$AIZ
ASSURANT, INC. Stock $aiz

$aiz Overview Financials Valuation SEC Filings Company Website

2017 Form 10-K Financial Statement

#000162828018001695 Filed on February 14, 2018

Income Statement

Concept	2017	2016 Q4	2016 Q3
Revenue	$6.415B	$1.752B	$1.834B
YoY Change	-14.83%	-31.22%	-27.62%
Cost Of Revenue	$1.871B		$435.2M
YoY Change	3.43%		-65.3%
Gross Profit	$4.544B		$1.399B
YoY Change	-20.6%		9.29%
Gross Profit Margin	70.84%		76.27%
Selling, General & Admin	$2.710B	$888.0M	$833.7M
YoY Change	-21.27%	-17.45%	-12.88%
% of Gross Profit	59.64%		59.6%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$34.20M
YoY Change	-17.99%
% of Gross Profit	0.75%
Operating Expenses	$2.710B	$1.661B	$833.7M
YoY Change	-21.27%	-31.49%	-12.88%
Operating Profit	$1.834B		$565.2M
YoY Change	-19.58%		75.0%
Interest Expense	$49.50M	-$13.90M	$14.00M
YoY Change	-14.06%	0.72%	1.6%
% of Operating Profit	2.7%		2.48%
Other Income/Expense, Net
YoY Change
Pretax Income	$444.5M	$54.60M	$220.9M
YoY Change	-47.62%	-50.46%	-784.94%
Income Tax	-$75.10M	$23.40M	$76.50M
% Of Pretax Income	-16.9%	42.86%	34.63%
Net Earnings	$519.6M	$31.30M	$144.4M
YoY Change	-8.1%	-52.39%	-2156.39%
Net Earnings / Revenue	8.1%	1.79%	7.87%
Basic Earnings Per Share	$9.45	$0.54	$2.40
Diluted Earnings Per Share	$9.39	$0.54	$2.37
COMMON SHARES
Basic Shares Outstanding	54.99M shares	57.01M shares	60.26M shares
Diluted Shares Outstanding	55.31M shares		60.83M shares

Balance Sheet

Concept	2017	2016 Q4	2016 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$997.0M	$1.032B	$1.117B
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$348.0M	$343.6M	$337.1M
YoY Change	1.16%	15.14%	17.56%
Goodwill		$830.9M	$839.7M
YoY Change		-0.31%	-0.18%
Intangibles		$240.3M	$263.3M
YoY Change		-13.3%	-12.47%
Long-Term Investments	$12.30B	$11.44B	$11.99B
YoY Change	7.51%	-11.66%	-10.87%
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$31.84B	$29.71B	$30.28B
YoY Change	7.18%	-1.09%	-0.99%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$2.046B	$1.986B	$2.009B
YoY Change	3.02%	-3.12%	-8.22%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$6.193B	$5.674B	$5.846B
YoY Change	9.15%	-10.5%	-12.81%
LONG-TERM LIABILITIES
Long-Term Debt	$1.068B	$1.067B	$1.166B
YoY Change	0.09%	-8.41%	-0.43%
Other Long-Term Liabilities	$702.0M	$232.0M	$318.0M
YoY Change	202.59%	152.17%	123.94%
Total Long-Term Liabilities	$1.770B	$1.299B	$1.484B
YoY Change	36.26%	3.34%	13.02%
TOTAL LIABILITIES
Total Short-Term Liabilities	$6.193B	$5.674B	$5.846B
Total Long-Term Liabilities	$1.770B	$1.299B	$1.484B
Total Liabilities	$27.57B	$25.61B	$25.78B
YoY Change	7.66%	0.39%	-0.48%
SHAREHOLDERS EQUITY
Retained Earnings		$5.297B	$5.296B
YoY Change		9.06%	9.77%
Common Stock		$3.177B	$3.170B
YoY Change		0.87%	0.94%
Preferred Stock
YoY Change
Treasury Stock (at cost)		$4.471B	$4.289B
YoY Change		24.14%	21.6%
Treasury Stock Shares		94.04M shares	91.95M shares
Shareholders Equity	$4.271B	$4.098B	$4.505B
YoY Change
Total Liabilities & Shareholders Equity	$31.84B	$29.71B	$30.28B
YoY Change	7.18%	-1.09%	-0.99%

