$elv 2018 Q4 10-Q

Concept	2018 Q4	2018 Q3	2017 Q3
Revenue	$23.37B	$23.25B	$22.43B
YoY Change	3.05%	3.68%	4.78%
Cost Of Revenue		$0.00	$18.10B
YoY Change		-100.0%	6.98%
Gross Profit		$23.25B	$4.322B
YoY Change		437.97%	-3.56%
Gross Profit Margin		100.0%	19.27%
Selling, General & Admin	$3.618B	$3.546B	$3.011B
YoY Change	6.63%	17.77%	-3.64%
% of Gross Profit		15.25%	69.67%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$288.0M	$288.0M	$223.0M
YoY Change	26.87%	29.15%	-2.19%
% of Gross Profit		1.24%	5.16%
Operating Expenses	$22.65B	$3.546B	$3.011B
YoY Change	2.43%	17.77%	-3.64%
Operating Profit		$1.249B	$982.0M
YoY Change		27.19%	-8.91%
Interest Expense	-$189.0M	$188.0M	$150.0M
YoY Change	15.24%	25.33%	-13.24%
% of Operating Profit		15.05%	15.27%
Other Income/Expense, Net
YoY Change
Pretax Income	$542.0M	$1.242B	$1.119B
YoY Change	330.16%	10.99%	-1.54%
Income Tax	$146.0M	$282.0M	$372.0M
% Of Pretax Income	26.94%	22.71%	33.24%
Net Earnings	$424.0M	$960.0M	$747.0M
YoY Change	-65.58%	28.51%	20.91%
Net Earnings / Revenue	1.81%	4.13%	3.33%
Basic Earnings Per Share	$1.64	$3.70	$2.87
Diluted Earnings Per Share	$1.61	$3.62	$2.80
COMMON SHARES
Basic Shares Outstanding	258.6M shares	259.5M shares	260.5M shares
Diluted Shares Outstanding		265.4M shares	267.0M shares

Concept	2018 Q4	2018 Q3	2017 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$20.63B	$21.65B	$24.79B
YoY Change	-1.72%	-12.68%	19.41%
Cash & Equivalents	$3.934B	$4.260B	$6.097B
Short-Term Investments	$16.69B	$17.39B	$18.70B
Other Short-Term Assets	$2.104B	$2.875B	$1.822B
YoY Change	-6.45%	57.79%	-4.45%
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$34.32B	$37.11B	$36.97B
YoY Change	-5.36%	0.36%	12.3%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.735B	$2.592B	$2.049B
YoY Change	25.75%	26.49%	2.12%
Goodwill	$20.50B	$20.47B	$17.59B
YoY Change	6.62%	16.38%	0.15%
Intangibles	$9.007B	$9.101B	$7.841B
YoY Change	7.64%	16.08%	-2.14%
Long-Term Investments	$22.45B	$23.79B	$23.18B
YoY Change	-9.94%	2.63%	3.28%
Other Assets	$758.0M	$1.074B	$850.9M
YoY Change	34.16%	26.22%	-27.18%
Total Long-Term Assets	$37.25B	$37.34B	$31.34B
YoY Change	8.67%	19.15%	-0.44%
TOTAL ASSETS
Total Short-Term Assets	$34.32B	$37.11B	$36.97B
Total Long-Term Assets	$37.25B	$37.34B	$31.34B
Total Assets	$71.57B	$74.45B	$68.31B
YoY Change	1.46%	8.98%	6.07%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$4.959B	$6.286B	$4.454B
YoY Change	-1.29%	41.13%	19.83%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$1.145B	$1.270B	$1.180B
YoY Change	-10.2%	7.63%	168.18%
Long-Term Debt Due	$849.0M	$849.0M	$1.273B
YoY Change	-33.41%	-33.33%	37.23%
Total Short-Term Liabilities	$21.97B	$24.17B	$24.41B
YoY Change	-5.96%	-0.98%	16.05%
LONG-TERM LIABILITIES
Long-Term Debt	$17.22B	$17.30B	$13.78B
YoY Change	-0.95%	25.57%	-3.26%
Other Long-Term Liabilities	$1.182B	$1.145B	$944.0M
YoY Change	27.78%	21.29%	-9.29%
Total Long-Term Liabilities	$18.40B	$18.45B	$14.72B
YoY Change	0.5%	25.29%	-3.68%
TOTAL LIABILITIES
Total Short-Term Liabilities	$21.97B	$24.17B	$24.41B
Total Long-Term Liabilities	$18.40B	$18.45B	$14.72B
Total Liabilities	$43.03B	$45.35B	$42.36B
YoY Change	-2.29%	7.06%	6.82%
SHAREHOLDERS EQUITY
Retained Earnings	$19.99B	$20.18B	$17.31B
YoY Change	10.71%	16.61%	5.76%
Common Stock	$3.000M	$3.000M	$2.600M
YoY Change	0.0%	15.38%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$28.54B	$29.09B	$25.95B
YoY Change
Total Liabilities & Shareholders Equity	$71.57B	$74.45B	$68.31B
YoY Change	1.46%	8.98%	6.07%

