$ARGD
Argo Group International Holdings, Inc. Stock $argd

$argd Overview Financials Valuation SEC Filings Company Website

2020 Q2 Form 10-Q Financial Statement

#000162828020011889 Filed on August 06, 2020

Income Statement

Concept	2020 Q2	2019 Q2
Revenue	$452.7M	$488.6M
YoY Change	-7.35%	5.46%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$9.100M	$7.100M
YoY Change	28.17%	-7.79%
% of Gross Profit
Operating Expenses	$438.1M	$455.0M
YoY Change	-3.71%	12.65%
Operating Profit
YoY Change
Interest Expense	$7.000M	$9.400M
YoY Change	-25.53%	20.51%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$5.900M	$27.80M
YoY Change	-78.78%	-51.31%
Income Tax	$11.30M	$800.0K
% Of Pretax Income	191.53%	2.88%
Net Earnings	-$5.400M	$27.00M
YoY Change	-120.0%	-35.41%
Net Earnings / Revenue	-1.19%	5.53%
Basic Earnings Per Share	-$0.16	$0.79
Diluted Earnings Per Share	-$0.16	$0.78
COMMON SHARES
Basic Shares Outstanding	34.63M shares	34.20M shares
Diluted Shares Outstanding	34.63M shares	34.78M shares

Balance Sheet

Concept	2020 Q2	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$187.7M	$182.3M
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	$87.00M	$113.0M
YoY Change	-23.01%
Goodwill	$156.5M	$177.0M
YoY Change	-11.58%	9.67%
Intangibles	$91.10M	$92.60M
YoY Change	-1.62%	-17.25%
Long-Term Investments	$4.852B	$4.878B
YoY Change	-0.53%	2.29%
Other Assets	$32.00M
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$10.38B	$10.15B
YoY Change	2.22%	11.51%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$254.0M	$405.0M
YoY Change	-37.28%	249.14%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$281.0M	$405.0M
YoY Change	-30.62%	211.54%
LONG-TERM LIABILITIES
Long-Term Debt	$579.0M	$579.0M
YoY Change	0.0%	-0.34%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$579.0M	$579.0M
YoY Change	0.0%	-25.86%
TOTAL LIABILITIES
Total Short-Term Liabilities	$281.0M	$405.0M
Total Long-Term Liabilities	$579.0M	$579.0M
Total Liabilities	$8.671B	$8.242B
YoY Change	5.21%	12.76%
SHAREHOLDERS EQUITY
Retained Earnings	$734.4M	$942.8M
YoY Change	-22.1%	6.6%
Common Stock	$1.423B	$1.415B
YoY Change	0.51%	0.35%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$455.1M	$455.1M
YoY Change	0.0%	2.55%
Treasury Stock Shares	11.32M shares	11.32M shares
Shareholders Equity	$1.708B	$1.912B
YoY Change
Total Liabilities & Shareholders Equity	$10.38B	$10.15B
YoY Change	2.22%	11.51%

Cashflow Statement

Concept	2020 Q2	2019 Q2
OPERATING ACTIVITIES
Net Income	-$5.400M	$27.00M
YoY Change	-120.0%	-35.41%
Depreciation, Depletion And Amortization	$9.100M	$7.100M
YoY Change	28.17%	-7.79%
Cash From Operating Activities	-$71.70M	-$60.50M
YoY Change	18.51%	118.41%
INVESTING ACTIVITIES
Capital Expenditures	-$5.300M	-$8.400M
YoY Change	-36.9%	82.61%
Acquisitions
YoY Change
Other Investing Activities	$119.8M	$110.4M
YoY Change	8.51%	-2448.94%
Cash From Investing Activities	$114.5M	$102.0M
YoY Change	12.25%	-1196.77%
FINANCING ACTIVITIES
Cash Dividend Paid	$10.60M
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-9.900M	-11.30M
YoY Change	-12.39%	10.78%
NET CHANGE
Cash From Operating Activities	-71.70M	-60.50M
Cash From Investing Activities	114.5M	102.0M
Cash From Financing Activities	-9.900M	-11.30M
Net Change In Cash	32.90M	30.20M
YoY Change	8.94%	-163.98%
FREE CASH FLOW
Cash From Operating Activities	-$71.70M	-$60.50M
Capital Expenditures	-$5.300M	-$8.400M
Free Cash Flow	-$66.40M	-$52.10M
YoY Change	27.45%	125.54%