Cashflow Statement

Concept	2017	2016 Q4	2016 Q3
OPERATING ACTIVITIES
Net Income	$519.6M	$31.30M	$144.4M
YoY Change	-8.1%	-52.39%	-2156.39%
Depreciation, Depletion And Amortization	$34.20M
YoY Change	-17.99%
Cash From Operating Activities	$530.4M	$151.7M	$258.6M
YoY Change	388.4%	-152.01%	-25.43%
INVESTING ACTIVITIES
Capital Expenditures	$62.10M	-$18.40M	-$19.10M
YoY Change	-27.11%	-27.84%	-29.52%
Acquisitions	$129.1M
YoY Change	104.27%
Other Investing Activities	-$4.700M	$112.7M	-$95.30M
YoY Change	-7.84%	-48.63%	-327.99%
Cash From Investing Activities	-$541.2M	$94.30M	-$114.3M
YoY Change	-174.59%	-51.37%	-882.88%
FINANCING ACTIVITIES
Cash Dividend Paid	$119.0M
YoY Change	-5.03%
Common Stock Issuance & Retirement, Net	$388.9M
YoY Change	-54.94%
Debt Paid & Issued, Net	$0.00
YoY Change
Cash From Financing Activities	-$26.70M	-320.0M	-257.3M
YoY Change	-97.53%	133.41%	171.13%
NET CHANGE
Cash From Operating Activities	$530.4M	151.7M	258.6M
Cash From Investing Activities	-$541.2M	94.30M	-114.3M
Cash From Financing Activities	-$26.70M	-320.0M	-257.3M
Net Change In Cash	-$35.20M	-74.00M	-113.0M
YoY Change	-85.7%	-68.5%	-142.4%
FREE CASH FLOW
Cash From Operating Activities	$530.4M	$151.7M	$258.6M
Capital Expenditures	$62.10M	-$18.40M	-$19.10M
Free Cash Flow	$468.3M	$170.1M	$277.7M
YoY Change	1901.28%	-163.9%	-25.73%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2016	aiz	Forfeiture Rate ForfeitureRate	0.05
CY2017	aiz	Lender Placed Insurance Rate Refile Period LenderPlacedInsuranceRateRefilePeriod	P4Y
CY2017	aiz	Length Of Averaging Method Used To Determine Market Related Value Of Plan Assets LengthOfAveragingMethodUsedToDetermineMarketRelatedValueOfPlanAssets	P5Y
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CY2016	aiz	Non Income Producing Material Investments NonIncomeProducingMaterialInvestments	0	USD
CY2017	dei	Amendment Flag AmendmentFlag	false
CY2017	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2017	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2017	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2017
CY2017	dei	Document Period End Date DocumentPeriodEndDate	2017-12-31
CY2017	dei	Document Type DocumentType	10-K
CY2017	dei	Entity Central Index Key EntityCentralIndexKey	0001267238
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CY2017	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2017	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2017Q2	dei	Entity Public Float EntityPublicFloat	5560000000	USD
CY2017	dei	Entity Registrant Name EntityRegistrantName	ASSURANT INC
CY2017	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2017	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2017	dei	Trading Symbol TradingSymbol	AIZ
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CY2017	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	900000	USD
CY2016	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	6900000	USD
CY2015	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	5000000.0	USD
CY2017	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	103900000	USD
CY2016	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	394500000	USD
CY2015	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	13000000.0	USD
CY2017	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	0	USD
CY2016	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	29600000	USD
CY2015	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	0	USD
CY2017	us-gaap	Revenues Revenues	6415000000.0	USD
CY2016	us-gaap	Revenues Revenues	7531800000	USD
CY2015	us-gaap	Revenues Revenues	10325500000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1870600000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1808500000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4742500000	USD
CY2017	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1340000000.0	USD
CY2016	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1351300000	USD
CY2015	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1402600000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	2710400000	USD
CY2016	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	3442800000	USD
CY2015	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	3924100000	USD
CY2017	us-gaap	Interest Expense InterestExpense	49500000	USD
CY2016	us-gaap	Interest Expense InterestExpense	57600000	USD
CY2015	us-gaap	Interest Expense InterestExpense	55100000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2016	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-23000000.0	USD
CY2015	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2017	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	5970500000	USD
CY2016	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	6683200000	USD
CY2015	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	10124300000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	444500000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	848600000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	201200000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-75100000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	283200000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59600000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.45
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.23
CY2015	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.08
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.39
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.13
CY2015	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.05
CY2017	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.15
CY2016	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.03
CY2015	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.37
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54986654	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	61261288	shares
CY2015	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	68163825	shares
CY2017	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	324378	shares
CY2016	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	673486	shares
CY2015	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	853384	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55311032	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	61934774	shares
CY2015	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	69017209	shares
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	121900000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-36200000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-297600000	USD
CY2017	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	2700000	USD
CY2016	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	1800000	USD
CY2015	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	4200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	40600000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-51400000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-143000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	20400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-65400000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-7600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	139400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-24000000.0	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-437200000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	659000000.0	USD
CY2016	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	541400000	USD
CY2015	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-295600000	USD
CY2014Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	5181300000	USD
CY2015	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-17500000	USD
CY2015	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	38800000	USD
CY2015	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	-4100000	USD
CY2015	us-gaap	Dividends Cash DividendsCash	94200000	USD
CY2015	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	284700000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-437200000	USD
CY2015Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4524000000.0	USD
CY2016	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-19800000	USD
CY2016	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	41700000	USD
CY2016	us-gaap	Adjustment To Additional Paid In Capital Income Tax Effect From Share Based Compensation Net AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet	5600000	USD
CY2016	us-gaap	Dividends Cash DividendsCash	125400000	USD
CY2016	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	869400000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-24000000.0	USD
CY2015	aiz	Noncash Receivable Payable Resultingfrom Health Care Regulations NoncashReceivablePayableResultingfromHealthCareRegulations	-136600000	USD
CY2017	aiz	Change In Insurance Policy Reserves And Expenses ChangeInInsurancePolicyReservesAndExpenses	1388200000	USD
CY2016	aiz	Change In Insurance Policy Reserves And Expenses ChangeInInsurancePolicyReservesAndExpenses	197300000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4098100000	USD
CY2017	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-13500000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	35500000	USD
CY2017	us-gaap	Dividends Cash DividendsCash	119000000.0	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	389500000	USD
CY2017	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	10900000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	139400000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4281500000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4200000	USD
CY2016	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	25000000.0	USD
CY2015	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-3900000	USD
CY2017	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	103900000	USD
CY2016	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	394500000	USD
CY2015	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	13000000.0	USD
CY2017	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	115700000	USD
CY2016	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	125100000	USD
CY2015	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	137100000	USD
CY2017	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	30100000	USD
CY2016	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	162200000	USD
CY2015	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	31800000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2016	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-23000000.0	USD
CY2015	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	35500000	USD
CY2016	us-gaap	Share Based Compensation ShareBasedCompensation	41600000	USD
CY2015	us-gaap	Share Based Compensation ShareBasedCompensation	38800000	USD
CY2017	aiz	Income Loss On Sale Of Real Estate Joint Ventures IncomeLossOnSaleOfRealEstateJointVentures	14700000	USD
CY2016	aiz	Income Loss On Sale Of Real Estate Joint Ventures IncomeLossOnSaleOfRealEstateJointVentures	15700000	USD
CY2015	aiz	Income Loss On Sale Of Real Estate Joint Ventures IncomeLossOnSaleOfRealEstateJointVentures	23600000	USD
CY2017	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	0	USD
CY2016	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	29600000	USD
CY2015	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	0	USD
CY2017	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	2000000.0	USD
CY2016	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	16100000	USD
CY2015	us-gaap	Impairment Of Intangible Assets Excluding Goodwill ImpairmentOfIntangibleAssetsExcludingGoodwill	1000000.0	USD
CY2017	aiz	Noncash Receivable Payable Resultingfrom Health Care Regulations NoncashReceivablePayableResultingfromHealthCareRegulations	30300000	USD
CY2016	aiz	Noncash Receivable Payable Resultingfrom Health Care Regulations NoncashReceivablePayableResultingfromHealthCareRegulations	487600000	USD
CY2017	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	936100000	USD
CY2015	aiz	Change In Insurance Policy Reserves And Expenses ChangeInInsurancePolicyReservesAndExpenses	454200000	USD
CY2016	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	240600000	USD
CY2017	aiz	Change In Premiums And Accounts Receivable ChangeInPremiumsAndAccountsReceivable	10300000	USD
CY2016	aiz	Change In Premiums And Accounts Receivable ChangeInPremiumsAndAccountsReceivable	212500000	USD
CY2015	aiz	Change In Premiums And Accounts Receivable ChangeInPremiumsAndAccountsReceivable	-185600000	USD
CY2015	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	155700000	USD
CY2017	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	52500000	USD
CY2016	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	-41100000	USD
CY2015	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	-13700000	USD
CY2017	us-gaap	Increase Decrease In Funds Held Under Reinsurance Agreements IncreaseDecreaseInFundsHeldUnderReinsuranceAgreements	-64600000	USD
CY2016	us-gaap	Increase Decrease In Funds Held Under Reinsurance Agreements IncreaseDecreaseInFundsHeldUnderReinsuranceAgreements	-15900000	USD
CY2015	us-gaap	Increase Decrease In Funds Held Under Reinsurance Agreements IncreaseDecreaseInFundsHeldUnderReinsuranceAgreements	-26500000	USD
CY2017	aiz	Change In Deferred Acquisition Costs And Value Of Business Acquired ChangeInDeferredAcquisitionCostsAndValueOfBusinessAcquired	358800000	USD
CY2016	aiz	Change In Deferred Acquisition Costs And Value Of Business Acquired ChangeInDeferredAcquisitionCostsAndValueOfBusinessAcquired	229500000	USD
CY2015	aiz	Change In Deferred Acquisition Costs And Value Of Business Acquired ChangeInDeferredAcquisitionCostsAndValueOfBusinessAcquired	234700000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-7400000	USD
CY2016	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-4600000	USD
