$elv 2017 Q2 10-Q

Concept	2017 Q2	2016 Q2
Revenue	$22.41B	$21.46B
YoY Change	4.43%	7.2%
Cost Of Revenue	$17.92B	$16.81B
YoY Change	6.62%	10.52%
Gross Profit	$4.490B	$4.651B
YoY Change	-3.47%	-3.31%
Gross Profit Margin	20.04%	21.68%
Selling, General & Admin	$3.054B	$2.969B
YoY Change	2.85%	-2.36%
% of Gross Profit	68.02%	63.84%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$219.0M	$226.0M
YoY Change	-3.1%	-54.07%
% of Gross Profit	4.88%	4.86%
Operating Expenses	$3.054B	$2.969B
YoY Change	2.85%	-2.36%
Operating Profit	$1.227B	$1.500B
YoY Change	-18.21%	-0.79%
Interest Expense	$189.9M	$185.7M
YoY Change	2.26%	20.51%
% of Operating Profit	15.48%	12.38%
Other Income/Expense, Net
YoY Change
Pretax Income	$1.205B	$1.448B
YoY Change	-16.8%	-7.04%
Income Tax	$350.4M	$667.7M
% Of Pretax Income	29.08%	46.1%
Net Earnings	$855.0M	$780.6M
YoY Change	9.53%	-9.14%
Net Earnings / Revenue	3.82%	3.64%
Basic Earnings Per Share	$3.23	$2.97
Diluted Earnings Per Share	$3.16	$2.91
COMMON SHARES
Basic Shares Outstanding	264.6M shares	263.0M shares
Diluted Shares Outstanding	270.8M shares	268.2M shares

Concept	2017 Q2	2016 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$23.51B	$20.15B
YoY Change	16.7%	1.8%
Cash & Equivalents	$4.561B	$1.583B
Short-Term Investments	$18.95B	$18.56B
Other Short-Term Assets	$1.775B	$2.083B
YoY Change	-14.82%	-4.38%
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$37.13B	$32.96B
YoY Change	12.66%	-0.74%
LONG-TERM ASSETS
Property, Plant & Equipment	$1.976B	$1.990B
YoY Change	-0.71%	3.02%
Goodwill	$17.56B	$17.56B
YoY Change	-0.01%	0.12%
Intangibles	$7.882B	$8.060B
YoY Change	-2.2%	-2.61%
Long-Term Investments	$23.70B	$22.85B
YoY Change	3.73%	1.93%
Other Assets	$778.4M	$862.2M
YoY Change	-9.72%	-0.24%
Total Long-Term Assets	$31.11B	$31.10B
YoY Change	0.01%	0.14%
TOTAL ASSETS
Total Short-Term Assets	$37.13B	$32.96B
Total Long-Term Assets	$31.11B	$31.10B
Total Assets	$68.24B	$64.06B
YoY Change	6.52%	-0.31%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$3.816B	$4.272B
YoY Change	-10.67%	-3.65%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$580.0M	$440.0M
YoY Change	31.82%	-18.52%
Long-Term Debt Due	$624.4M	$927.9M
YoY Change	-32.71%	48.49%
Total Short-Term Liabilities	$22.57B	$20.82B
YoY Change	8.41%	0.69%
LONG-TERM LIABILITIES
Long-Term Debt	$15.09B	$14.20B
YoY Change	6.24%	-8.18%
Other Long-Term Liabilities	$898.3M	$1.480B
YoY Change	-39.3%	20.72%
Total Long-Term Liabilities	$15.99B	$15.68B
YoY Change	1.94%	-6.06%
TOTAL LIABILITIES
Total Short-Term Liabilities	$22.57B	$20.82B
Total Long-Term Liabilities	$15.99B	$15.68B
Total Liabilities	$41.81B	$39.83B
YoY Change	4.96%	-3.33%
SHAREHOLDERS EQUITY
Retained Earnings	$17.67B	$15.92B
YoY Change	10.98%	10.91%
Common Stock	$2.600M	$2.600M
YoY Change	0.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$26.43B	$24.23B
YoY Change
Total Liabilities & Shareholders Equity	$68.24B	$64.06B
YoY Change	6.52%	-0.31%

Concept	2017 Q2	2016 Q2
OPERATING ACTIVITIES
Net Income	$855.0M	$780.6M
YoY Change	9.53%	-9.14%
Depreciation, Depletion And Amortization	$219.0M	$226.0M
YoY Change	-3.1%	-54.07%
Cash From Operating Activities	$393.0M	$669.0M
YoY Change	-41.26%	-42.97%
INVESTING ACTIVITIES
Capital Expenditures	-$170.0M	-$133.0M
YoY Change	27.82%	-5.67%
Acquisitions
YoY Change
Other Investing Activities	-$872.0M	-$183.0M
YoY Change	376.5%	-122.15%
Cash From Investing Activities	-$1.042B	-$317.0M
YoY Change	228.71%	-146.28%
FINANCING ACTIVITIES
Cash Dividend Paid	$172.0M	$170.9M
YoY Change	0.64%	4.27%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-1.564B	-444.0M
YoY Change	252.25%	-73.93%
NET CHANGE
Cash From Operating Activities	393.0M	669.0M
Cash From Investing Activities	-1.042B	-317.0M
Cash From Financing Activities	-1.564B	-444.0M
Net Change In Cash	-2.213B	-92.00M
YoY Change	2305.43%	-159.35%
FREE CASH FLOW
Cash From Operating Activities	$393.0M	$669.0M
Capital Expenditures	-$170.0M	-$133.0M
Free Cash Flow	$563.0M	$802.0M
YoY Change	-29.8%	-38.96%

