Premiums Earned Net PremiumsEarnedNet	53021000000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	52380000000	USD
CY2015	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	1061000000	USD
CY2016	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2015	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
CY2016	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
CY2017	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	1779000000	USD
CY2015	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1065000000	USD
CY2016	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1426000000	USD
CY2017	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1111000000	USD
CY2015	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	298000000	USD
CY2016	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	-2000000	USD
CY2017	us-gaap	Proceeds From Repayments Of Commercial Paper ProceedsFromRepaymentsOfCommercialPaper	-153000000	USD
CY2015	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	5493000000	USD
CY2016	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	4312000000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2768000000	USD
CY2015	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	1000000	USD
CY2016	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	2000000	USD
CY2015	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	23000000	USD
CY2016	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	14000000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	63000000	USD
CY2016Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	3195000000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	3560000000	USD
CY2016Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1505000000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	1584000000	USD
CY2015	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	61000000	USD
CY2016	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	39000000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	20000000	USD
CY2016Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	1280000000	USD
CY2017Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	854000000	USD
CY2015	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	666000000	USD
CY2016	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	767000000	USD
CY2017	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	844000000	USD
CY2014Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	78000000	USD
CY2015Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	85000000	USD
CY2016Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	76000000	USD
CY2017Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	70000000	USD
CY2016Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	822000000	USD
CY2017Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	824000000	USD
CY2015	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2016	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	0	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	800000000	USD
CY2015	us-gaap	Restricted Stock Expense RestrictedStockExpense	99000000	USD
CY2016	us-gaap	Restricted Stock Expense RestrictedStockExpense	106000000	USD
CY2017	us-gaap	Restricted Stock Expense RestrictedStockExpense	145000000	USD
CY2017	us-gaap	Restructuring And Related Cost Expected Number Of Positions Eliminated RestructuringAndRelatedCostExpectedNumberOfPositionsEliminated	3600	employee
CY2017	us-gaap	Restructuring Charges RestructuringCharges	148000000	USD
CY2016Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	11454000000	USD
CY2017Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	13670000000	USD
CY2015	us-gaap	Revenues Revenues	54289000000	USD
CY2016Q1	us-gaap	Revenues Revenues	13800000000	USD
CY2016Q2	us-gaap	Revenues Revenues	14007000000	USD
CY2016Q3	us-gaap	Revenues Revenues	13694000000	USD
CY2016Q4	us-gaap	Revenues Revenues	12878000000	USD
CY2016	us-gaap	Revenues Revenues	54379000000	USD
CY2017Q1	us-gaap	Revenues Revenues	13762000000	USD
CY2017Q2	us-gaap	Revenues Revenues	13534000000	USD
CY2017Q3	us-gaap	Revenues Revenues	13282000000	USD
CY2017Q4	us-gaap	Revenues Revenues	13189000000	USD
CY2017	us-gaap	Revenues Revenues	53767000000	USD
CY2015	us-gaap	Sales Revenue Net SalesRevenueNet	53815000000	USD
CY2016	us-gaap	Sales Revenue Net SalesRevenueNet	53990000000	USD
CY2017	us-gaap	Sales Revenue Net SalesRevenueNet	53362000000	USD
CY2015	us-gaap	Sales Revenue Services Net SalesRevenueServicesNet	1406000000	USD
CY2016	us-gaap	Sales Revenue Services Net SalesRevenueServicesNet	969000000	USD
CY2017	us-gaap	Sales Revenue Services Net SalesRevenueServicesNet	982000000	USD
CY2015	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	7295000000	USD
CY2016	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	7173000000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	6567000000	USD
CY2015	us-gaap	Share Based Compensation ShareBasedCompensation	109000000	USD
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	115000000	USD
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	137.54
CY2015	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	28000000	USD
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	18000000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	44000000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	25000	shares
CY2017	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	182.46
CY2017	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	64000000	USD
CY2015	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	10000000	USD
CY2016	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	9000000	USD
CY2017	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	12000000	USD
CY2014Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	1000000000	USD
CY2017	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	218.06
CY2017Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	20000000	USD
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P3Y6M
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P5Y
CY2014Q3	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	2000000000	USD
CY2017Q1	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	2250000000.00	USD
CY2017Q4	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	3000000000.0	USD
CY2014Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	816000000	USD
CY2014Q4	us-gaap	Stockholders Equity StockholdersEquity	9646000000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	358000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	57000000	USD
CY2016Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1022000	shares