CY2015	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	27300000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-35300000	USD
CY2016	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-62800000	USD
CY2015	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-165000000.0	USD
CY2017	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-105500000	USD
CY2016	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	7200000	USD
CY2015	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-15900000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	86500000	USD
CY2016	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	11700000	USD
CY2015	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-66300000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	530400000	USD
CY2016	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	108600000	USD
CY2015	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	229900000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2923100000	USD
CY2016	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2963500000	USD
CY2015	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2380800000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	97500000	USD
CY2016	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	223300000	USD
CY2015	us-gaap	Proceeds From Sale Of Available For Sale Securities Equity ProceedsFromSaleOfAvailableForSaleSecuritiesEquity	181900000	USD
CY2017	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	62800000	USD
CY2016	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	82100000	USD
CY2015	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	68500000	USD
CY2017	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	26200000	USD
CY2016	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2015	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2016	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	873900000	USD
CY2015	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	49900000	USD
CY2017	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	0	USD
CY2016	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	268800000	USD
CY2015	us-gaap	Proceeds From Sale And Collection Of Mortgage Notes Receivable ProceedsFromSaleAndCollectionOfMortgageNotesReceivable	0	USD
CY2017	aiz	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities Debt ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecuritiesDebt	831900000	USD
CY2016	aiz	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities Debt ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecuritiesDebt	739000000.0	USD
CY2015	aiz	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities Debt ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecuritiesDebt	665500000	USD
CY2017	aiz	Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate	122700000	USD
CY2016	aiz	Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate	120700000	USD
CY2015	aiz	Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate Proceedsfrommaturitiesprepaymentsandcallsofcommercialmortgageloansonrealestate	253400000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	3547200000	USD
CY2016	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	4260000000.0	USD
CY2015	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2747400000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	24400000	USD
CY2016	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	200500000	USD
CY2015	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	185000000.0	USD
CY2017	aiz	Payments To Acquire Commercial Mortgage Loans On Real Estate PaymentsToAcquireCommercialMortgageLoansOnRealEstate	165000000.0	USD
CY2016	aiz	Payments To Acquire Commercial Mortgage Loans On Real Estate PaymentsToAcquireCommercialMortgageLoansOnRealEstate	116600000	USD
CY2015	aiz	Payments To Acquire Commercial Mortgage Loans On Real Estate PaymentsToAcquireCommercialMortgageLoansOnRealEstate	149000000.0	USD
CY2017	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	46500000	USD
CY2016	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	98500000	USD
CY2015	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	29300000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	62100000	USD
CY2016	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	85200000	USD
CY2015	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	114900000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	129100000	USD
CY2016	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	63200000	USD
CY2015	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	16900000	USD
CY2017	aiz	Purchasesof Investmentsby Special Purpose Entities PurchasesofInvestmentsbySpecialPurposeEntities	663800000	USD
CY2016	aiz	Purchasesof Investmentsby Special Purpose Entities PurchasesofInvestmentsbySpecialPurposeEntities	0	USD
CY2015	aiz	Purchasesof Investmentsby Special Purpose Entities PurchasesofInvestmentsbySpecialPurposeEntities	0	USD
CY2017	aiz	Sale Of Investments By Special Purpose Entities SaleOfInvestmentsBySpecialPurposeEntities	81900000	USD
CY2016	aiz	Sale Of Investments By Special Purpose Entities SaleOfInvestmentsBySpecialPurposeEntities	0	USD
CY2015	aiz	Sale Of Investments By Special Purpose Entities SaleOfInvestmentsBySpecialPurposeEntities	0	USD
CY2017	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	53900000	USD
CY2016	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-273200000	USD
CY2015	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	196700000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-4700000	USD
CY2016	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5100000	USD
CY2015	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-103500000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-541200000	USD
CY2016	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	725600000	USD
CY2015	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	264300000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2016	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	249600000	USD
CY2015	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2017	us-gaap	Repayments Of Debt RepaymentsOfDebt	0	USD
CY2016	us-gaap	Repayments Of Debt RepaymentsOfDebt	373000000.0	USD
CY2015	us-gaap	Repayments Of Debt RepaymentsOfDebt	0	USD
CY2017	us-gaap	Proceeds From Issuance Of Other Long Term Debt ProceedsFromIssuanceOfOtherLongTermDebt	368000000.0	USD
CY2016	us-gaap	Proceeds From Issuance Of Other Long Term Debt ProceedsFromIssuanceOfOtherLongTermDebt	0	USD
CY2015	us-gaap	Proceeds From Issuance Of Other Long Term Debt ProceedsFromIssuanceOfOtherLongTermDebt	0	USD
CY2017	aiz	Special Purpose Entity Proceeds From Issuance Of Long Term Debt SpecialPurposeEntityProceedsFromIssuanceOfLongTermDebt	303900000	USD
CY2016	aiz	Special Purpose Entity Proceeds From Issuance Of Long Term Debt SpecialPurposeEntityProceedsFromIssuanceOfLongTermDebt	0	USD
CY2015	aiz	Special Purpose Entity Proceeds From Issuance Of Long Term Debt SpecialPurposeEntityProceedsFromIssuanceOfLongTermDebt	0	USD
CY2017	aiz	Special Purpose Entity Repaymentsof Debt SpecialPurposeEntityRepaymentsofDebt	221100000	USD
CY2016	aiz	Special Purpose Entity Repaymentsof Debt SpecialPurposeEntityRepaymentsofDebt	0	USD
CY2015	aiz	Special Purpose Entity Repaymentsof Debt SpecialPurposeEntityRepaymentsofDebt	0	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	388900000	USD
CY2016	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	863100000	USD
CY2015	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	292900000	USD
CY2017	us-gaap	Payments Of Dividends PaymentsOfDividends	119000000.0	USD
CY2016	us-gaap	Payments Of Dividends PaymentsOfDividends	125300000	USD
CY2015	us-gaap	Payments Of Dividends PaymentsOfDividends	94200000	USD
CY2017	us-gaap	Proceeds And Excess Tax Benefit From Sharebased Compensation ProceedsAndExcessTaxBenefitFromSharebasedCompensation	19500000	USD
CY2016	us-gaap	Proceeds And Excess Tax Benefit From Sharebased Compensation ProceedsAndExcessTaxBenefitFromSharebasedCompensation	26000000.0	USD
CY2015	us-gaap	Proceeds And Excess Tax Benefit From Sharebased Compensation ProceedsAndExcessTaxBenefitFromSharebasedCompensation	24700000	USD
CY2017	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	10900000	USD
CY2016	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2015	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	0	USD
CY2016	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	5500000	USD
CY2015	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-100000000.0	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-26700000	USD
CY2016	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1080300000	USD
CY2015	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-462400000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	2300000	USD
CY2016	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-16100000	USD
CY2015	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-56200000	USD
CY2017Q4	us-gaap	Disposal Group Including Discontinued Operation Cash DisposalGroupIncludingDiscontinuedOperationCash	0	USD
CY2016Q4	us-gaap	Disposal Group Including Discontinued Operation Cash DisposalGroupIncludingDiscontinuedOperationCash	-5900000	USD
CY2015Q4	us-gaap	Disposal Group Including Discontinued Operation Cash DisposalGroupIncludingDiscontinuedOperationCash	5900000	USD
CY2017	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-35200000	USD
CY2016	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-256300000	USD
CY2015	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-30300000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1032000000.0	USD
CY2015Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1288300000	USD
CY2014Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1318600000	USD
CY2017	us-gaap	Gain Loss On Investments Excluding Other Than Temporary Impairments GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments	31000000.0	USD
CY2016	us-gaap	Gain Loss On Investments Excluding Other Than Temporary Impairments GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments	169100000	USD
CY2015	us-gaap	Gain Loss On Investments Excluding Other Than Temporary Impairments GainLossOnInvestmentsExcludingOtherThanTemporaryImpairments	36800000	USD
CY2017	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	900000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	996800000	USD
CY2016Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1032000000.0	USD
CY2015Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1288300000	USD
CY2017	us-gaap	Income Taxes Paid IncomeTaxesPaid	18800000	USD
CY2016	us-gaap	Income Taxes Paid IncomeTaxesPaid	226100000	USD
CY2015	us-gaap	Income Taxes Paid IncomeTaxesPaid	80100000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	48100000	USD
CY2016	us-gaap	Interest Paid Net InterestPaidNet	56200000	USD
CY2015	us-gaap	Interest Paid Net InterestPaidNet	54800000	USD
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2017	us-gaap	Nature Of Operations NatureOfOperations	Nature of Operations<span style="font-family:inherit;font-size:8pt;"> </span><div style="line-height:120%;padding-bottom:6px;padding-top:6px;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Assurant, Inc. (the “Company”) is a holding company whose subsidiaries globally provide risk management solutions in the housing and lifestyle markets, protecting where consumers live and the goods they buy.</span></div><div style="line-height:120%;padding-bottom:8px;padding-top:8px;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">The Company is traded on the New York Stock Exchange under the symbol "AIZ."</span></div>Through its operating subsidiaries, the Company provides mobile device protection products and services; extended service contracts and related services for consumer electronics and appliances; vehicle protection services; credit insurance; pre-funded funeral insurance and annuity products; lender-placed homeowners insurance; manufactured housing and flood insurance; renters insurance and related products; and field services, valuation services and other property risk management services.
CY2017	us-gaap	Use Of Estimates UseOfEstimates	Use of EstimatesThe preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts. The items affected by the use of estimates include but are not limited to, investments, premiums and accounts receivable, reinsurance recoverables, deferred acquisition costs (“DAC”), deferred income taxes and associated valuation allowances, goodwill, intangible assets, future policy benefits and expenses, unearned premiums, claims and benefits payable, deferred gain on disposal of businesses, pension and post-retirement liabilities and commitments and contingencies. The estimates are sensitive to market conditions, investment yields, mortality, morbidity, commissions and other acquisition expenses, policyholder behavior and other factors. Actual results could differ from the estimates recorded. The Company believes all amounts reported are reasonable and adequate.
CY2017	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	4	reportable_segment
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	4404100000	USD
CY2017	us-gaap	Other Income OtherIncome	1383100000	USD
CY2017	us-gaap	Net Investment Income NetInvestmentIncome	493800000	USD
CY2017	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	30100000	USD
CY2017	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	103900000	USD
CY2017	us-gaap	Revenues Revenues	6415000000.0	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1870600000	USD
CY2017	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1340000000.0	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	2710400000	USD
CY2017	us-gaap	Interest Expense InterestExpense	49500000	USD