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2016Q2	antm	Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-8700000	USD
CY2017Q2	antm	Accumulated Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Before Tax AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-3100000	USD
CY2016Q2	antm	Available For Sale Securities Accumulated Other Comprehensive Income Net Deferred Tax Liability AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability	-358600000	USD
CY2017Q2	antm	Available For Sale Securities Accumulated Other Comprehensive Income Net Deferred Tax Liability AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability	-304000000	USD
CY2016Q4	antm	Available For Sale Securities Debt Maturities Amortized Cost Noncurrent AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent	524600000	USD
CY2017Q2	antm	Available For Sale Securities Debt Maturities Amortized Cost Noncurrent AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent	516700000	USD
CY2016Q4	antm	Available For Sale Securities Equity Securities Cost Current AvailableForSaleSecuritiesEquitySecuritiesCostCurrent	1076100000	USD
CY2017Q2	antm	Available For Sale Securities Equity Securities Cost Current AvailableForSaleSecuritiesEquitySecuritiesCostCurrent	1378300000	USD
CY2016Q4	antm	Available For Sale Securities Equity Securities Cost Noncurrent AvailableForSaleSecuritiesEquitySecuritiesCostNoncurrent	27200000	USD
CY2017Q2	antm	Available For Sale Securities Equity Securities Cost Noncurrent AvailableForSaleSecuritiesEquitySecuritiesCostNoncurrent	27300000	USD
CY2017Q2	antm	Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset	100000	USD
CY2016Q2	antm	Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	289000000	USD
CY2016Q2	antm	Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset	9300000	USD
CY2017Q2	antm	Cash Flow Hedging Instruments Accumulated Other Comprehensive Income Net Deferred Tax Asset CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	124600000	USD
CY2016Q2	antm	Deferred Net Actuarial Gain Loss Postretirement Benefits DeferredNetActuarialGainLossPostretirementBenefits	-156500000	USD
CY2017Q2	antm	Deferred Net Actuarial Gain Loss Postretirement Benefits DeferredNetActuarialGainLossPostretirementBenefits	-140900000	USD
CY2016Q2	antm	Deferred Prior Service Cost Credit Postretirement Benefit Plans DeferredPriorServiceCostCreditPostretirementBenefitPlans	66600000	USD
CY2017Q2	antm	Deferred Prior Service Cost Credit Postretirement Benefit Plans DeferredPriorServiceCostCreditPostretirementBenefitPlans	52900000	USD
CY2016Q2	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Adjustments Net Of Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeAdjustmentsNetOfTax	-376500000	USD
CY2017Q2	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Adjustments Net Of Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeAdjustmentsNetOfTax	-390300000	USD
CY2016Q2	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Net Deferred Tax Asset DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	-245100000	USD
CY2017Q2	antm	Defined Benefit Plan Accumulated Other Comprehensive Income Net Deferred Tax Asset DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset	-251600000	USD
CY2017Q2	antm	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Per Share Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPerShareAmount	0.02
	antm	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Per Share Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPerShareAmount	0.09
CY2017Q2	antm	Gross Premium Tax Rate GrossPremiumTaxRate	0.0235
CY2014Q4	antm	Increase In Stock Repurchase Program Authorization IncreaseInStockRepurchaseProgramAuthorization	5000000000	USD
CY2016Q4	antm	Liability For Future Policy Benefits Current LiabilityForFuturePolicyBenefitsCurrent	71800000	USD
CY2017Q2	antm	Liability For Future Policy Benefits Current LiabilityForFuturePolicyBenefitsCurrent	69600000	USD
CY2017Q2	antm	Merger Agreement Termination Fee MergerAgreementTerminationFee	1850000000	USD
CY2016Q2	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	12500000	USD
	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	-112600000	USD
CY2017Q2	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	16200000	USD
	antm	Netrealizedgainslossesonfinancialinstruments Netrealizedgainslossesonfinancialinstruments	23500000	USD
CY2017Q2	antm	Number Of Counties In Geographical Region Served As Independent Licensee NumberOfCountiesInGeographicalRegionServedAsIndependentLicensee	10	county
CY2017Q2	antm	Number Of Counties In State Of Kansas Company Does Not Serve NumberOfCountiesInStateOfKansasCompanyDoesNotServe	30	county
CY2017Q2	antm	Number Of Medical Members NumberOfMedicalMembers	40400000	medical_member
CY2016Q2	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-2600000	USD
	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-5000000	USD
CY2017Q2	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-2900000	USD
	antm	Other Net Change In Unrecognized Periodic Benefit Costs For Defined Benefit Pension And Postretirement Benefit Plans Tax Benefit Expense OtherNetChangeInUnrecognizedPeriodicBenefitCostsForDefinedBenefitPensionAndPostretirementBenefitPlansTaxBenefitExpense	-5200000	USD
	antm	Payments For Proceeds From Financing Derivatives PaymentsForProceedsFromFinancingDerivatives	467500000	USD
	antm	Payments For Proceeds From Financing Derivatives PaymentsForProceedsFromFinancingDerivatives	128400000	USD
	antm	Percentageofrevenuessubjecttonewrevenueguidanceunder Asc606 PercentageofrevenuessubjecttonewrevenueguidanceunderASC606	0.060
	antm	Potentially Dilutive Restricted Stock Units Contingent On Operating Results PotentiallyDilutiveRestrictedStockUnitsContingentOnOperatingResults	500000	shares
	antm	Potentially Dilutive Restricted Stock Units Contingent On Operating Results PotentiallyDilutiveRestrictedStockUnitsContingentOnOperatingResults	100000	shares
	antm	Present Value Of Contract Liability Debt Issuance Costs Related To Equity Units PresentValueOfContractLiabilityDebtIssuanceCostsRelatedToEquityUnits	300000	USD
CY2016	antm	Securities Lending Transactions Initial Collateral Percentage Value SecuritiesLendingTransactionsInitialCollateralPercentageValue	1.02
	antm	Securities Lending Transactions Initial Collateral Percentage Value SecuritiesLendingTransactionsInitialCollateralPercentageValue	1.02
CY2016	antm	Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan	1.03
	antm	Securities Lending Transactions Ratioof Fair Valueof Collateral Held To Securities On Loan SecuritiesLendingTransactionsRatioofFairValueofCollateralHeldToSecuritiesOnLoan	1.03
	antm	Stock Repurchased And Retired During Period Average Price StockRepurchasedAndRetiredDuringPeriodAveragePrice	180.37
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2017
	dei	Document Period End Date DocumentPeriodEndDate	2017-06-30
	dei	Document Type DocumentType	10-Q
	dei	Entity Central Index Key EntityCentralIndexKey	0001156039
CY2017Q2	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	263095951	shares
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Registrant Name EntityRegistrantName	Anthem, Inc.
	dei	Trading Symbol TradingSymbol	ANTM
CY2016Q4	invest	Derivative Notional Amount DerivativeNotionalAmount	16834900000	USD
CY2017Q3	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	262584689	shares
CY2017Q2	invest	Derivative Notional Amount DerivativeNotionalAmount	17501300000	USD
CY2016Q4	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	4014900000	USD
CY2017Q2	us-gaap	Accounts Payable And Accrued Liabilities Current AccountsPayableAndAccruedLiabilitiesCurrent	3815700000	USD
CY2016Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	0	USD
CY2017Q2	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	113000000	USD
CY2016Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	164500000	USD