Concept	2018 Q4	2018 Q3	2017 Q3
OPERATING ACTIVITIES
Net Income	$424.0M	$960.0M	$747.0M
YoY Change	-65.58%	28.51%	20.91%
Depreciation, Depletion And Amortization	$288.0M	$288.0M	$223.0M
YoY Change	26.87%	29.15%	-2.19%
Cash From Operating Activities	$463.0M	$607.0M	$2.405B
YoY Change	-135.59%	-74.76%	149.48%
INVESTING ACTIVITIES
Capital Expenditures	-$320.0M	-$355.0M	-$218.0M
YoY Change	12.68%	62.84%	32.12%
Acquisitions
YoY Change
Other Investing Activities	$1.093B	-$332.0M	$1.025B
YoY Change	-132.75%	-132.39%	48.98%
Cash From Investing Activities	$773.0M	-$688.0M	$807.0M
YoY Change	-121.35%	-185.25%	54.3%
FINANCING ACTIVITIES
Cash Dividend Paid	$193.0M	$195.0M	$181.0M
YoY Change	7.22%	7.73%	5.79%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-1.561B	-341.0M	-1.676B
YoY Change	-164.16%	-79.65%	219.24%
NET CHANGE
Cash From Operating Activities	463.0M	607.0M	2.405B
Cash From Investing Activities	773.0M	-688.0M	807.0M
Cash From Financing Activities	-1.561B	-341.0M	-1.676B
Net Change In Cash	-325.0M	-422.0M	1.536B
YoY Change	-86.94%	-127.47%	59.67%
FREE CASH FLOW
Cash From Operating Activities	$463.0M	$607.0M	$2.405B
Capital Expenditures	-$320.0M	-$355.0M	-$218.0M
Free Cash Flow	$783.0M	$962.0M	$2.623B
YoY Change	-176.99%	-63.32%	132.33%