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	863000	shares
CY2016Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	143.04
CY2017Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	181.44
CY2017	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	128.34
CY2016Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	300000000	USD
CY2017Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	150000000	USD
CY2017Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	4598000000	USD
CY2017Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	1100000000	USD
CY2016Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Balance StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance	7700000000	USD
CY2017Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Balance StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance	8000000000	USD
CY2016Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Required StatutoryAccountingPracticesStatutoryCapitalAndSurplusRequired	4800000000	USD
CY2017Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Required StatutoryAccountingPracticesStatutoryCapitalAndSurplusRequired	4800000000	USD
CY2017	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	492000	shares
CY2015	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	USD
CY2016	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	USD
CY2017	us-gaap	Stock Issued During Period Value Restricted Stock Award Gross StockIssuedDuringPeriodValueRestrictedStockAwardGross	0	USD
CY2015	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	23000000	USD
CY2016	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	13000000	USD
CY2015Q4	us-gaap	Stockholders Equity StockholdersEquity	10346000000	USD
CY2016Q4	us-gaap	Stockholders Equity StockholdersEquity	10685000000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	9842000000	USD
CY2015	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	44397000000	USD
CY2016	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	45318000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	44001000000	USD
CY2015	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-236000000	USD
CY2016	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-582000000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-483000000	USD
CY2017Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	150000000	USD
CY2017Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	38000000	USD
CY2017Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	7000000	USD
CY2015	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	151142000	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	150917000	shares
CY2015	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	385000000	USD
CY2016	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	104000000	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	3365000000	USD
CY2017Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	226000000	USD
CY2017Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	8000000	USD
CY2016Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	49189811	shares
CY2017Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	60893762	shares
CY2016Q4	us-gaap	Treasury Stock Value TreasuryStockValue	3298000000	USD
CY2017Q4	us-gaap	Treasury Stock Value TreasuryStockValue	6325000000	USD
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	145585000	shares
CY2015	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	149455000	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	149375000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	144493000	shares
CY2017	us-gaap	Nature Of Operations NatureOfOperations	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;padding-bottom:12px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">REPORTING ENTITY</font></div><div style="line-height:120%;padding-bottom:12px;text-indent:16px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-style:italic;font-weight:bold;">Nature of Operations</font></div><div style="line-height:120%;padding-bottom:12px;text-align:justify;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Humana Inc., headquartered in Louisville, Kentucky, </font><font style="font-family:inherit;font-size:10pt;">is a leading health and well-being company committed to helping our millions of medical and specialty members achieve their best health. Our successful history in care delivery and health plan administration is helping us create a new kind of integrated care with the power to improve health and well‐being and lower costs. Our efforts are leading to a better quality of life for people with Medicare, families, individuals, military service personnel, and communities at large. To accomplish that, we support physicians and other health care professionals as they work to deliver the right care in the right place for their patients, our members. Our range of clinical capabilities, resources and tools, such as in‐home care, behavioral health, pharmacy services, data analytics and wellness solutions, combine to produce a simplified experience that makes health care easier to navigate and more effective.</font><font style="font-family:inherit;font-size:10pt;"> References throughout these notes to consolidated financial statements to “we,” “us,” “our,” “Company,” and “Humana,” mean Humana Inc. and its subsidiaries. We derived approximately </font><font style="font-family:inherit;font-size:10pt;">79%</font><font style="font-family:inherit;font-size:10pt;"> of our total premiums and services revenue from contracts with the federal government in </font><font style="font-family:inherit;font-size:10pt;">2017</font><font style="font-family:inherit;font-size:10pt;">, including </font><font style="font-family:inherit;font-size:10pt;">15%</font><font style="font-family:inherit;font-size:10pt;"> related to our federal government contracts with the Centers for Medicare and Medicaid Services, or CMS, to provide health insurance coverage for individual Medicare Advantage members in Florida. CMS is the federal government’s agency responsible for administering the Medicare program.</font></div></div>

Files In Submission

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$HUM
HUMANA INC Stock $hum

2016 Q4 Form 10-K Financial Statement

#000004907118000014 Filed on February 16, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$HUM HUMANA INC Stock $hum

2016 Q4 Form 10-K Financial Statement

#000004907118000014 Filed on February 16, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$HUM
HUMANA INC Stock $hum