Facts In Submission

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	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2020-06-30
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	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34634353	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34195250	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34551935	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34090372	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34634353	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34779991	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34551935	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34759548	shares
CY2020Q2	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	20100000	USD
CY2019Q2	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	14500000	USD
	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	-16000000.0	USD
	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	71300000	USD
CY2020Q2	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
CY2019Q2	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	2500000	USD
	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	6800000	USD
CY2020Q2	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	0	USD
CY2019Q2	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	2500000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	3600000	USD
	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	0	USD
	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	6800000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	20100000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	12000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-16000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	64500000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-6400000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	28800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-25200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	120000000.0	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-4200000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-300000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-7600000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-100000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	152900000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	41900000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	30100000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	98700000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	16500000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-1800000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	19900000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-4900000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	132200000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	43400000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	2600000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	103500000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	27000000.0	USD
CY2019Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	6700000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	5900000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	15800000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	2600000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-200000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	700000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-700000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	24400000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	6900000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	5200000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	16500000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	107800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	36500000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2600000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	87000000.0	USD
CY2020Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	101400000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	65300000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-27800000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	207000000.0	USD
CY2019Q1	us-gaap	Stockholders Equity StockholdersEquity	1880600000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	28800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	36800000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-300000	USD
CY2019Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	9300000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	700000	USD
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2019Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	11900000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	1929000000.0	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	1636800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-6400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	112000000.0	USD
CY2020Q2	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-4200000	USD
CY2020Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2200000	USD
CY2020Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	700000	USD
CY2020Q2	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	900000	USD
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10600000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1730000000.0	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1746700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	120000000.0	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	87100000	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-100000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	7800000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	10900000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1100000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	22700000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	1929000000.0	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1781100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-25200000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	5000000.0	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-7600000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5300000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6500000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1400000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	21300000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1730000000.0	USD
	us-gaap	Net Income Loss NetIncomeLoss	-25200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	120000000.0	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	14100000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	13800000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	5400000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	8800000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-18400000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	3200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-16000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	64500000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	20900000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-11400000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-200000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-100000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-2300000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-500000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-31200000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	161900000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-5100000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-3500000	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	115600000	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	136200000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	98500000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	83200000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	82200000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	103000000.0	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-140700000	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	80300000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	25500000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	4400000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	-70100000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	12800000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	34500000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	64500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-103100000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-4900000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	746000000.0	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	751600000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	255000000.0	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	168800000	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	8100000	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	32200000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	94200000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	31100000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1103600000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	888500000	USD
	argo	Payments To Acquire Equity Securities Fvni PaymentsToAcquireEquitySecuritiesFVNI	59500000	USD
	argo	Payments To Acquire Equity Securities Fvni PaymentsToAcquireEquitySecuritiesFVNI	32400000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	14300000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	38200000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	-5000000.0	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	-6300000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-212500000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-67700000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	7000000.0	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	9900000	USD