CY2017Q2	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	158200000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	625400000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	542300000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	-536600000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax AccumulatedOtherComprehensiveIncomeLossCumulativeChangesInNetGainLossFromCashFlowHedgesEffectNetOfTax	-231200000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	54500000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Defined Benefit Pension And Other Postretirement Plans Net Of Tax AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax	53600000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-5600000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-2000000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-364900000	USD
CY2016Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-267900000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-134900000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	26400000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities	200000	USD
CY2016Q2	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities	17100000	USD
CY2017Q2	us-gaap	Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Debt Securities AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxDebtSecurities	100000	USD
CY2016Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	8805100000	USD
CY2017Q2	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	8897000000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	399400000	USD
	us-gaap	Adjustment For Amortization AdjustmentForAmortization	385000000	USD
	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt Subsequent Adjustments AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebtSubsequentAdjustments	-1100000	USD
CY2016Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	47900000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	98300000	USD
CY2017Q2	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	40600000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	82400000	USD
CY2016Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2600000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2200000	shares
CY2017Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1000000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	700000	shares
CY2016Q4	us-gaap	Assets Assets	65083100000	USD
CY2017Q2	us-gaap	Assets Assets	68237600000	USD
CY2016Q4	us-gaap	Assets Current AssetsCurrent	34314900000	USD
CY2017Q2	us-gaap	Assets Current AssetsCurrent	37130700000	USD
CY2016Q4	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	22587700000	USD
CY2017Q2	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	25499600000	USD
CY2016Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	1099000000	USD
CY2017Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	941600000	USD
CY2016Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	115000000	USD
CY2017Q2	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	95300000	USD
CY2016Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	16991800000	USD
CY2017Q2	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	18560500000	USD
CY2016Q4	us-gaap	Available For Sale Securities AvailableForSaleSecurities	19187400000	USD
CY2017Q2	us-gaap	Available For Sale Securities AvailableForSaleSecurities	21329100000	USD
CY2016Q4	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	748600000	USD
CY2017Q2	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	941600000	USD
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CY2017Q2	us-gaap	Available For Sale Securities Accumulated Gross Unrealized Gain Loss Before Tax AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainLossBeforeTax	846300000	USD
CY2016Q4	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	18619700000	USD
CY2017Q2	us-gaap	Available For Sale Securities Amortized Cost AvailableForSaleSecuritiesAmortizedCost	20482800000	USD
CY2016Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	42400000	USD
CY2017Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	22900000	USD
CY2016Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	138500000	USD
CY2017Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	72400000	USD
CY2016Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	6220300000	USD
CY2017Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	4680000000	USD
CY2016Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	816000000	USD
CY2017Q2	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	484800000	USD
CY2016Q4	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	17163100000	USD
CY2017Q2	us-gaap	Available For Sale Securities Debt Securities Current AvailableForSaleSecuritiesDebtSecuritiesCurrent	18948200000	USD
CY2016Q4	us-gaap	Available For Sale Securities Debt Securities Noncurrent AvailableForSaleSecuritiesDebtSecuritiesNoncurrent	524400000	USD
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CY2016Q4	us-gaap	Available For Sale Securities Equity Securities Current AvailableForSaleSecuritiesEquitySecuritiesCurrent	1468500000	USD
CY2017Q2	us-gaap	Available For Sale Securities Equity Securities Current AvailableForSaleSecuritiesEquitySecuritiesCurrent	1823800000	USD
CY2016Q4	us-gaap	Available For Sale Securities Equity Securities Noncurrent AvailableForSaleSecuritiesEquitySecuritiesNoncurrent	31400000	USD
CY2017Q2	us-gaap	Available For Sale Securities Equity Securities Noncurrent AvailableForSaleSecuritiesEquitySecuritiesNoncurrent	32300000	USD
CY2016Q2	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	108400000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	229800000	USD
CY2017Q2	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	50900000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	110700000	USD
CY2016Q2	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	31000000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	123700000	USD
CY2017Q2	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	20100000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	50300000	USD
CY2016Q4	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	3330	securities
CY2017Q2	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	2626	securities
CY2016Q2	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	-153500000	USD
	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	-239100000	USD
CY2017Q2	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	-67000000	USD
	us-gaap	Available For Sale Securities Income Tax Expense On Change In Unrealized Holding Gain Or Loss AvailableForSaleSecuritiesIncomeTaxExpenseOnChangeInUnrealizedHoldingGainOrLoss	-113300000	USD
CY2016Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	425	securities
CY2017Q2	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	272	securities
CY2016Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	20007900000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	38984400000	USD
CY2017Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	21201500000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	42212400000	USD
CY2015Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	2113500000	USD
CY2016Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1582700000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	4075300000	USD
CY2017Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	4561200000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	1546000000	USD
CY2017Q2	us-gaap	Cash And Cash Equivalents Fair Value Disclosure CashAndCashEquivalentsFairValueDisclosure	2625200000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-530800000	USD
	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	485900000	USD
CY2015Q4	us-gaap	Ceded Premiums Payable CededPremiumsPayable	645600000	USD
CY2016Q2	us-gaap	Ceded Premiums Payable CededPremiumsPayable	587000000	USD
CY2016Q4	us-gaap	Ceded Premiums Payable CededPremiumsPayable	539100000	USD
CY2017Q2	us-gaap	Ceded Premiums Payable CededPremiumsPayable	491800000	USD