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2018Q3	antm	Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-2000000	USD
CY2018Q3	antm	Numberofstatesinwhichcustomersareservedthroughsubsidiaries Numberofstatesinwhichcustomersareservedthroughsubsidiaries	25	states
CY2017Q4	antm	Equitysecurities Longterm EquitysecuritiesLongterm	33000000	USD
CY2018Q3	antm	Equitysecurities Longterm EquitysecuritiesLongterm	34000000	USD
CY2018Q3	antm	Gross Premium Tax Rate GrossPremiumTaxRate	0.0235
CY2017Q4	antm	Increase In Stock Repurchase Program Authorization IncreaseInStockRepurchaseProgramAuthorization	5000000000	USD
CY2017Q4	antm	Liability For Future Policy Benefits Current LiabilityForFuturePolicyBenefitsCurrent	70000000	USD
CY2017Q3	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-3000000	USD
CY2017Q3	antm	Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-3000000	USD
CY2018Q3	antm	Liability For Future Policy Benefits Current LiabilityForFuturePolicyBenefitsCurrent	71000000	USD
	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-8000000	USD
CY2018Q3	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-2000000	USD
CY2017Q3	antm	Available For Sale Securities Accumulated Other Comprehensive Income Net Deferred Tax Liability AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability	-310000000	USD
CY2018Q3	antm	Liability For Unpaid Claims And Claims Adjustment Expense Purchase Adjustments LiabilityForUnpaidClaimsAndClaimsAdjustmentExpensePurchaseAdjustments	199000000	USD
CY2018Q3	antm	Merger Agreement Termination Fee MergerAgreementTerminationFee	1850000000	USD
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CY2017Q3	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	115000000	USD
	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	138000000	USD
CY2018Q3	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	27000000	USD
	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	5000000	USD
	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-7000000	USD
	antm	Payments For Proceeds From Financing Derivatives PaymentsForProceedsFromFinancingDerivatives	176000000	USD
CY2018Q3	antm	Number Of Counties In State Of Kansas Company Does Not Serve NumberOfCountiesInStateOfKansasCompanyDoesNotServe	30	county
CY2018Q3	antm	Number Of Medical Members NumberOfMedicalMembers	39500000	medical_member
	antm	Payments For Proceeds From Financing Derivatives PaymentsForProceedsFromFinancingDerivatives	-22000000	USD
	antm	Paymentstoacquireequitysecurities Paymentstoacquireequitysecurities	481000000	USD
	antm	Paymentstoacquireequitysecurities Paymentstoacquireequitysecurities	812000000	USD
CY2018Q3	antm	Available For Sale Securities Accumulated Other Comprehensive Income Net Deferred Tax Liability AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability	24000000	USD
CY2017Q4	antm	Available For Sale Securities Debt Maturities Amortized Cost Noncurrent AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent	555000000	USD
CY2018Q3	antm	Available For Sale Securities Debt Maturities Amortized Cost Noncurrent AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent	501000000	USD
CY2017Q3	antm	Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset	0	USD
CY2018Q3	antm	Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset	0	USD
CY2017Q3	antm	Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	127000000	USD
CY2018Q3	antm	Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	66000000	USD
CY2017Q3	antm	Deferred Net Actuarial Gain Loss Postretirement Benefits DeferredNetActuarialGainLossPostretirementBenefits	-138000000	USD
CY2018Q3	antm	Deferred Net Actuarial Gain Loss Postretirement Benefits DeferredNetActuarialGainLossPostretirementBenefits	-75000000	USD
CY2017Q3	antm	Deferred Prior Service Cost Credit Postretirement Benefit Plans DeferredPriorServiceCostCreditPostretirementBenefitPlans	49000000	USD
CY2018Q3	antm	Deferred Prior Service Cost Credit Postretirement Benefit Plans DeferredPriorServiceCostCreditPostretirementBenefitPlans	37000000	USD
CY2017Q3	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Adjustments Net Of Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeAdjustmentsNetOfTax	-385000000	USD
CY2018Q3	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Adjustments Net Of Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeAdjustmentsNetOfTax	-435000000	USD
CY2017Q3	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Net Deferred Tax Asset DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	-249000000	USD
CY2018Q3	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Net Deferred Tax Asset DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	-153000000	USD
CY2017Q4	antm	Equity Securities EquitySecurities	3632000000	USD
CY2018Q3	antm	Equity Securities EquitySecurities	2306000000	USD
CY2017Q4	antm	Equity Securities Current EquitySecuritiesCurrent	3599000000	USD
CY2018Q3	antm	Equity Securities Current EquitySecuritiesCurrent	2272000000	USD
	antm	Potentially Dilutive Restricted Stock Units Contingent On Operating Results PotentiallyDilutiveRestrictedStockUnitsContingentOnOperatingResults	400000	shares
	antm	Potentially Dilutive Restricted Stock Units Contingent On Operating Results PotentiallyDilutiveRestrictedStockUnitsContingentOnOperatingResults	300000	shares
	antm	Proceedsfromsaleofequitysecurities Proceedsfromsaleofequitysecurities	621000000	USD
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	antm	Reclassificationofstrandedtaxeffectsresultingfromthe Tax Cutsand Jobs Act ReclassificationofstrandedtaxeffectsresultingfromtheTaxCutsandJobsAct	91000000	USD
CY2017	antm	Securities Lending Transactions Initial Collateral Percentage Value SecuritiesLendingTransactionsInitialCollateralPercentageValue	1.02
	antm	Securities Lending Transactions Initial Collateral Percentage Value SecuritiesLendingTransactionsInitialCollateralPercentageValue	1.02
CY2017	antm	Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan	1.04
	antm	Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan	1.03
CY2017Q4	antm	Self Funded Receivables Net SelfFundedReceivablesNet	2580000000	USD
CY2018Q3	antm	Self Funded Receivables Net SelfFundedReceivablesNet	2631000000	USD
CY2017Q4	antm	Selffunded Receivables Allowance For Doubtful Accounts SelffundedReceivablesAllowanceForDoubtfulAccounts	153000000	USD
CY2018Q3	antm	Selffunded Receivables Allowance For Doubtful Accounts SelffundedReceivablesAllowanceForDoubtfulAccounts	40000000	USD
	antm	Stock Repurchased And Retired During Period Average Price StockRepurchasedAndRetiredDuringPeriodAveragePrice	186.80
	antm	Stock Repurchased And Retired During Period Average Price StockRepurchasedAndRetiredDuringPeriodAveragePrice	240.15
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2018
	dei	Document Period End Date DocumentPeriodEndDate	2018-09-30
	dei	Document Type DocumentType	10-Q
	dei	Entity Central Index Key EntityCentralIndexKey	0001156039
CY2018Q3	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	258931814	shares
CY2018Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	258642095	shares
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Registrant Name EntityRegistrantName	Anthem, Inc.
	dei	Trading Symbol TradingSymbol	ANTM
CY2017Q4	invest	Derivative Notional Amount DerivativeNotionalAmount	2048000000	USD
CY2018Q3	invest	Derivative Notional Amount DerivativeNotionalAmount	1653000000	USD
CY2017Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	5024000000	USD
CY2018Q3	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	6286000000	USD