	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	38000000.0	USD
	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7600000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	15700000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	5000000.0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	22500000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	175800000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	70300000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1000000.0	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	900000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21300000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	22700000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-20300000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-21800000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-2500000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-500000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	49900000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	43100000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	137800000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139200000	USD
CY2020Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	187700000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	182300000	USD
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	Certain reclassifications have been made to financial information presented for prior years to conform to the current year’s presentation.
CY2019Q2	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	7500000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	8000000.0	USD
CY2020Q2	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	119100000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	316300000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	316800000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	1540700000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1523500000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	579800000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	592400000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	71200000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	71500000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	1180600000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	1203200000	USD
CY2020Q2	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	3688600000	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	32500000	USD
CY2020Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	3707400000	USD
CY2020Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	4833	security
CY2020Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	1509	security
CY2020Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	223	security
CY2019Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	0	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	32500000	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	800000	USD
CY2020Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	40200000	USD
CY2020Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	7800000	USD
CY2019Q2	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	2500000	USD
	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	6800000	USD
CY2020Q2	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	46500000	USD
CY2019Q2	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	11200000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	115500000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	23700000	USD
CY2020Q2	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	32200000	USD
CY2019Q2	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	12400000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	96400000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	27300000	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-11000000.0	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	600000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-12600000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	1300000	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	16800000	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	12600000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-22500000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	66800000	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	5800000	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	13200000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-35100000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	68100000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	20100000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	12000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-16000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	64500000	USD
CY2020Q2	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	6700000	USD
CY2019Q2	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	2600000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	-1300000	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-14700000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	12200000	USD
CY2020Q2	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	13400000	USD
CY2019Q2	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	9400000	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	52300000	USD
CY2020Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	136400000	USD
CY2019Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	43700000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	10200000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	103600000	USD
CY2020Q2	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	24400000	USD
CY2019Q2	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	6900000	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	5200000	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	16500000	USD
CY2020Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	112000000.0	USD
CY2019Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	36800000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	5000000.0	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	87100000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	100000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	USD
CY2020Q2	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	140900000	USD
CY2019Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	169900000	USD
CY2020Q2	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	344300000	USD
CY2019Q4	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	412800000	USD
CY2020Q2	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	715300000	USD
CY2019Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	775200000	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	14000000.0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	7700000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues	0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2020Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	21800000	USD
	argo	Amount Of Gains Or Losses For Period Included In Net Income Attributable To Change In Unrealized Gains Or Losses Relating To Assets Held At End Of Period AmountOfGainsOrLossesForPeriodIncludedInNetIncomeAttributableToChangeInUnrealizedGainsOrLossesRelatingToAssetsHeldAtEndOfPeriod	0	USD
CY2018Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	10400000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	3500000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-2000000.0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	600000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	1900000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues	0	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	400000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	14000000.0	USD
CY2019	argo	Amount Of Gains Or Losses For Period Included In Net Income Attributable To Change In Unrealized Gains Or Losses Relating To Assets Held At End Of Period AmountOfGainsOrLossesForPeriodIncludedInNetIncomeAttributableToChangeInUnrealizedGainsOrLossesRelatingToAssetsHeldAtEndOfPeriod	0	USD
CY2019Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	688200000	USD
CY2019Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	7900000	USD
	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	600000	USD
	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	0	USD
CY2020Q2	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	800200000	USD
CY2020Q2	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	8500000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	3104600000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	1100000	USD
	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	USD
	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2020Q2	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	2942800000	USD
CY2020Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	3600000	USD
CY2020Q2	argo	Credit Risk Rating Percent Rated A Or Better CreditRiskRatingPercentRatedAOrBetter	0.911