CY2016Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2017Q2	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2016Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.65
CY2016Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.65
CY2017Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.65
CY2017Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.65
CY2016Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.65
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.30
CY2017Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.65
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.30
CY2016Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2017Q2	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2016Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	900000000	shares
CY2017Q2	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	900000000	shares
CY2016Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	263747395	shares
CY2017Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	263095951	shares
CY2016Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	263747395	shares
CY2017Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	263095951	shares
CY2016Q4	us-gaap	Common Stock Value CommonStockValue	2600000	USD
CY2017Q2	us-gaap	Common Stock Value CommonStockValue	2600000	USD
CY2016Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	798100000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1411300000	USD
CY2017Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	882200000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1998200000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	99700000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-209900000	USD
CY2016Q2	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	35400000	USD
CY2017Q2	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	34400000	USD
CY2016Q2	us-gaap	Deferred Tax Assets Unrealized Currency Losses DeferredTaxAssetsUnrealizedCurrencyLosses	3100000	USD
CY2017Q2	us-gaap	Deferred Tax Assets Unrealized Currency Losses DeferredTaxAssetsUnrealizedCurrencyLosses	1100000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2779900000	USD
CY2017Q2	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	2632700000	USD
CY2016Q2	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax	-621500000	USD
CY2017Q2	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax	-641200000	USD
CY2016Q2	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax	100000	USD
CY2017Q2	us-gaap	Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax	700000	USD
CY2016Q4	us-gaap	Deposits Received For Securities Loaned At Carrying Value DepositsReceivedForSecuritiesLoanedAtCarryingValue	1078900000	USD
CY2017Q2	us-gaap	Deposits Received For Securities Loaned At Carrying Value DepositsReceivedForSecuritiesLoanedAtCarryingValue	1213700000	USD
	us-gaap	Depreciation Depreciation	51700000	USD
	us-gaap	Depreciation Depreciation	54500000	USD
CY2017Q2	us-gaap	Derivative Asset Collateral Obligation To Return Cash Offset DerivativeAssetCollateralObligationToReturnCashOffset	84800000	USD
CY2016Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	92800000	USD
CY2017Q2	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	147400000	USD
CY2016Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	758700000	USD
CY2017Q2	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	311700000	USD
CY2016Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	665900000	USD
CY2017Q2	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	164300000	USD
CY2016Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	241900000	USD
CY2017Q2	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	382200000	USD
CY2016Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	149100000	USD
CY2017Q2	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	234800000	USD
CY2016Q2	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-64900000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-218700000	USD
CY2017Q2	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-14600000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-24900000	USD
CY2017Q2	us-gaap	Derivative Liability Collateral Right To Reclaim Cash Offset DerivativeLiabilityCollateralRightToReclaimCashOffset	139600000	USD
CY2016Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	92800000	USD
CY2017Q2	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	147400000	USD
CY2016Q1	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2016-03-25
CY2016Q2	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2016-06-24
CY2017Q1	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2017-03-24
CY2017Q2	us-gaap	Dividend Payable Date To Be Paid Day Month And Year DividendPayableDateToBePaidDayMonthAndYear	2017-06-23
	us-gaap	Dividends Common Stock DividendsCommonStock	343700000	USD
	us-gaap	Dividends Common Stock DividendsCommonStock	344800000	USD
CY2016Q1	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2016-02-18
CY2016Q2	us-gaap	Dividends Payable Date Declared Day Month And Year DividendsPayableDateDeclaredDayMonthAndYear	2016-04-26
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
CY2016Q1	us-gaap	Dividends Payable Date Of Record Day Month And Year DividendsPayableDateOfRecordDayMonthAndYear	2016-03-10
CY2016Q2	us-gaap	Dividends Payable Date Of Record Day Month And Year DividendsPayableDateOfRecordDayMonthAndYear	2016-06-10
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
CY2016Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.97
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.65
CY2017Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.23
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	7.05
CY2016Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.91
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.54
CY2017Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.16
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.89
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	1000000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	2900000	USD
CY2016Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.461
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.463
CY2017Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.291
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.314
	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	46000000	USD
	us-gaap	Excess Tax Benefit From Share Based Compensation Financing Activities ExcessTaxBenefitFromShareBasedCompensationFinancingActivities	0	USD
	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	46000000	USD
	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	0	USD
CY2016Q2	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-100000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-1800000	USD
CY2017Q2	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-900000	USD
	us-gaap	Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss	-2600000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	600000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	400000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-600000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	1500000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-2000000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	600000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	3900000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	62000000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	164200000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	68000000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	149800000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	8900000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	12300000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	12000000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	46500000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	10300000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	21200000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	16800000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	37000000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	9800000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	21700000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	6300000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	15800000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	57200000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	59100000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	15200000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	46400000	USD