CY2017Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	163000000	USD
CY2018Q3	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	163000000	USD
CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	551000000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-95000000	USD
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CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	54000000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	28000000	USD
CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-2000000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-2000000	USD
CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-126000000	USD
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-101000000	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-811000000	USD
CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	0	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	2000000	USD
CY2017Q3	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities	0	USD
CY2018Q3	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities	2000000	USD
CY2017Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	8547000000	USD
CY2018Q3	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	9720000000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	581000000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	752000000	USD
	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt Subsequent Adjustments AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebtSubsequentAdjustments	-1000000	USD
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CY2017Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	42000000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	124000000	USD
CY2018Q3	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	91000000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	265000000	USD
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	500000	shares
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CY2017Q4	us-gaap	Assets Assets	70540000000	USD
CY2018Q3	us-gaap	Assets Assets	74445000000	USD
CY2017Q4	us-gaap	Assets Current AssetsCurrent	36263000000	USD
CY2018Q3	us-gaap	Assets Current AssetsCurrent	37108000000	USD
CY2017Q4	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	24001000000	USD
CY2018Q3	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	22792000000	USD
CY2017Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	17055000000	USD
CY2018Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	17504000000	USD
CY2017Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	941000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	170000000	USD
CY2017Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainLossBeforeTax	861000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainLossBeforeTax	-119000000	USD
CY2017Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	80000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	289000000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	17377000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	17390000000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	561000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	496000000	USD
CY2017Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	47000000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	134000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	12000000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	73000000	USD
CY2017Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	9000000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	49000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	16000000	USD
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CY2017Q3	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	-49000000	USD
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CY2018Q3	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	12000000	USD
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CY2017Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	21307000000	USD
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CY2018Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	22009000000	USD
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CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	4075000000	USD
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CY2017Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	1956000000	USD
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CY2017Q4	us-gaap	Ceded Premiums Payable CededPremiumsPayable	105000000	USD
CY2018Q3	us-gaap	Ceded Premiums Payable CededPremiumsPayable	38000000	USD
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CY2017Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.65
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CY2017Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.70
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CY2018Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.75
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CY2017Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	256084913	shares
CY2018Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	258931814	shares
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CY2017Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	756000000	USD
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CY2018Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	931000000	USD
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CY2018Q1	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	320000000	USD
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CY2017Q3	us-gaap	Deferred Tax Assets Unrealized Currency Losses DeferredTaxAssetsUnrealizedCurrencyLosses	1000000	USD
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CY2017Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	1727000000	USD
CY2018Q3	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2063000000	USD
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CY2017Q3	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax	1000000	USD
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CY2017Q4	us-gaap	Deposits Received For Securities Loaned At Carrying Value DepositsReceivedForSecuritiesLoanedAtCarryingValue	454000000	USD
CY2018Q3	us-gaap	Deposits Received For Securities Loaned At Carrying Value DepositsReceivedForSecuritiesLoanedAtCarryingValue	741000000	USD
	us-gaap	Depreciation Depreciation	82000000	USD
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CY2017Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	1000000	USD
CY2018Q3	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	10000000	USD
CY2017Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	3000000	USD
CY2018Q3	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	10000000	USD
CY2017Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	2000000	USD
CY2018Q3	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	0	USD
CY2017Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	21000000	USD
CY2018Q3	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	21000000	USD
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CY2018Q3	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	11000000	USD
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CY2017Q4	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	12000000	USD
CY2018Q3	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	14000000	USD
CY2017Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	1000000	USD