	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="text-align:justify;margin-top:6pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">The following table provides a reconciliation of reserves for losses and loss adjustment expenses (“LAE”):</span></div><div style="text-align:center;margin-top:6pt;margin-bottom:6pt;"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.861%;"><tr><td style="width:1.0%;"/><td style="width:68.792%;"/><td style="width:1.0%;"/><td style="width:0.1%;"/><td style="width:0.495%;"/><td style="width:0.1%;"/><td style="width:1.0%;"/><td style="width:11.908%;"/><td style="width:1.0%;"/><td style="width:0.1%;"/><td style="width:0.495%;"/><td style="width:0.1%;"/><td style="width:1.0%;"/><td style="width:11.910%;"/><td style="width:1.0%;"/></tr><tr><td colspan="3" style="background-color:rgb(255,255,255, 0.0);text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:rgb(255,255,255, 0.0);text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="9" style="padding-top:2px;padding-bottom:2px;background-color:rgb(255,255,255, 0.0);text-align:center;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:8pt;font-weight:700;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">For the Six Months Ended<br/>June 30,</span></td><td colspan="3" style="display:none;"/><td colspan="3" style="display:none;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:rgb(255,255,255, 0.0);text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:8pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">(in millions)</span></td><td colspan="3" style="background-color:rgb(255,255,255, 0.0);text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:rgb(255,255,255, 0.0);text-align:center;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:1pt;"><span style="font-size:8pt;font-weight:700;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2020</span></td><td colspan="3" style="background-color:rgb(255,255,255, 0.0);text-align:left;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:rgb(255,255,255, 0.0);text-align:center;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:1pt;"><span style="font-size:8pt;font-weight:700;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2019</span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Net reserves beginning of the year</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">$</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,722.7 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">$</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,562.9 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Net AIL reserves acquired</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">27.9 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">— </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="display:none;"/><td colspan="3" style="display:none;"/><td colspan="3" style="display:none;"/><td colspan="3" style="display:none;"/><td colspan="3" style="display:none;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Add:</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Losses and LAE incurred during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:12pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Current accident year</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">549.6 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">502.9 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:12pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Prior accident years</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">4.5 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">19.8 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Losses and LAE incurred during calendar year, net of reinsurance</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">554.1 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">522.7 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Deduct:</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:1pt;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Losses and LAE payments made during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:12pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Current accident year</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">125.3 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">89.8 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:12pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Prior accident years</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">451.5 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">432.4 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Losses and LAE payments made during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">576.8 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">522.2 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><div style="margin-top:3pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%;">Change in participation interest </span><sup style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:100%;vertical-align:top;">(1)</sup></div></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">33.0 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">(14.4)</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Foreign exchange adjustments</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">(8.5)</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">(13.0)</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Net reserves - end of period</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,752.4 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,536.0 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Add:</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Reinsurance recoverables on unpaid losses and LAE, end of period</span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,463.9 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#cceeff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td colspan="2" style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-left:1pt;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">2,199.7 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#cceeff;text-align:right;vertical-align:bottom;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr><tr><td colspan="3" style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">Gross reserves - end of period</span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-left:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">$</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">5,216.3 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td><td colspan="3" style="background-color:#ffffff;text-align:left;vertical-align:bottom;padding-left:1pt;padding-right:1pt;"/><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:left;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-left:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">$</span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-right:0%;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);">4,735.7 </span></td><td style="padding-top:2px;padding-bottom:2px;background-color:#ffffff;text-align:right;vertical-align:bottom;border-top:1pt solid #000000;border-bottom:3pt double #000000;padding-right:1pt;"><span style="font-size:10pt;font-weight:400;font-family:'Times New Roman',sans-serif;color:#000000;background-color:rgb(255,255,255, 0.0);"> </span></td></tr></table></div><div style="text-indent:-9pt;padding-left:9pt;text-align:justify;margin-top:3pt;"><sup style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:120%;vertical-align:top;">(1)</sup><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:2.94pt;">Amount represents the change in reserves due to changing our participation in Syndicates 1200 and 1910.</span></div>
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2722700000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2562900000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	27900000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	0	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	549600000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	502900000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	4500000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	19800000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	554100000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	522700000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	125300000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	89800000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	451500000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	432400000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	576800000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	522200000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	33000000.0	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	-14400000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	8500000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	13000000.0	USD
CY2020Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2752400000	USD
CY2019Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2536000000.0	USD
CY2020Q2	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2463900000	USD
CY2019Q2	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2199700000	USD
CY2020Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5216300000	USD
CY2019Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4735700000	USD
CY2020Q2	argo	Net Losses And Adjustment Expenses Related To Pandemic NetLossesAndAdjustmentExpensesRelatedToPandemic	17400000	USD
	argo	Net Losses And Adjustment Expenses Related To Pandemic NetLossesAndAdjustmentExpensesRelatedToPandemic	43600000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	4500000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	19800000	USD
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10600000	USD
CY2019Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2019Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	11900000	USD
	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	19200000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	16600000	USD
	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	-2600000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	82800000	USD
	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-4200000	USD
	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	87000000.0	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-6400000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	28800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-25200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	120000000.0	USD