CY2017	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	5970500000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	444500000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-75100000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2017Q4	us-gaap	Assets Assets	31843000000.0	USD
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2016	us-gaap	Premiums Earned Net PremiumsEarnedNet	5007300000	USD
CY2016	us-gaap	Other Income OtherIncome	1422500000	USD
CY2016	us-gaap	Net Investment Income NetInvestmentIncome	515700000	USD
CY2016	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	162200000	USD
CY2016	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	394500000	USD
CY2016	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	29600000	USD
CY2016	us-gaap	Revenues Revenues	7531800000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1808500000	USD
CY2016	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1351300000	USD
CY2016	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	3442800000	USD
CY2016	us-gaap	Interest Expense InterestExpense	57600000	USD
CY2016	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-23000000.0	USD
CY2016	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	6683200000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	848600000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	283200000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2016Q4	us-gaap	Assets Assets	29709100000	USD
CY2015	us-gaap	Premiums Earned Net PremiumsEarnedNet	8351000000.0	USD
CY2015	us-gaap	Other Income OtherIncome	1303500000	USD
CY2015	us-gaap	Net Investment Income NetInvestmentIncome	626200000	USD
CY2015	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	31800000	USD
CY2015	aiz	Amortizationof Deferred Gainon Disposalof Businesses AmortizationofDeferredGainonDisposalofBusinesses	13000000.0	USD
CY2015	us-gaap	Revenues Revenues	10325500000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4742500000	USD
CY2015	aiz	Amortization Of Deferred Acquisition Costs And Value Of Business Acquired AmortizationOfDeferredAcquisitionCostsAndValueOfBusinessAcquired	1402600000	USD
CY2015	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	3924100000	USD
CY2015	us-gaap	Interest Expense InterestExpense	55100000	USD
CY2015	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	10124300000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	201200000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59600000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2017	us-gaap	Revenues Revenues	6415000000.0	USD
CY2017Q4	us-gaap	Noncurrent Assets NoncurrentAssets	347600000	USD
CY2016	us-gaap	Revenues Revenues	7531800000	USD
CY2016Q4	us-gaap	Noncurrent Assets NoncurrentAssets	343600000	USD
CY2015	us-gaap	Revenues Revenues	10325500000	USD
CY2015Q4	us-gaap	Noncurrent Assets NoncurrentAssets	298400000	USD
CY2017	us-gaap	Restructuring Charges RestructuringCharges	3300000	USD
CY2016	us-gaap	Restructuring Charges RestructuringCharges	31400000	USD
CY2015	us-gaap	Restructuring Charges RestructuringCharges	85600000	USD
CY2015	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	2568200000	USD
CY2017	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	43500000	USD
CY2016	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	209500000	USD
CY2015	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	65100000	USD
CY2017	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	12200000	USD
CY2016	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	65200000	USD
CY2017Q4	aiz	Maximum Individual State Exposure MaximumIndividualStateExposure	0.004
CY2016Q4	aiz	Maximum Individual State Exposure MaximumIndividualStateExposure	0.005
CY2017Q4	aiz	Advance Refunded Or Escrowed To Maturity Securities AdvanceRefundedOrEscrowedToMaturitySecurities	137700000	USD
CY2016Q4	aiz	Advance Refunded Or Escrowed To Maturity Securities AdvanceRefundedOrEscrowedToMaturitySecurities	215300000	USD
CY2017Q4	aiz	Percentage Of Revenue Securities PercentageOfRevenueSecurities	0.53
CY2016Q4	aiz	Percentage Of Revenue Securities PercentageOfRevenueSecurities	0.46
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	210300000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	213100000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1714200000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1758600000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	1749000000.0	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	1825300000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	3771800000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	4527900000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities Contractual Maturity Total AvailableForSaleSecuritiesDebtMaturitiesContractualMaturityTotal	7445300000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities Contractual Maturity Fair Value Total AvailableForSaleSecuritiesDebtMaturitiesContractualMaturityFairValueTotal	8324900000	USD
CY2017Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	8756500000	USD
CY2017Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	9662600000	USD
CY2017	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	524100000	USD
CY2016	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	533400000	USD
CY2015	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	649500000	USD
CY2017	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	21900000	USD
CY2016	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	17700000	USD
CY2015	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	23300000	USD
CY2017	us-gaap	Net Investment Income NetInvestmentIncome	493800000	USD
CY2016	us-gaap	Net Investment Income NetInvestmentIncome	515700000	USD
CY2015	us-gaap	Net Investment Income NetInvestmentIncome	626200000	USD
CY2017	aiz	Non Income Producing Material Investments NonIncomeProducingMaterialInvestments	0	USD
CY2017	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	3018200000	USD
CY2016	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	4610700000	USD
CY2015	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	31700000	USD
CY2017	aiz	Average Period Of Time These Securities Traded Continuously At Price Below Book Value AveragePeriodOfTimeTheseSecuritiesTradedContinuouslyAtPriceBelowBookValue	P4M
CY2016	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	6900000	USD
CY2015	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNet	5000000.0	USD
CY2017	us-gaap	Gain Loss On Investments GainLossOnInvestments	30100000	USD
CY2016	us-gaap	Gain Loss On Investments GainLossOnInvestments	162200000	USD
CY2015	us-gaap	Gain Loss On Investments GainLossOnInvestments	31800000	USD
CY2017	us-gaap	Impairment Of Investments ImpairmentOfInvestments	900000	USD
CY2016	us-gaap	Impairment Of Investments ImpairmentOfInvestments	6600000	USD
CY2017	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	900000	USD
CY2016	us-gaap	Other Than Temporary Impairment Losses Investments Portion Recognized In Earnings Net Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetAvailableforsaleSecurities	6900000	USD
CY2016	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParentAvailableforsaleSecurities	300000	USD
CY2016Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	24900000	USD
CY2015Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	32400000	USD
CY2014Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	35400000	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	0	USD
CY2016	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	500000	USD
CY2015	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	0	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	0	USD
CY2016	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	0	USD
CY2015	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment	2600000	USD
CY2017	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Cash Flows OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows	2400000	USD
CY2016	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Cash Flows OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows	3600000	USD
CY2015	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Cash Flows OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsCashFlows	2400000	USD
CY2017	aiz	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Matured Paid Down Prepaid Or Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesMaturedPaidDownPrepaidOrSold	4400000	USD
CY2016	aiz	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Matured Paid Down Prepaid Or Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesMaturedPaidDownPrepaidOrSold	4400000	USD
CY2015	aiz	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Matured Paid Down Prepaid Or Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesMaturedPaidDownPrepaidOrSold	3200000	USD
CY2017Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	18100000	USD
CY2016Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	24900000	USD
CY2015Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	32400000	USD
CY2017Q4	aiz	Available For Sale Securities Gross Unrealized Losses Percentage AvailableForSaleSecuritiesGrossUnrealizedLossesPercentage	0.01
CY2016Q4	aiz	Available For Sale Securities Gross Unrealized Losses Percentage AvailableForSaleSecuritiesGrossUnrealizedLossesPercentage	0.02
CY2017Q4	aiz	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Percentage AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesPercentage	0.60
CY2016Q4	aiz	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Aggregate Losses Percentage AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAggregateLossesPercentage	0.89
CY2017Q4	aiz	Number Of Available For Sale Securities Comprising Gross Unrealized Loss NumberOfAvailableForSaleSecuritiesComprisingGrossUnrealizedLoss	686	security
CY2016Q4	aiz	Number Of Available For Sale Securities Comprising Gross Unrealized Loss NumberOfAvailableForSaleSecuritiesComprisingGrossUnrealizedLoss	796	security
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionWithinOneYearAmortizedCost	22200000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionWithinOneYearFairValue	22100000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterOneThroughFiveYearsAmortizedCost	504000000.0	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterOneThroughFiveYearsFairValue	500200000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterFiveThroughTenYearsAmortizedCost	412600000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterFiveThroughTenYearsFairValue	407600000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterTenYearsAmortizedCost	125400000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAfterTenYearsFairValue	123700000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position Single Maturity Date Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionSingleMaturityDateAmortizedCostBasis	1064200000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position Single Maturity Date AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionSingleMaturityDate	1053600000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Maturities In Unrealized Loss Position Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesInUnrealizedLossPositionAmortizedCost	1492500000	USD
CY2017Q4	aiz	Available For Sale Securities Debt Securities In Unrealized Loss Position AvailableForSaleSecuritiesDebtSecuritiesInUnrealizedLossPosition	1473800000	USD
CY2017	aiz	Approximate Percentage Outstanding Principal Balance Of Commercial Mortgage Loans ApproximatePercentageOutstandingPrincipalBalanceOfCommercialMortgageLoans	0.37
CY2017Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	670200000	USD
CY2016Q4	us-gaap	Loans Receivable Commercial Mortgage LoansReceivableCommercialMortgage	626300000	USD
CY2016Q4	aiz	Credit Quality Percentage For Gross Commercial Mortgage Loans CreditQualityPercentageForGrossCommercialMortgageLoans	1.000
CY2016Q4	aiz	Debt Service Coverage Ratios For Commercial Mortgage Loans DebtServiceCoverageRatiosForCommercialMortgageLoans	1.91
CY2016Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	624000000.0	USD
CY2017	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	-1300000	USD
CY2017Q4	aiz	Mortgage Loans Unfunded Commitment MortgageLoansUnfundedCommitment	6100000	USD
CY2017Q4	aiz	Short Term Investments And Fixed Maturities ShortTermInvestmentsAndFixedMaturities	459500000	USD
CY2016Q4	aiz	Short Term Investments And Fixed Maturities ShortTermInvestmentsAndFixedMaturities	437400000	USD
CY2017Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	209200000	USD
CY2017Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	19500000	USD
CY2016Q2	us-gaap	Transfers Of Financial Assets Accounted For As Sale Initial Fair Value Of Assets Obtained As Proceeds TransfersOfFinancialAssetsAccountedForAsSaleInitialFairValueOfAssetsObtainedAsProceeds	259700000	USD
CY2016Q2	us-gaap	Proceeds From Securitizations Of Loans Held For Investment ProceedsFromSecuritizationsOfLoansHeldForInvestment	269800000	USD
CY2016Q2	us-gaap	Gain Loss On Securitization Of Financial Assets GainLossOnSecuritizationOfFinancialAssets	9100000	USD
CY2016Q2	us-gaap	Interests Continued To Be Held By Transferor Fair Value InterestsContinuedToBeHeldByTransferorFairValue	30800000	USD
CY2017Q4	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	12916200000	USD
CY2017Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	1929300000	USD
CY2016Q4	us-gaap	Assets Fair Value Disclosure Recurring AssetsFairValueDisclosureRecurring	12783700000	USD
CY2016Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	1770100000	USD
CY2017Q4	us-gaap	Fair Value Assets Level1 To Level2 Transfers Amount FairValueAssetsLevel1ToLevel2TransfersAmount	0	USD