CY2015Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	315800000	USD
CY2016Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	411500000	USD
CY2016Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	407700000	USD
CY2016Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	481400000	USD
CY2017Q1	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	489100000	USD
CY2017Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	520400000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-600000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-400000	USD
CY2016Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	2617600000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	5467900000	USD
CY2017Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	2708300000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	5551000000	USD
CY2016Q4	us-gaap	Good Faith And Margin Deposits With Broker Dealers GoodFaithAndMarginDepositsWithBrokerDealers	405300000	USD
CY2017Q2	us-gaap	Good Faith And Margin Deposits With Broker Dealers GoodFaithAndMarginDepositsWithBrokerDealers	224800000	USD
CY2016Q4	us-gaap	Goodwill Goodwill	17561200000	USD
CY2017Q2	us-gaap	Goodwill Goodwill	17561200000	USD
CY2016Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1448300000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2760300000	USD
CY2017Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1205700000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2720700000	USD
CY2016Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1448300000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2760300000	USD
CY2017Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1205700000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	2720700000	USD
CY2016Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	667700000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1276700000	USD
CY2017Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	350400000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	855500000	USD
CY2016Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	104100000	USD
	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	208200000	USD
CY2017Q2	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	5200000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	25200000	USD
CY2016Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	168700000	USD
CY2017Q2	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	0	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	343100000	USD
	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-53000000	USD
	us-gaap	Increase Decrease In Collateral Held Under Securities Lending IncreaseDecreaseInCollateralHeldUnderSecuritiesLending	211200000	USD
	us-gaap	Increase Decrease In Collateral Held Under Securities Lending IncreaseDecreaseInCollateralHeldUnderSecuritiesLending	134800000	USD
	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	338200000	USD
	us-gaap	Increase Decrease In Income Taxes Payable Net Of Income Taxes Receivable IncreaseDecreaseInIncomeTaxesPayableNetOfIncomeTaxesReceivable	281700000	USD
	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	54100000	USD
	us-gaap	Increase Decrease In Insurance Liabilities IncreaseDecreaseInInsuranceLiabilities	254000000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	284500000	USD
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	322400000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	22300000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	43400000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-17100000	USD
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	81500000	USD
	us-gaap	Increase Decrease In Outstanding Checks Financing Activities IncreaseDecreaseInOutstandingChecksFinancingActivities	15200000	USD
	us-gaap	Increase Decrease In Outstanding Checks Financing Activities IncreaseDecreaseInOutstandingChecksFinancingActivities	-146200000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	332800000	USD
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	134700000	USD
	us-gaap	Increase Decrease In Securities Lending Payable IncreaseDecreaseInSecuritiesLendingPayable	211100000	USD
	us-gaap	Increase Decrease In Securities Lending Payable IncreaseDecreaseInSecuritiesLendingPayable	134800000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	13200000	USD
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	22400000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	-312700000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	865900000	USD
CY2016Q2	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	21274500000	USD
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	41583900000	USD
CY2017Q2	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	22198000000	USD
	us-gaap	Insurance Services Revenue InsuranceServicesRevenue	44517500000	USD
CY2016Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	7964900000	USD
CY2017Q2	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	7882400000	USD
CY2016Q2	us-gaap	Interest Expense InterestExpense	185700000	USD
	us-gaap	Interest Expense InterestExpense	372800000	USD
CY2017Q2	us-gaap	Interest Expense InterestExpense	189900000	USD
	us-gaap	Interest Expense InterestExpense	424900000	USD
CY2016Q4	us-gaap	Liabilities Liabilities	39982700000	USD
CY2017Q2	us-gaap	Liabilities Liabilities	41805900000	USD
CY2016Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	65083100000	USD
CY2017Q2	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	68237600000	USD
CY2016Q4	us-gaap	Liabilities Current LiabilitiesCurrent	21294400000	USD
CY2017Q2	us-gaap	Liabilities Current LiabilitiesCurrent	22567900000	USD
CY2016Q4	us-gaap	Liabilities Fair Value Disclosure Recurring LiabilitiesFairValueDisclosureRecurring	241900000	USD
CY2017Q2	us-gaap	Liabilities Fair Value Disclosure Recurring LiabilitiesFairValueDisclosureRecurring	382200000	USD
CY2015Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7569800000	USD
CY2016Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7498600000	USD
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7892600000	USD
CY2017Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	7969500000	USD
CY2016Q4	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	666100000	USD
CY2017Q2	us-gaap	Liability For Future Policy Benefits LiabilityForFuturePolicyBenefits	619000000	USD
CY2016Q4	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	10185500000	USD
CY2017Q2	us-gaap	Liability For Future Policy Benefits And Unpaid Claims And Claims Adjustment Expense LiabilityForFuturePolicyBenefitsAndUnpaidClaimsAndClaimsAdjustmentExpense	10486600000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	26197100000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	28540400000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	5541400000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	6070900000	USD
CY2016Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	16500700000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	31725900000	USD
CY2017Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	17561600000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	34735500000	USD
CY2015Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	6924200000	USD