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CY2017Q2	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2017-06-23
CY2017Q3	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2017-09-25
CY2018Q1	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2018-03-23
CY2018Q2	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2018-06-25
CY2018Q3	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2018-09-25
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CY2017Q1	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2017-02-22
CY2017Q2	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2017-04-27
CY2017Q3	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2017-07-25
CY2018Q1	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2018-01-30
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CY2018Q3	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2018-07-24
CY2017Q1	us-gaap	Dividends Payable Date Of Record Day Month And Year DividendsPayableDateOfRecordDayMonthAndYear	2017-03-10
CY2017Q2	us-gaap	Dividends Payable Date Of Record Day Month And Year DividendsPayableDateOfRecordDayMonthAndYear	2017-06-09
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	7000000	USD
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CY2018Q1	us-gaap	Dividends Payable Date Of Record Day Month And Year DividendsPayableDateOfRecordDayMonthAndYear	2018-03-09
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CY2017Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	48000000	USD
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CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	40000000	USD
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CY2017Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	3000000	USD
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CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	5000000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	21000000	USD
CY2017Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	19000000	USD
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CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	30000000	USD
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CY2017Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	28000000	USD
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CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	15000000	USD
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CY2016Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	481000000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	520000000	USD
CY2017Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	527000000	USD
CY2017Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	537000000	USD
CY2018Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	646000000	USD
CY2018Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	646000000	USD
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CY2018Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	3216000000	USD
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CY2017Q4	us-gaap	Goodwill Goodwill	19231000000	USD
CY2018Q3	us-gaap	Goodwill Goodwill	20468000000	USD
CY2017Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1119000000	USD
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CY2017Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	372000000	USD
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CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	282000000	USD
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CY2018Q3	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	76000000	USD
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	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	160000000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	251000000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	190000000	USD
	us-gaap	Increase Decrease In Outstanding Checks Financing Activities IncreaseDecreaseInOutstandingChecksFinancingActivities	-127000000	USD
	us-gaap	Increase Decrease In Outstanding Checks Financing Activities IncreaseDecreaseInOutstandingChecksFinancingActivities	97000000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-612000000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	823000000	USD
	us-gaap	Increase Decrease In Securities Lending Payable IncreaseDecreaseInSecuritiesLendingPayable	-173000000	USD
	us-gaap	Increase Decrease In Securities Lending Payable IncreaseDecreaseInSecuritiesLendingPayable	287000000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	26000000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	17000000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	970000000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-42000000	USD
CY2017Q3	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	22097000000	USD
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	66614000000	USD
CY2018Q3	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	22980000000	USD
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	68037000000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	8368000000	USD
CY2018Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	9101000000	USD
CY2017Q3	us-gaap	Interest Expense InterestExpense	150000000	USD
	us-gaap	Interest Expense InterestExpense	575000000	USD
CY2018Q3	us-gaap	Interest Expense InterestExpense	188000000	USD
	us-gaap	Interest Expense InterestExpense	564000000	USD
CY2017Q4	us-gaap	Liabilities Liabilities	44037000000	USD
CY2018Q3	us-gaap	Liabilities Liabilities	45351000000	USD
CY2017Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	70540000000	USD
CY2018Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	74445000000	USD
CY2017Q4	us-gaap	Liabilities Current LiabilitiesCurrent	23356000000	USD
CY2018Q3	us-gaap	Liabilities Current LiabilitiesCurrent	24174000000	USD
CY2017Q4	us-gaap	Liabilities Fair Value Disclosure Recurring LiabilitiesFairValueDisclosureRecurring	21000000	USD
CY2018Q3	us-gaap	Liabilities Fair Value Disclosure Recurring LiabilitiesFairValueDisclosureRecurring	21000000	USD
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7893000000	USD
CY2017Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7964000000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7992000000	USD
CY2018Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7658000000	USD
CY2017Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	647000000	USD
CY2018Q3	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	669000000	USD
CY2017Q4	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	11012000000	USD
CY2018Q3	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	10658000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	45998000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	45514000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	5932000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	6662000000	USD
CY2017Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	17704000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	52439000000	USD
CY2018Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	17781000000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	51710000000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7354000000	USD
CY2017Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7863000000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7887000000	USD
CY2018Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7620000000	USD
CY2017Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	1275000000	USD