CY2017	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2017	us-gaap	Premiums Receivable Note PremiumsReceivableNote	Premiums and Accounts Receivable <div style="line-height:120%;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Receivables are reported net of an allowance for uncollectible amounts. A summary of such receivables is as follows:</span></div><div style="line-height:120%;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="8"/></tr><tr><td style="width:73%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;"> </span></div></td><td colspan="7" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">As of December 31,</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2017</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2016</span></div></td></tr><tr><td style="vertical-align:top;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Insurance premiums receivable</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,128.0</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,102.0</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Other receivables</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>121.8</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>145.6</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:top;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Allowance for uncollectible amounts</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(12.5</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(29.6</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:top;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Total</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,237.3</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,218.0</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr></table></div>
CY2017Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	1128000000.0	USD
CY2016Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	1102000000.0	USD
CY2017Q4	us-gaap	Other Receivables OtherReceivables	121800000	USD
CY2016Q4	us-gaap	Other Receivables OtherReceivables	145600000	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	12500000	USD
CY2016Q4	us-gaap	Allowance For Doubtful Accounts Premiums And Other Receivables AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables	29600000	USD
CY2017Q4	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	1237300000	USD
CY2016Q4	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	1218000000.0	USD
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	336300000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	779000000.0	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	126800000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	108200000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	69600000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	74400000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	444500000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	848600000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	201200000	USD
CY2017	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	-111900000	USD
CY2016	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	240100000	USD
CY2015	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	40600000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	41000000.0	USD
CY2016	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	18100000	USD
CY2015	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	22900000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-70900000	USD
CY2016	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	258200000	USD
CY2015	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	63500000	USD
CY2017	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	8700000	USD
CY2016	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	19600000	USD
CY2015	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	200000	USD
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-12900000	USD
CY2016	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	5400000	USD
CY2015	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-4100000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4200000	USD
CY2016	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	25000000.0	USD
CY2015	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-3900000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-75100000	USD
CY2016	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	283200000	USD
CY2015	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	59600000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2016	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2015	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2017	aiz	Effective Income Tax Rate Reconciliation Tax Exempt Interest EffectiveIncomeTaxRateReconciliationTaxExemptInterest	0.023
CY2016	aiz	Effective Income Tax Rate Reconciliation Tax Exempt Interest EffectiveIncomeTaxRateReconciliationTaxExemptInterest	0.013
CY2015	aiz	Effective Income Tax Rate Reconciliation Tax Exempt Interest EffectiveIncomeTaxRateReconciliationTaxExemptInterest	0.068
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Foreign EffectiveIncomeTaxRateReconciliationTaxCreditsForeign	0.023
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Foreign EffectiveIncomeTaxRateReconciliationTaxCreditsForeign	0.019
CY2015	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Foreign EffectiveIncomeTaxRateReconciliationTaxCreditsForeign	0.052
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	0.002
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.001
CY2015	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	0.091
CY2017	aiz	Effective Income Tax Rate Reconciliation Nondeductible Expense Health Insurer Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseHealthInsurerPercent	0
CY2016	aiz	Effective Income Tax Rate Reconciliation Nondeductible Expense Health Insurer Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseHealthInsurerPercent	0.018
CY2015	aiz	Effective Income Tax Rate Reconciliation Nondeductible Expense Health Insurer Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseHealthInsurerPercent	0.069
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.064
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	0
CY2015	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	0
CY2017	aiz	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent	-0.398
CY2016	aiz	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent	0
CY2015	aiz	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent	0
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0
CY2015	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	-0.080
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.013
CY2016	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.001
CY2015	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.014
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.169
CY2016	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.334
CY2015	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.296
CY2017	aiz	Effective Income Tax Rate Reconciliation Tax Benefit Foreign Reorganization EffectiveIncomeTaxRateReconciliationTaxBenefitForeignReorganization	0.014
CY2016	aiz	Effective Income Tax Rate Reconciliation Tax Benefit Foreign Reorganization EffectiveIncomeTaxRateReconciliationTaxBenefitForeignReorganization	0.022
CY2015	aiz	Effective Income Tax Rate Reconciliation Tax Benefit Foreign Reorganization EffectiveIncomeTaxRateReconciliationTaxBenefitForeignReorganization	0.065
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2017	aiz	Effective Income Tax Rate Reconciliation Tax Cutsand Jobs Actof2017 Percent EffectiveIncomeTaxRateReconciliationTaxCutsandJobsActof2017Percent	-0.398
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	34200000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	37000000.0	USD
CY2014Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	6300000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1000000.0	USD
CY2016	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	1000000.0	USD
CY2015	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	30700000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2016	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2015	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromCurrentPeriodTaxPositions	100000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	300000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1400000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	2100000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	28200000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3800000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	400000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	600000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	1400000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	1600000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	6700000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	34200000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	37000000.0	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	6800000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	34500000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	35600000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	100000	USD
CY2016	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	600000	USD
CY2015	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	200000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	200000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	200000	USD
CY2015Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1700000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	0	USD
CY2017Q4	aiz	Deferred Tax Assets Policyholder And Separate Account Reserves DeferredTaxAssetsPolicyholderAndSeparateAccountReserves	359100000	USD
CY2016Q4	aiz	Deferred Tax Assets Policyholder And Separate Account Reserves DeferredTaxAssetsPolicyholderAndSeparateAccountReserves	571700000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	4600000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Accrued Liabilities DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities	39300000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	70800000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	102600000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	42300000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	31700000	USD
CY2017Q4	aiz	Deferred Tax Assets Deferred Gain On Sale Of Business DeferredTaxAssetsDeferredGainOnSaleOfBusiness	26900000	USD
CY2016Q4	aiz	Deferred Tax Assets Deferred Gain On Sale Of Business DeferredTaxAssetsDeferredGainOnSaleOfBusiness	81300000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	27200000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	37800000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	35800000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Postretirement Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsPostretirementBenefits	58500000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	30000000.0	USD
CY2016Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Other DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsOther	48400000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	39300000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	78600000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	636000000.0	USD
CY2016Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	1049900000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	9200000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	12600000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	626800000	USD
CY2016Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	1037300000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	674500000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Deferred Policy Acquisition Cost DeferredTaxLiabilitiesDeferredExpenseDeferredPolicyAcquisitionCost	984300000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	201100000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	243800000	USD
CY2017Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	875600000	USD
CY2016Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	1228100000	USD
CY2017Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	248800000	USD
CY2016Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	190800000	USD
CY2017Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	9200000	USD
CY2017Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	177800000	USD
CY2017Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	177800000	USD
CY2017	us-gaap	Deferred Policy Acquisition Costs Text Block1 DeferredPolicyAcquisitionCostsTextBlock1	Deferred Acquisition Costs<span style="font-family:inherit;font-size:8pt;"> </span><div style="line-height:120%;text-indent:32px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Information about deferred acquisition costs is as follows:</span></div><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="12"/></tr><tr><td style="width:59%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;"> </span></div></td><td colspan="11" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">December 31,</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2017</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2016</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2015</span></div></td></tr><tr><td style="vertical-align:top;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Beginning balance</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,267.4</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,150.9</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,957.7</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:top;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Costs deferred</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,549.2</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,458.7</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,587.5</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:top;background-color:#cceeff;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Amortization</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(1,332.1</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(1,342.2</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(1,394.3</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:top;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Ending balance</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,484.5</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,267.4</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,150.9</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr></table></div>