CY2016Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	6911600000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7353500000	USD
CY2017Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	7477700000	USD
CY2017Q2	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	3500000000	USD
	us-gaap	Litigation Settlement Amount Awarded To Other Party LitigationSettlementAmountAwardedToOtherParty	115000000	USD
CY2016Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	928400000	USD
CY2017Q2	us-gaap	Long Term Debt Current LongTermDebtCurrent	624400000	USD
CY2016Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	14358500000	USD
CY2017Q2	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	15088000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-853400000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-329500000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1707800000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2268800000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2029400000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3081300000	USD
CY2016Q2	us-gaap	Net Income Loss NetIncomeLoss	780600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	1483600000	USD
CY2017Q2	us-gaap	Net Income Loss NetIncomeLoss	855300000	USD
	us-gaap	Net Income Loss NetIncomeLoss	1865200000	USD
CY2016Q2	us-gaap	Net Investment Income NetInvestmentIncome	194900000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	366000000	USD
CY2017Q2	us-gaap	Net Investment Income NetInvestmentIncome	200200000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	407400000	USD
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	segment
CY2017Q2	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	50	states
CY2016Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	1500200000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	3070600000	USD
CY2017Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	1227000000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	2812400000	USD
CY2016Q4	us-gaap	Other Assets Current OtherAssetsCurrent	1781800000	USD
CY2017Q2	us-gaap	Other Assets Current OtherAssetsCurrent	1774600000	USD
CY2016Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	467900000	USD
CY2017Q2	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	778400000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	243400000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	390900000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	116200000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	210400000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-700000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	600000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	700000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	2100000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	500000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-200000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-400000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	-1100000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	17500000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-72300000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	26900000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	133000000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	17500000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-72300000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	26900000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	133000000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-3800000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-7600000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-4200000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-8100000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	33600000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	8800000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	15300000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	29300000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-18100000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-4700000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-8300000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-15800000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-32400000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	9600000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-25800000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-72400000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-190000000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-455500000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-79800000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-62800000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	102400000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	245300000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	36600000	USD
	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	33900000	USD
CY2016Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	209800000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	382100000	USD
CY2017Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	100900000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	181100000	USD
CY2016Q2	us-gaap	Other Income OtherIncome	10700000	USD
	us-gaap	Other Income OtherIncome	20200000	USD
CY2017Q2	us-gaap	Other Income OtherIncome	6000000	USD
	us-gaap	Other Income OtherIncome	11000000	USD
CY2016Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	3581300000	USD
CY2017Q2	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	3668900000	USD
CY2016Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	883800000	USD
CY2017Q2	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	898300000	USD
CY2016Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	2240500000	USD
CY2017Q2	us-gaap	Other Long Term Investments OtherLongTermInvestments	2352100000	USD
CY2016Q4	us-gaap	Other Policyholder Funds OtherPolicyholderFunds	2221100000	USD
CY2017Q2	us-gaap	Other Policyholder Funds OtherPolicyholderFunds	2447500000	USD
CY2016Q4	us-gaap	Other Receivables OtherReceivables	2536600000	USD
CY2017Q2	us-gaap	Other Receivables OtherReceivables	2525400000	USD
CY2016Q4	us-gaap	Other Short Term Investments OtherShortTermInvestments	15800000	USD
CY2017Q2	us-gaap	Other Short Term Investments OtherShortTermInvestments	19100000	USD
CY2016Q2	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	5400000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	7100000	USD
CY2017Q2	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	-900000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Period Increase Decrease OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsPeriodIncreaseDecrease	-4500000	USD
CY2016Q2	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	33800000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	119000000	USD
CY2017Q2	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	7300000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities	16900000	USD
CY2016Q2	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	-8100000	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	-26400000	USD
CY2017Q2	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	-100000	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	-1600000	USD
CY2016Q2	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	5400000	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	7100000	USD
CY2017Q2	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	-900000	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	-4500000	USD
CY2016Q2	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	2700000	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	3900000	USD
CY2017Q2	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-400000	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	-2500000	USD
CY2016Q2	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	25700000	USD