CY2018Q3	us-gaap	Long Term Debt Current LongTermDebtCurrent	849000000	USD
CY2017Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	17382000000	USD
CY2018Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	17300000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2006000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-680000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1462000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2032000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	5486000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3364000000	USD
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	747000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	2612000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	960000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	3325000000	USD
CY2017Q3	us-gaap	Net Investment Income NetInvestmentIncome	220000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	628000000	USD
CY2018Q3	us-gaap	Net Investment Income NetInvestmentIncome	250000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	708000000	USD
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2018Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	50	states
CY2017Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	982000000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	3794000000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	1249000000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	4676000000	USD
CY2017Q4	us-gaap	Other Assets Current OtherAssetsCurrent	2249000000	USD
CY2018Q3	us-gaap	Other Assets Current OtherAssetsCurrent	2875000000	USD
CY2017Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	565000000	USD
CY2018Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1074000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	88000000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	297000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-45000000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-378000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	3000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	0	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-1000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-1000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	9000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	142000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-29000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-299000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	9000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	142000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-29000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-299000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-5000000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-13000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-7000000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-22000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	79000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	107000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-9000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-25000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	43000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	58000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-3000000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-7000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-7000000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-79000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	4000000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	83000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-5000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-68000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	2000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	34000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	2000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	36000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-1000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-9000000	USD
CY2017Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	9000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	190000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-36000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-353000000	USD
CY2017Q3	us-gaap	Other Income OtherIncome	1300000000	USD
	us-gaap	Other Income OtherIncome	4053000000	USD
CY2018Q3	us-gaap	Other Income OtherIncome	1529000000	USD
	us-gaap	Other Income OtherIncome	4435000000	USD
CY2017Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	3343000000	USD
CY2018Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	3306000000	USD
CY2017Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	925000000	USD
CY2018Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1145000000	USD
CY2017Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	3344000000	USD
CY2018Q3	us-gaap	Other Long Term Investments OtherLongTermInvestments	3572000000	USD
CY2017Q4	us-gaap	Other Policyholder Funds OtherPolicyholderFunds	2950000000	USD
CY2018Q3	us-gaap	Other Policyholder Funds OtherPolicyholderFunds	2929000000	USD
CY2017Q4	us-gaap	Other Receivables OtherReceivables	2267000000	USD
CY2018Q3	us-gaap	Other Receivables OtherReceivables	2374000000	USD
CY2017Q4	us-gaap	Other Short Term Investments OtherShortTermInvestments	17000000	USD
CY2018Q3	us-gaap	Other Short Term Investments OtherShortTermInvestments	21000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	0	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	-4000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	2000000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	2000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	6000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	23000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	8000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	20000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	0	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-2000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-2000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-2000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	0	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	-4000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	2000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	2000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	0	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-3000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-2000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-2000000	USD
CY2017Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	6000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	21000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	6000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	18000000	USD
CY2017Q4	us-gaap	Payables To Broker Dealers And Clearing Organizations PayablesToBrokerDealersAndClearingOrganizations	113000000	USD
CY2018Q3	us-gaap	Payables To Broker Dealers And Clearing Organizations PayablesToBrokerDealersAndClearingOrganizations	168000000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	51930000000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	52176000000	USD
	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-65000000	USD
	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-12000000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-17000000	USD