CY2016Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	3267400000	USD
CY2015Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	3150900000	USD
CY2014Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	2957700000	USD
CY2017	us-gaap	Deferred Policy Acquisition Costs Additions DeferredPolicyAcquisitionCostsAdditions	1549200000	USD
CY2016	us-gaap	Deferred Policy Acquisition Costs Additions DeferredPolicyAcquisitionCostsAdditions	1458700000	USD
CY2015	us-gaap	Deferred Policy Acquisition Costs Additions DeferredPolicyAcquisitionCostsAdditions	1587500000	USD
CY2017	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1332100000	USD
CY2016	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1342200000	USD
CY2015	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1394300000	USD
CY2017Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	3484500000	USD
CY2016Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	3267400000	USD
CY2015Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	3150900000	USD
CY2017Q4	us-gaap	Land Land	13700000	USD
CY2016Q4	us-gaap	Land Land	14900000	USD
CY2017Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	248000000.0	USD
CY2016Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	269300000	USD
CY2017Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	434500000	USD
CY2016Q4	us-gaap	Furniture And Fixtures Gross FurnitureAndFixturesGross	393700000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	696200000	USD
CY2016Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	677900000	USD
CY2017Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	348600000	USD
CY2016Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	334300000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	347600000	USD
CY2016Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	343600000	USD
CY2017	us-gaap	Gain Loss On Disposition Of Assets GainLossOnDispositionOfAssets	5700000	USD
CY2017	us-gaap	Depreciation Depreciation	34200000	USD
CY2016	us-gaap	Depreciation Depreciation	41700000	USD
CY2015	us-gaap	Depreciation Depreciation	47400000	USD
CY2015Q4	us-gaap	Goodwill Goodwill	833500000	USD
CY2016	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	20500000	USD
CY2016	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-23100000	USD
CY2016	us-gaap	Goodwill Other Increase Decrease GoodwillOtherIncreaseDecrease	0	USD
CY2016Q4	us-gaap	Goodwill Goodwill	830900000	USD
CY2017	us-gaap	Goodwill Acquired During Period GoodwillAcquiredDuringPeriod	70000000.0	USD
CY2017	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	16800000	USD
CY2017Q4	us-gaap	Goodwill Goodwill	917700000	USD
CY2017Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	1260000000	USD
CY2016Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	32100000	USD
CY2015Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	41200000	USD
CY2014Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	45500000	USD
CY2017	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	0	USD
CY2016	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	0	USD
CY2015	us-gaap	Present Value Of Future Insurance Profits Additions From Acquisitions PresentValueOfFutureInsuranceProfitsAdditionsFromAcquisitions	4100000	USD
CY2017	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	7900000	USD
CY2016	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	9200000	USD
CY2015	us-gaap	Present Value Of Future Insurance Profits Amortization Expense1 PresentValueOfFutureInsuranceProfitsAmortizationExpense1	8300000	USD
CY2017	aiz	Value Of Business Acquired Vob Translation Adjustment And Other ValueOfBusinessAcquiredVOBTranslationAdjustmentAndOther	200000	USD
CY2016	aiz	Value Of Business Acquired Vob Translation Adjustment And Other ValueOfBusinessAcquiredVOBTranslationAdjustmentAndOther	100000	USD
CY2015	aiz	Value Of Business Acquired Vob Translation Adjustment And Other ValueOfBusinessAcquiredVOBTranslationAdjustmentAndOther	-100000	USD
CY2017Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	24400000	USD
CY2016Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	32100000	USD
CY2015Q4	us-gaap	Value Of Business Acquired Voba ValueOfBusinessAcquiredVOBA	41200000	USD
CY2017Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	595400000	USD
CY2017Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	306800000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	288600000	USD
CY2016Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	538400000	USD
CY2016Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	298100000	USD
CY2016Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	240300000	USD
CY2017Q4	us-gaap	Indefinite Lived Intangible Assets Excluding Goodwill IndefiniteLivedIntangibleAssetsExcludingGoodwill	2100000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	72600000	USD
CY2016	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	67700000	USD
CY2015	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	71700000	USD
CY2017	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="12"/></tr><tr><td style="width:59%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:1%;"/><td style="width:11%;"/><td style="width:1%;"/></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="11" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">Years Ended December 31,</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2017</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2016</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;font-weight:bold;">2015</span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Claims and benefits payable, at beginning of year</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,301.2</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,896.7</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,698.6</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Less: Reinsurance ceded and other</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(2,718.2</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(1,496.5</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(1,254.4</span></span></div></td><td style="vertical-align:bottom;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Net claims and benefits payable, at beginning of year</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>583.0</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,400.2</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,444.2</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Incurred losses and loss adjustment expenses related to:</span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Current year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,965.0</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,028.9</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>4,973.4</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Prior year's interest</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>—</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>9.8</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>59.8</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Prior years</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(58.5</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(196.2</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>(150.9</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-right:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">)</span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Total incurred losses and loss adjustment expenses</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,906.5</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,842.5</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>4,882.3</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Paid losses and loss adjustment expenses related to:</span></div></td><td colspan="3" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="3" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Current year</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,536.4</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,595.7</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,846.0</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:28px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Prior years</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>364.2</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,064.0</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,080.3</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Total paid losses and loss adjustment expenses</span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,900.6</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,659.7</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;border-bottom:1px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>4,926.3</span></span></div></td><td style="vertical-align:bottom;border-bottom:1px solid #000000;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Net claims and benefits payable, at end of year</span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>588.9</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>583.0</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,400.2</span></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Plus: Reinsurance ceded and other (1)</span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,193.3</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>2,718.2</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>1,496.5</span></span></div></td><td style="vertical-align:bottom;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr><tr><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Claims and benefits payable, at end of year (1)</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,782.2</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,301.2</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td><td style="vertical-align:bottom;background-color:#cceeff;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"> </span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">$</span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;padding-top:2px;padding-bottom:2px;border-top:1px solid #000000;"><div style="text-align:right;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><span>3,896.7</span></span></div></td><td style="vertical-align:bottom;border-bottom:3px double #000000;background-color:#cceeff;border-top:1px solid #000000;"><div style="text-align:left;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div></td></tr></table></div><span style="font-family:inherit;font-size:10pt;"><br/></span><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:24px;"/><td/></tr><tr><td style="vertical-align:top"><div style="line-height:120%;font-size:8pt;padding-left:0px;"><span style="font-family:inherit;font-size:8pt;">(1)</span></div></td><td style="vertical-align:top;"><div style="line-height:120%;text-align:left;font-size:8pt;"><span style="font-family:inherit;font-size:8pt;">Includes reinsurance recoverables and claims and benefits payable of </span><span style="font-family:inherit;font-size:8pt;"><span>$555.0 million</span></span><span style="font-family:inherit;font-size:8pt;">, </span><span style="font-family:inherit;font-size:8pt;"><span>$153.3 million</span></span><span style="font-family:inherit;font-size:8pt;"> and </span><span style="font-family:inherit;font-size:8pt;"><span>$64.0 million</span></span><span style="font-family:inherit;font-size:8pt;"> as of December 31, 2017, 2016 and 2015 which was ceded to the U.S. government. Assurant acts as an administrator for the U.S. government under the voluntary National Flood Insurance Program.</span></div></td></tr></table><br/>
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3301200000	USD
CY2015Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3896700000	USD
CY2014Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3698600000	USD
CY2016Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	2718200000	USD
CY2015Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	1496500000	USD
CY2014Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	1254400000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	583000000.0	USD
CY2015Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2400200000	USD
CY2014Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2444200000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	1965000000.0	USD
CY2016	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	2028900000	USD
CY2015	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	4973400000	USD
CY2017	aiz	Prior Year Claimsand Claims Adjustment Expense Interest PriorYearClaimsandClaimsAdjustmentExpenseInterest	0	USD
CY2016	aiz	Prior Year Claimsand Claims Adjustment Expense Interest PriorYearClaimsandClaimsAdjustmentExpenseInterest	9800000	USD
CY2015	aiz	Prior Year Claimsand Claims Adjustment Expense Interest PriorYearClaimsandClaimsAdjustmentExpenseInterest	59800000	USD
CY2017	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-58500000	USD
CY2016	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-196200000	USD