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34634353	shares
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34195250	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34551935	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34090372	shares
CY2020Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
CY2019Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	584741	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	669176	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34634353	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34779991	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34551935	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34759548	shares
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.18
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.84
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.73
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.52
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.18
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.83
	argo	Other Corporate Expense Civil Penalties OtherCorporateExpenseCivilPenalties	900000	USD
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.73
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.45
CY2019Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
CY2020Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	5084	shares
CY2019Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	5084	shares
	us-gaap	Interest Paid Net InterestPaidNet	14800000	USD
	us-gaap	Interest Paid Net InterestPaidNet	16800000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	1600000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	1300000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	700000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	0	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	900000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	1300000	USD
CY2020Q2	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	57200000	USD
CY2019Q2	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	56700000	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	122500000	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	120000000.0	USD
CY2020Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	93300000	USD
CY2019Q2	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	91500000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	192200000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	180100000	USD
CY2020Q2	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	6500000	USD
CY2019Q2	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	7900000	USD
	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	14500000	USD
	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	16200000	USD
CY2020Q2	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	157000000.0	USD
CY2019Q2	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	156100000	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	329200000	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	316300000	USD
CY2020Q2	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-4400000	USD
CY2019Q2	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-5300000	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-200000	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-5300000	USD
CY2020Q2	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	161400000	USD
CY2019Q2	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	161400000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	329400000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	321600000	USD
CY2020Q2	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	2500000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	5800000	USD
CY2019Q2	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	7500000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	8000000.0	USD
CY2020Q2	argo	Other Corporate Expense Civil Penalties OtherCorporateExpenseCivilPenalties	900000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5700000	USD
CY2020Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	2.094
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	29600000	USD
CY2019Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.029
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-15900000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.587
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	129700000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.075
CY2020Q2	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	8600000	USD
CY2019Q2	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	3600000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	9400000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	18500000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	200000	USD
CY2019Q2	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	300000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	300000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	700000	USD
CY2020Q2	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	1500000	USD
CY2019Q2	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	100000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	-600000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	600000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	1000000.0	USD
CY2019Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	1000000.0	USD
	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2020Q2	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	0	USD
CY2019Q2	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	100000	USD
	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	100000	USD
	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	200000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2019Q2	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-600000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1200000	USD
CY2019Q2	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-2700000	USD
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-300000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-8300000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	12100000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	800000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9700000	USD
	argo	Net Operating Losses Carry Back Period NetOperatingLossesCarryBackPeriod	P2Y
	argo	Capital Losses Carry Back Period CapitalLossesCarryBackPeriod	P3Y
CY2020Q2	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q2	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2020Q2	us-gaap	Contractual Obligation ContractualObligation	96100000	USD
	argo	Contractual Obligation Period ContractualObligationPeriod	P13Y
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	433400000	USD
CY2019Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	431700000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	868400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	852200000	USD
CY2020Q2	us-gaap	Net Investment Income NetInvestmentIncome	1500000	USD
CY2019Q2	us-gaap	Net Investment Income NetInvestmentIncome	42800000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	37000000.0	USD
	us-gaap	Net Investment Income NetInvestmentIncome	76700000	USD
CY2020Q2	argo	Fee And Other Income FeeAndOtherIncome	2000000.0	USD
CY2019Q2	argo	Fee And Other Income FeeAndOtherIncome	2100000	USD
	argo	Fee And Other Income FeeAndOtherIncome	4100000	USD
	argo	Fee And Other Income FeeAndOtherIncome	4400000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	20100000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	12000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-16000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	64500000	USD
CY2020Q2	us-gaap	Revenues Revenues	457000000.0	USD
CY2019Q2	us-gaap	Revenues Revenues	488600000	USD
	us-gaap	Revenues Revenues	893500000	USD
	us-gaap	Revenues Revenues	997800000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	20100000	USD
CY2019Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	12000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-16000000.0	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	64500000	USD
CY2020Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-6400000	USD
CY2019Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	5300000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-3400000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	4600000	USD
CY2020Q2	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	2500000	USD
CY2019Q2	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	7500000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	5800000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	8000000.0	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5700000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	29600000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-15900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	129700000	USD
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	433400000	USD
CY2019Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	431700000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	868400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	852200000	USD
CY2020Q2	us-gaap	Assets Assets	10396700000	USD
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Files In Submission

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$ARGD
Argo Group International Holdings, Inc. Stock $argd

2020 Q2 Form 10-Q Financial Statement

#000162828020011889 Filed on August 06, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ARGD Argo Group International Holdings, Inc. Stock $argd

2020 Q2 Form 10-Q Financial Statement

#000162828020011889 Filed on August 06, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ARGD
Argo Group International Holdings, Inc. Stock $argd