antm

Percentageofrevenuessubjecttonewrevenueguidanceunder Asc606

PercentageofrevenuessubjecttonewrevenueguidanceunderASC606

0.06

CY2018Q3

antm

Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax

AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax

-2000000

USD

CY2018Q3

antm

Numberofstatesinwhichcustomersareservedthroughsubsidiaries

25

states

CY2017Q4

antm

Equitysecurities Longterm

EquitysecuritiesLongterm

33000000

USD

CY2018Q3

antm

Equitysecurities Longterm

EquitysecuritiesLongterm

34000000

USD

CY2018Q3

antm

Gross Premium Tax Rate

GrossPremiumTaxRate

0.0235

CY2017Q4

antm

Increase In Stock Repurchase Program Authorization

IncreaseInStockRepurchaseProgramAuthorization

5000000000

USD

CY2017Q4

antm

Liability For Future Policy Benefits Current

LiabilityForFuturePolicyBenefitsCurrent

70000000

USD

CY2017Q3

antm

Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense

OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense

-3000000

USD

CY2017Q3

antm

Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax

AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax

-3000000

USD

CY2018Q3

antm

Liability For Future Policy Benefits Current

LiabilityForFuturePolicyBenefitsCurrent

71000000

USD

antm

Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense

OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense

-8000000

USD

CY2018Q3

antm

Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense

OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense

-2000000

USD

CY2017Q3

antm

Available For Sale Securities Accumulated Other Comprehensive Income Net Deferred Tax Liability

AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability

-310000000

USD

CY2018Q3

antm

Liability For Unpaid Claims And Claims Adjustment Expense Purchase Adjustments

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpensePurchaseAdjustments

199000000

USD

CY2018Q3

antm

Merger Agreement Termination Fee

MergerAgreementTerminationFee

1850000000

USD

antm

Net Adjustment To Additional Paid In Capital For Equity Hedge

NetAdjustmentToAdditionalPaidInCapitalForEquityHedge

1000000

USD

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CY2017Q4

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CY2018Q3

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CY2017Q3

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Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset

CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset

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CY2018Q3

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Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset

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CY2017Q3

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Deferred Net Actuarial Gain Loss Postretirement Benefits

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CY2018Q3

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Deferred Net Actuarial Gain Loss Postretirement Benefits

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CY2017Q3

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Deferred Prior Service Cost Credit Postretirement Benefit Plans

DeferredPriorServiceCostCreditPostretirementBenefitPlans

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CY2018Q3

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Deferred Prior Service Cost Credit Postretirement Benefit Plans

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CY2017Q3

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Defined Benefit Plan Accumulated Other Comprehensive Income Adjustments Net Of Tax

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CY2018Q3

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Potentially Dilutive Restricted Stock Units Contingent On Operating Results

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Securities Lending Transactions Initial Collateral Percentage Value

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CY2017

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Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan

SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan

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Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan

SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan

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SelffundedReceivablesAllowanceForDoubtfulAccounts

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CY2018Q3

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Selffunded Receivables Allowance For Doubtful Accounts

SelffundedReceivablesAllowanceForDoubtfulAccounts

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StockRepurchasedAndRetiredDuringPeriodAveragePrice

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Stock Repurchased And Retired During Period Average Price

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Current Fiscal Year End Date

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Document Fiscal Period Focus

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Document Fiscal Year Focus

DocumentFiscalYearFocus

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Document Period End Date

DocumentPeriodEndDate

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Document Type

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Entity Central Index Key

EntityCentralIndexKey

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CY2018Q3

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EntityCommonStockSharesOutstanding

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CY2018Q4

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Entity Common Stock Shares Outstanding

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Entity Filer Category

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Entity Registrant Name

EntityRegistrantName

Anthem, Inc.

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CY2018Q3

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CY2017Q4

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CY2018Q3

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CY2017Q3

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CY2018Q3

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CY2017Q3

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0

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Adjustment For Amortization

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Amortization Of Intangible Assets

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Amortization Of Intangible Assets

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Available For Sale Securities Gross Realized Gains

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us-gaap

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Benefits Losses And Expenses

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Benefits Losses And Expenses

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Benefits Losses And Expenses

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Benefits Losses And Expenses

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Cash And Cash Equivalents At Carrying Value

CashAndCashEquivalentsAtCarryingValue

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Cash And Cash Equivalents Fair Value Disclosure

CashAndCashEquivalentsFairValueDisclosure

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Cash And Cash Equivalents Fair Value Disclosure

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Cash And Cash Equivalents Period Increase Decrease

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Cash And Cash Equivalents Period Increase Decrease

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Ceded Premiums Payable

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Ceded Premiums Payable

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Ceded Premiums Payable

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Commitments And Contingencies

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