CY2015	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-150900000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1906500000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1842500000	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	4882300000	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1536400000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1595700000	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	3846000000.0	USD
CY2017	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	364200000	USD
CY2016	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	2064000000.0	USD
CY2015	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	1080300000	USD
CY2017	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	1900600000	USD
CY2016	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	3659700000	USD
CY2015	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	4926300000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	588900000	USD
CY2016Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	583000000.0	USD
CY2015Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2400200000	USD
CY2017Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	3193300000	USD
CY2016Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	2718200000	USD
CY2015Q4	aiz	Reinsurance Cededand Othercasereservesand Ibnr ReinsuranceCededandOthercasereservesandIBNR	1496500000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3782200000	USD
CY2016Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3301200000	USD
CY2015Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3896700000	USD
CY2017Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	557400000	USD
CY2017Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	1803900000	USD
CY2017Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claims Adjustment Expense Accumulated Unallocated Claim Adjustment Expense ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense	9200000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	3782200000	USD
CY2017Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	9790200000	USD
CY2016Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	9083200000	USD
CY2017Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	9790500000	USD
CY2017Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	300000	USD
CY2017Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	9790200000	USD
CY2017Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	300000	USD
CY2017	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	0	USD
CY2017	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9530800000	USD
CY2016	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9674800000	USD
CY2015	us-gaap	Direct Premiums Earned DirectPremiumsEarned	11600700000	USD
CY2017	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	153900000	USD
CY2016	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	369900000	USD
CY2015	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	526000000.0	USD
CY2017	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5280600000	USD
CY2016	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5037400000	USD
CY2015	us-gaap	Ceded Premiums Earned CededPremiumsEarned	3775700000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	4404100000	USD
CY2016	us-gaap	Premiums Earned Net PremiumsEarnedNet	5007300000	USD
CY2015	us-gaap	Premiums Earned Net PremiumsEarnedNet	8351000000.0	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	6439500000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	5721200000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	6962300000	USD
CY2017	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	228100000	USD
CY2016	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	169300000	USD
CY2015	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	310900000	USD
CY2017	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	4797000000.0	USD
CY2016	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	4082000000.0	USD
CY2015	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2530700000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1870600000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1808500000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4742500000	USD
CY2017Q4	us-gaap	Assets Held By Insurance Regulators AssetsHeldByInsuranceRegulators	596500000	USD
CY2016Q4	us-gaap	Assets Held By Insurance Regulators AssetsHeldByInsuranceRegulators	635400000	USD
CY2016Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	55941480	shares
CY2015Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	65850386	shares
CY2014Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	69299559	shares
CY2017	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	85314	shares
CY2016	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	104751	shares
CY2015	us-gaap	Stock Issued During Period Shares Employee Stock Purchase Plans StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans	130622	shares
CY2017	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	3933209	shares
CY2016	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	10518552	shares
CY2015	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	4184889	shares
CY2017Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	52417812	shares
CY2016Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	55941480	shares
CY2015Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	65850386	shares
CY2017Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	800000000	shares
CY2017	aiz	Forfeiture Rate ForfeitureRate	0.05
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Plan Modification Incremental Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost	900000	USD
CY2016	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Plan Modification Incremental Compensation Cost ShareBasedCompensationArrangementByShareBasedPaymentAwardPlanModificationIncrementalCompensationCost	-2700000	USD
CY2015	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	284700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	156000000.0	USD
CY2017	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	16600000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	139400000	USD
CY2017	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	3933209	shares
CY2017	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	389500000	USD
CY2017Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	293400000	USD
CY2016	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	10518552	shares
CY2015	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	4184889	shares
CY2016	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	869400000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	94800000	USD
CY2016	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	118800000	USD
CY2016	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-24000000.0	USD
CY2015	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-422000000.0	USD
CY2015	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	15200000	USD
CY2015	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-437200000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-16600000	USD
CY2016	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-118800000	USD
CY2015	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-15200000	USD
CY2017	us-gaap	Statutory Accounting Practices Statutory Net Income Amount StatutoryAccountingPracticesStatutoryNetIncomeAmount	481800000	USD
CY2016	us-gaap	Statutory Accounting Practices Statutory Net Income Amount StatutoryAccountingPracticesStatutoryNetIncomeAmount	888700000	USD
CY2015	us-gaap	Statutory Accounting Practices Statutory Net Income Amount StatutoryAccountingPracticesStatutoryNetIncomeAmount	170900000	USD
CY2017Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Balance StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance	1558200000	USD
CY2016Q4	us-gaap	Statutory Accounting Practices Statutory Capital And Surplus Balance StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance	1684500000	USD
CY2017	us-gaap	Business Exit Costs1 BusinessExitCosts1	106400000	USD
CY2017Q4	aiz	Statutory Accounting Practices Statutory Surplus Reduction Due To Tcja StatutoryAccountingPracticesStatutorySurplusReductionDueToTCJA	95000000.0	USD
CY2017	aiz	Statutory Accounting Practices Statutory Surplus Percentage StatutoryAccountingPracticesStatutorySurplusPercentage	0.10
CY2017Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	300000000.0	USD
CY2017	aiz	Statutory Accounting Practices Risk Based Capital Requirements Authorized Control Level StatutoryAccountingPracticesRiskBasedCapitalRequirementsAuthorizedControlLevel	1
CY2017	aiz	Percentage Of Pension Plan Deficit Added To Amount Of Service Cost PercentageOfPensionPlanDeficitAddedToAmountOfServiceCost	0.15
CY2017	us-gaap	Pension Contributions PensionContributions	0	USD
CY2016Q1	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	29600000	USD
CY2016	us-gaap	Earnings Per Share Basic Distributed EarningsPerShareBasicDistributed	2.05
CY2015	us-gaap	Earnings Per Share Basic Distributed EarningsPerShareBasicDistributed	1.38
CY2017	aiz	Numberofbondsinyieldcurvethatisutilizedinthecashflowanalysisforthepensionplan Numberofbondsinyieldcurvethatisutilizedinthecashflowanalysisforthepensionplan	259	security
CY2017	aiz	Defined Benefit Plan Actual Return On Plan Assets Percentage DefinedBenefitPlanActualReturnOnPlanAssetsPercentage	0.111
CY2016	aiz	Defined Benefit Plan Actual Return On Plan Assets Percentage DefinedBenefitPlanActualReturnOnPlanAssetsPercentage	0.081
CY2015	aiz	Defined Benefit Plan Actual Return On Plan Assets Percentage DefinedBenefitPlanActualReturnOnPlanAssetsPercentage	-0.006
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	37000000.0	USD
CY2016	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	60900000	USD
CY2015	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	44500000	USD
CY2017	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.03
CY2016Q4	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	22500000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	519600000	USD
CY2016	us-gaap	Net Income Loss NetIncomeLoss	565400000	USD
CY2015	us-gaap	Net Income Loss NetIncomeLoss	141600000	USD
CY2017	us-gaap	Dividends Cash DividendsCash	119000000.0	USD
CY2016	us-gaap	Dividends Cash DividendsCash	125400000	USD
CY2015	us-gaap	Dividends Cash DividendsCash	94200000	USD
CY2017	us-gaap	Undistributed Earnings UndistributedEarnings	400600000	USD
CY2016	us-gaap	Undistributed Earnings UndistributedEarnings	440000000.0	USD
CY2015	us-gaap	Undistributed Earnings UndistributedEarnings	47400000	USD
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54986654	shares
CY2016	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	61261288	shares
CY2015	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	68163825	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55311032	shares
CY2016	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	61934774	shares
CY2015	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	69017209	shares
CY2017	us-gaap	Earnings Per Share Basic Distributed EarningsPerShareBasicDistributed	2.16
CY2017	us-gaap	Earnings Per Share Basic Undistributed EarningsPerShareBasicUndistributed	7.29
CY2016	us-gaap	Earnings Per Share Basic Undistributed EarningsPerShareBasicUndistributed	7.18
CY2015	us-gaap	Earnings Per Share Basic Undistributed EarningsPerShareBasicUndistributed	0.70
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.45
CY2016	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	9.23
CY2015	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.08
CY2017	us-gaap	Earnings Per Share Diluted Distributed EarningsPerShareDilutedDistributed	2.15
CY2016	us-gaap	Earnings Per Share Diluted Distributed EarningsPerShareDilutedDistributed	2.03
CY2015	us-gaap	Earnings Per Share Diluted Distributed EarningsPerShareDilutedDistributed	1.36
CY2017	us-gaap	Earnings Per Share Diluted Undistributed EarningsPerShareDilutedUndistributed	7.24
CY2016	us-gaap	Earnings Per Share Diluted Undistributed EarningsPerShareDilutedUndistributed	7.10
CY2015	us-gaap	Earnings Per Share Diluted Undistributed EarningsPerShareDilutedUndistributed	0.69
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.39
CY2016	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	9.13
CY2015	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.05
CY2017Q1	us-gaap	Revenues Revenues	1551500000	USD
CY2017Q2	us-gaap	Revenues Revenues	1600500000	USD
CY2017Q3	us-gaap	Revenues Revenues	1586400000	USD
CY2017Q4	us-gaap	Revenues Revenues	1676600000	USD
CY2017Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	215100000	USD
CY2017Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	178700000	USD
CY2017Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-107600000	USD
CY2017Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	158300000	USD
CY2017Q1	us-gaap	Net Income Loss NetIncomeLoss	143800000	USD
CY2017Q2	us-gaap	Net Income Loss NetIncomeLoss	120200000	USD
CY2017Q3	us-gaap	Net Income Loss NetIncomeLoss	-57300000	USD
CY2017Q4	us-gaap	Net Income Loss NetIncomeLoss	312900000	USD
CY2017Q1	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	3.83
CY2017Q2	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	3.24
CY2017Q3	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	-1.97
CY2017Q4	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	2.93
CY2017Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.56
CY2017Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.18
CY2017Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.05
CY2017Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.79
CY2017Q1	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	3.79
CY2017Q2	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	3.22
CY2017Q3	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	-1.97