CY2016Q2

antm

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

AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax

-8700000

USD

CY2017Q2

antm

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

AccumulatedOtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax

-3100000

USD

CY2016Q2

antm

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

AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability

-358600000

USD

CY2017Q2

antm

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

AvailableForSaleSecuritiesAccumulatedOtherComprehensiveIncomeNetDeferredTaxLiability

-304000000

USD

CY2016Q4

antm

Available For Sale Securities Debt Maturities Amortized Cost Noncurrent

AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent

524600000

USD

CY2017Q2

antm

Available For Sale Securities Debt Maturities Amortized Cost Noncurrent

AvailableForSaleSecuritiesDebtMaturitiesAmortizedCostNoncurrent

516700000

USD

CY2016Q4

antm

Available For Sale Securities Equity Securities Cost Current

AvailableForSaleSecuritiesEquitySecuritiesCostCurrent

1076100000

USD

CY2017Q2

antm

Available For Sale Securities Equity Securities Cost Current

AvailableForSaleSecuritiesEquitySecuritiesCostCurrent

1378300000

USD

CY2016Q4

antm

Available For Sale Securities Equity Securities Cost Noncurrent

AvailableForSaleSecuritiesEquitySecuritiesCostNoncurrent

27200000

USD

CY2017Q2

antm

Available For Sale Securities Equity Securities Cost Noncurrent

AvailableForSaleSecuritiesEquitySecuritiesCostNoncurrent

27300000

USD

CY2017Q2

antm

Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset

AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset

100000

USD

CY2016Q2

antm

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

CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset

289000000

USD

CY2016Q2

antm

Available For Sale Securities Other Than Temporary Impairments In Accumulated Other Comprehensive Income Deferred Tax Liability Asset

AvailableForSaleSecuritiesOtherThanTemporaryImpairmentsInAccumulatedOtherComprehensiveIncomeDeferredTaxLiabilityAsset

9300000

USD

CY2017Q2

antm

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

CashFlowHedgingInstrumentsAccumulatedOtherComprehensiveIncomeNetDeferredTaxAsset

124600000

USD

CY2016Q2

antm

Deferred Net Actuarial Gain Loss Postretirement Benefits

DeferredNetActuarialGainLossPostretirementBenefits

-156500000

USD

CY2017Q2

antm

Deferred Net Actuarial Gain Loss Postretirement Benefits

DeferredNetActuarialGainLossPostretirementBenefits

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CY2016Q2

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CY2017Q2

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CY2016Q2

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Gross Premium Tax Rate

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CY2017Q2

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Merger Agreement Termination Fee

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CY2016Q2

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Potentially Dilutive Restricted Stock Units Contingent On Operating Results

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Present Value Of Contract Liability Debt Issuance Costs Related To Equity Units

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Securities Lending Transactions Initial Collateral Percentage Value

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Securities Lending Transactions Initial Collateral Percentage Value

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

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

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Entity Filer Category

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Entity Registrant Name

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CY2017Q3

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us-gaap

Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits

DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits

35400000

USD

CY2017Q2

us-gaap

Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits

DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits

34400000

USD

CY2016Q2

us-gaap

Deferred Tax Assets Unrealized Currency Losses

DeferredTaxAssetsUnrealizedCurrencyLosses

3100000

USD

CY2017Q2

us-gaap

Deferred Tax Assets Unrealized Currency Losses

DeferredTaxAssetsUnrealizedCurrencyLosses

1100000

USD

CY2016Q4

us-gaap

Deferred Tax Liabilities Noncurrent

DeferredTaxLiabilitiesNoncurrent

2779900000

USD

CY2017Q2

us-gaap

Deferred Tax Liabilities Noncurrent

DeferredTaxLiabilitiesNoncurrent

2632700000

USD

CY2016Q2

us-gaap

Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax

DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax

-621500000

USD

CY2017Q2

us-gaap

Defined Benefit Plan Accumulated Other Comprehensive Income Net Gains Losses Before Tax

DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax

-641200000

USD

CY2016Q2

us-gaap

Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax

DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

100000

USD

CY2017Q2

us-gaap

Defined Benefit Plan Accumulated Other Comprehensive Income Net Prior Service Cost Credit Before Tax

DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax

700000

USD

CY2016Q4

us-gaap

Deposits Received For Securities Loaned At Carrying Value

DepositsReceivedForSecuritiesLoanedAtCarryingValue

1078900000

USD

CY2017Q2

us-gaap

Deposits Received For Securities Loaned At Carrying Value

DepositsReceivedForSecuritiesLoanedAtCarryingValue

1213700000

USD

us-gaap

Depreciation

51700000

USD

us-gaap

Depreciation

54500000

USD

CY2017Q2

us-gaap

Derivative Asset Collateral Obligation To Return Cash Offset

DerivativeAssetCollateralObligationToReturnCashOffset

84800000

USD

CY2016Q4

us-gaap

Derivative Asset Fair Value Gross Liability

DerivativeAssetFairValueGrossLiability

92800000

USD

CY2017Q2

us-gaap

Derivative Asset Fair Value Gross Liability

DerivativeAssetFairValueGrossLiability

147400000

USD

CY2016Q4

us-gaap

Derivative Fair Value Of Derivative Asset

DerivativeFairValueOfDerivativeAsset

758700000

USD

CY2017Q2

us-gaap

Derivative Fair Value Of Derivative Asset

DerivativeFairValueOfDerivativeAsset

311700000

USD

CY2016Q4

us-gaap

Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral

DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral

665900000

USD

CY2017Q2

us-gaap

Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral

DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral

164300000

USD

CY2016Q4

us-gaap

Derivative Fair Value Of Derivative Liability

DerivativeFairValueOfDerivativeLiability

241900000

USD

CY2017Q2

us-gaap

Derivative Fair Value Of Derivative Liability

DerivativeFairValueOfDerivativeLiability

382200000

USD

CY2016Q4

us-gaap

Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral

DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral

149100000

USD

CY2017Q2

us-gaap

Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral

DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral

234800000

USD

CY2016Q2

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-64900000

USD

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-218700000

USD

CY2017Q2

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-14600000

USD

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-24900000

USD

CY2017Q2

us-gaap

Derivative Liability Collateral Right To Reclaim Cash Offset

DerivativeLiabilityCollateralRightToReclaimCashOffset

139600000

USD

CY2016Q4

us-gaap

Derivative Liability Fair Value Gross Asset

DerivativeLiabilityFairValueGrossAsset

92800000

USD

CY2017Q2

us-gaap

Derivative Liability Fair Value Gross Asset

DerivativeLiabilityFairValueGrossAsset

147400000

USD

CY2016Q1

us-gaap

Dividend Payable Date To Be Paid Day Month And Year

DividendPayableDateToBePaidDayMonthAndYear

2016-03-25

CY2016Q2

us-gaap

Dividend Payable Date To Be Paid Day Month And Year

DividendPayableDateToBePaidDayMonthAndYear

2016-06-24

CY2017Q1

us-gaap

Dividend Payable Date To Be Paid Day Month And Year

DividendPayableDateToBePaidDayMonthAndYear

2017-03-24

CY2017Q2

us-gaap

Dividend Payable Date To Be Paid Day Month And Year

DividendPayableDateToBePaidDayMonthAndYear

2017-06-23

us-gaap

Dividends Common Stock

DividendsCommonStock

343700000

USD

us-gaap

Dividends Common Stock

DividendsCommonStock

344800000

USD

CY2016Q1

us-gaap

Dividends Payable Date Declared Day Month And Year

DividendsPayableDateDeclaredDayMonthAndYear

2016-02-18

CY2016Q2

us-gaap

Dividends Payable Date Declared Day Month And Year

DividendsPayableDateDeclaredDayMonthAndYear

2016-04-26

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

CY2016Q1

us-gaap

Dividends Payable Date Of Record Day Month And Year

DividendsPayableDateOfRecordDayMonthAndYear

2016-03-10

CY2016Q2

us-gaap

Dividends Payable Date Of Record Day Month And Year

DividendsPayableDateOfRecordDayMonthAndYear

2016-06-10

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

CY2016Q2

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

2.97

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

5.65

CY2017Q2

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

3.23

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

7.05

CY2016Q2

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

2.91

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

5.54

CY2017Q2

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

3.16

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

6.89

us-gaap

Effect Of Exchange Rate On Cash And Cash Equivalents

EffectOfExchangeRateOnCashAndCashEquivalents

1000000

USD

us-gaap

Effect Of Exchange Rate On Cash And Cash Equivalents

EffectOfExchangeRateOnCashAndCashEquivalents

2900000

USD

CY2016Q2

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.461

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.463

CY2017Q2

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.291

us-gaap

Effective Income Tax Rate Continuing Operations

EffectiveIncomeTaxRateContinuingOperations

0.314

us-gaap

Excess Tax Benefit From Share Based Compensation Financing Activities

ExcessTaxBenefitFromShareBasedCompensationFinancingActivities

46000000

USD

us-gaap

Excess Tax Benefit From Share Based Compensation Financing Activities

ExcessTaxBenefitFromShareBasedCompensationFinancingActivities

0

USD

us-gaap

Excess Tax Benefit From Share Based Compensation Operating Activities

ExcessTaxBenefitFromShareBasedCompensationOperatingActivities

46000000

USD

us-gaap

Excess Tax Benefit From Share Based Compensation Operating Activities

ExcessTaxBenefitFromShareBasedCompensationOperatingActivities

0

USD

CY2016Q2

us-gaap

Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

-100000

USD

us-gaap

Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

-1800000

USD

CY2017Q2

us-gaap

Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

-900000

USD

us-gaap

Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

-2600000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

-700000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

600000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

400000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

-600000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

1500000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

-2000000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

600000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

3900000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

62000000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

164200000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

68000000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

149800000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

8900000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

12300000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

12000000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

46500000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

10300000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

21200000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

16800000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

37000000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

9800000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

21700000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

6300000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

15800000

USD

CY2016Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

57200000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

59100000

USD

CY2017Q2

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

15200000

USD

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

46400000

USD

CY2015Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value