CY2017Q4	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	2.91
CY2017Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.53
CY2017Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.16
CY2017Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.05
CY2017Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.76
CY2016Q1	us-gaap	Revenues Revenues	2147500000	USD
CY2016Q2	us-gaap	Revenues Revenues	1797800000	USD
CY2016Q3	us-gaap	Revenues Revenues	1834100000	USD
CY2016Q4	us-gaap	Revenues Revenues	1752400000	USD
CY2016Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	337600000	USD
CY2016Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	235500000	USD
CY2016Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	220900000	USD
CY2016Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	54600000	USD
CY2016Q1	us-gaap	Net Income Loss NetIncomeLoss	220400000	USD
CY2016Q2	us-gaap	Net Income Loss NetIncomeLoss	169300000	USD
CY2016Q3	us-gaap	Net Income Loss NetIncomeLoss	144400000	USD
CY2016Q4	us-gaap	Net Income Loss NetIncomeLoss	31300000	USD
CY2016Q1	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	5.19
CY2016Q2	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	3.78
CY2016Q3	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	3.66
CY2016Q4	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Basic IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareBasic	0.95
CY2016Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2016Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.72
CY2016Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.40
CY2016Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.54
CY2016Q1	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	5.12
CY2016Q2	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	3.75
CY2016Q3	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	3.63
CY2016Q4	aiz	Income Loss From Continuing Operations Before Provision For Income Taxes Per Share Diluted IncomeLossFromContinuingOperationsBeforeProvisionForIncomeTaxesPerShareDiluted	0.94
CY2016Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.34
CY2016Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.70
CY2016Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.37
CY2016Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.54
CY2017Q4	aiz	Tax Cutsand Jobs Actof2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsandJobsActof2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-177000000.0	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	21600000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	16400000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	13100000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	9800000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	5200000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	3100000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	69200000	USD
CY2017Q4	us-gaap	Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals	800000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	23800000	USD
CY2016	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	26500000	USD
CY2015	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	31800000	USD
CY2017	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	5900000	USD
CY2016	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	5600000	USD
CY2015	us-gaap	Operating Leases Rent Expense Sublease Rentals1 OperatingLeasesRentExpenseSubleaseRentals1	2400000	USD
CY2017Q4	us-gaap	Purchase Obligation PurchaseObligation	13500000	USD
CY2017Q4	us-gaap	Purchase Obligation Due In Next Twelve Months PurchaseObligationDueInNextTwelveMonths	4500000	USD
CY2017Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	18100000	USD
CY2016Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	17200000	USD
CY2017Q2	aiz	Paymentsof Examination Complianceand Monitoring Costs PaymentsofExaminationComplianceandMonitoringCosts	85000000.0	USD
CY2016	aiz	Guaranty Expense GuarantyExpense	12500000	USD
CY2017	aiz	Guaranty Expense GuarantyExpense	3000000.0	USD
CY2017Q4	us-gaap	Guaranty Liabilities GuarantyLiabilities	6500000	USD
CY2017Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	10595700000	USD
CY2017Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Fair Value SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue	11562500000	USD
CY2017Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Carrying Amount SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCarryingAmount	11553500000	USD
CY2015Q4	us-gaap	Supplementary Insurance Information Liability For Future Policy Benefits Losses Claims And Loss Expense Reserves SupplementaryInsuranceInformationLiabilityForFuturePolicyBenefitsLossesClaimsAndLossExpenseReserves	9466700000	USD
CY2015Q4	us-gaap	Supplementary Insurance Information Unearned Premiums SupplementaryInsuranceInformationUnearnedPremiums	6423700000	USD
CY2015Q4	us-gaap	Supplementary Insurance Information Other Policy Claims And Benefits Payable SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable	3896700000	USD
CY2015	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	8351000000.0	USD
CY2017Q4	us-gaap	Supplementary Insurance Information Deferred Policy Acquisition Costs SupplementaryInsuranceInformationDeferredPolicyAcquisitionCosts	3484500000	USD
CY2017Q4	us-gaap	Supplementary Insurance Information Liability For Future Policy Benefits Losses Claims And Loss Expense Reserves SupplementaryInsuranceInformationLiabilityForFuturePolicyBenefitsLossesClaimsAndLossExpenseReserves	10397400000	USD
CY2017Q4	us-gaap	Supplementary Insurance Information Unearned Premiums SupplementaryInsuranceInformationUnearnedPremiums	7038600000	USD
CY2017Q4	us-gaap	Supplementary Insurance Information Other Policy Claims And Benefits Payable SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable	3782200000	USD
CY2017	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	4404100000	USD
CY2017	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	493800000	USD
CY2017	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	1870600000	USD
CY2017	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	1332100000	USD
CY2017	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	2718300000	USD
CY2017	us-gaap	Supplementary Insurance Information Premiums Written SupplementaryInsuranceInformationPremiumsWritten	2357000000.0	USD
CY2016Q4	us-gaap	Supplementary Insurance Information Deferred Policy Acquisition Costs SupplementaryInsuranceInformationDeferredPolicyAcquisitionCosts	3267400000	USD
CY2016Q4	us-gaap	Supplementary Insurance Information Liability For Future Policy Benefits Losses Claims And Loss Expense Reserves SupplementaryInsuranceInformationLiabilityForFuturePolicyBenefitsLossesClaimsAndLossExpenseReserves	10112900000	USD
CY2016Q4	us-gaap	Supplementary Insurance Information Unearned Premiums SupplementaryInsuranceInformationUnearnedPremiums	6626500000	USD
CY2016Q4	us-gaap	Supplementary Insurance Information Other Policy Claims And Benefits Payable SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable	3301200000	USD
CY2016	us-gaap	Supplementary Insurance Information Premium Revenue SupplementaryInsuranceInformationPremiumRevenue	5007300000	USD
CY2016	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	515700000	USD
CY2016	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	1808500000	USD
CY2016	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	1342200000	USD
CY2016	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	3451900000	USD
CY2016	us-gaap	Supplementary Insurance Information Premiums Written SupplementaryInsuranceInformationPremiumsWritten	2321200000	USD
CY2015Q4	us-gaap	Supplementary Insurance Information Deferred Policy Acquisition Costs SupplementaryInsuranceInformationDeferredPolicyAcquisitionCosts	3150900000	USD
CY2015	us-gaap	Supplementary Insurance Information Net Investment Income SupplementaryInsuranceInformationNetInvestmentIncome	626200000	USD
CY2015	us-gaap	Supplementary Insurance Information Benefits Claims Losses And Settlement Expense SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense	4742500000	USD
CY2015	us-gaap	Supplementary Insurance Information Amortization Of Deferred Policy Acquisition Costs SupplementaryInsuranceInformationAmortizationOfDeferredPolicyAcquisitionCosts	1394300000	USD
CY2015	us-gaap	Supplementary Insurance Information Other Operating Expense SupplementaryInsuranceInformationOtherOperatingExpense	3932400000	USD
CY2015	us-gaap	Supplementary Insurance Information Premiums Written SupplementaryInsuranceInformationPremiumsWritten	2422000000.0	USD
CY2017Q4	us-gaap	Life Insurance In Force Gross LifeInsuranceInForceGross	77852800000	USD
CY2017Q4	us-gaap	Life Insurance In Force Ceded LifeInsuranceInForceCeded	74851800000	USD
CY2017Q4	us-gaap	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	614800000	USD
CY2017Q4	us-gaap	Life Insurance In Force Net LifeInsuranceInForceNet	3615800000	USD
CY2017Q4	us-gaap	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.170
CY2017	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9530800000	USD
CY2017	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5280600000	USD
CY2017	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	153900000	USD
CY2017	us-gaap	Premiums Earned Net PremiumsEarnedNet	4404100000	USD
CY2017	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.035
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	6439500000	USD
CY2017	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	4797000000.0	USD
CY2017	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	228100000	USD
CY2017	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1870600000	USD
CY2017	aiz	Benefits Percentage Of Amount Assumed To Net BenefitsPercentageOfAmountAssumedToNet	0.122
CY2016Q4	us-gaap	Life Insurance In Force Gross LifeInsuranceInForceGross	87831800000	USD
CY2016Q4	us-gaap	Life Insurance In Force Ceded LifeInsuranceInForceCeded	84880200000	USD
CY2016Q4	us-gaap	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	1369300000	USD
CY2016Q4	us-gaap	Life Insurance In Force Net LifeInsuranceInForceNet	4320900000	USD
CY2016Q4	us-gaap	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.317
CY2016	us-gaap	Direct Premiums Earned DirectPremiumsEarned	9674800000	USD
CY2016	us-gaap	Ceded Premiums Earned CededPremiumsEarned	5037400000	USD
CY2016	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	369900000	USD
CY2016	us-gaap	Premiums Earned Net PremiumsEarnedNet	5007300000	USD
CY2016	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.074
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	5721200000	USD
CY2016	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	4082000000.0	USD
CY2016	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	169300000	USD
CY2016	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1808500000	USD
CY2016	aiz	Benefits Percentage Of Amount Assumed To Net BenefitsPercentageOfAmountAssumedToNet	0.094
CY2015Q4	us-gaap	Life Insurance In Force Gross LifeInsuranceInForceGross	93926100000	USD
CY2015Q4	us-gaap	Life Insurance In Force Ceded LifeInsuranceInForceCeded	26786300000	USD
CY2015Q4	us-gaap	Life Insurance In Force Assumed LifeInsuranceInForceAssumed	1397200000	USD
CY2015Q4	us-gaap	Life Insurance In Force Net LifeInsuranceInForceNet	68537000000.0	USD
CY2015Q4	us-gaap	Life Insurance In Force Percentage Assumed To Net LifeInsuranceInForcePercentageAssumedToNet	0.020
CY2015	us-gaap	Direct Premiums Earned DirectPremiumsEarned	11600700000	USD
CY2015	us-gaap	Ceded Premiums Earned CededPremiumsEarned	3775700000	USD
CY2015	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	526000000.0	USD
CY2015	us-gaap	Premiums Earned Net PremiumsEarnedNet	8351000000.0	USD
CY2015	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.063
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	6962300000	USD
CY2015	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2530700000	USD
CY2015	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	310900000	USD
CY2015	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4742500000	USD
CY2015	aiz	Benefits Percentage Of Amount Assumed To Net BenefitsPercentageOfAmountAssumedToNet	0.066
CY2016Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	44800000	USD
CY2017	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	-13100000	USD
CY2017	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	200000	USD
CY2017	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	8800000	USD
CY2017Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	23100000	USD
CY2015Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	54300000	USD
CY2016	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	-6800000	USD
CY2016	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	-100000	USD
CY2016	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	2600000	USD
CY2016Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	44800000	USD
CY2014Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	64000000.0	USD
CY2015	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	600000	USD
CY2015	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	-1200000	USD
CY2015	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	9100000	USD
CY2015Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	54300000	USD

Files In Submission

Name	View Source	Status
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0001628280-18-001695-index.html	Edgar Link	pending
0001628280-18-001695.txt	Edgar Link	pending
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$AIZ
ASSURANT, INC. Stock $aiz

2017 Form 10-K Financial Statement

#000162828018001695 Filed on February 14, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AIZ ASSURANT, INC. Stock $aiz

2017 Form 10-K Financial Statement

#000162828018001695 Filed on February 14, 2018

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AIZ
ASSURANT, INC. Stock $aiz