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

$argd Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-Q Financial Statement

#000162828020015488 Filed on November 04, 2020

Income Statement

Concept	2020 Q4	2020 Q3	2019 Q3
Revenue	$516.9M	$481.8M	$487.4M
YoY Change	6.67%	-1.15%	-2.31%
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	$8.500M	$10.60M	$6.600M
YoY Change	23.19%	60.61%	-29.03%
% of Gross Profit
Operating Expenses	$512.0M	$494.5M	$507.7M
YoY Change	-9.78%	-2.6%	13.48%
Operating Profit
YoY Change
Interest Expense	-$6.000M	$6.900M	$7.700M
YoY Change	-171.43%	-10.39%	-2.53%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	-$1.100M	-$26.50M	-$27.10M
YoY Change	-98.92%	-2.21%	-159.82%
Income Tax	-$1.800M	-$3.400M	-$1.100M
% Of Pretax Income
Net Earnings	$700.0K	-$23.10M	-$26.00M
YoY Change	-100.68%	-11.15%	-164.04%
Net Earnings / Revenue	0.14%	-4.79%	-5.33%
Basic Earnings Per Share		-$0.72	-$0.76
Diluted Earnings Per Share	$20.17K	-$0.72	-$0.76
COMMON SHARES
Basic Shares Outstanding	34.68M shares	34.67M shares	34.30M shares
Diluted Shares Outstanding		34.67M shares	34.30M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$148.8M	$300.4M	$145.1M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets		$11.00M
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$130.4M	$84.00M	$109.0M
YoY Change	-7.12%	-22.94%
Goodwill	$147.3M	$156.5M	$177.0M
YoY Change	-8.74%	-11.58%	9.67%
Intangibles	$60.50M	$90.80M	$92.20M
YoY Change	-34.1%	-1.52%	-16.56%
Long-Term Investments	$5.256B	$5.006B	$5.127B
YoY Change	3.1%	-2.36%	5.39%
Other Assets	$24.00M	$30.00M
YoY Change	-7.69%
Total Long-Term Assets		$10.71B
YoY Change
TOTAL ASSETS
Total Short-Term Assets		$11.00M
Total Long-Term Assets		$10.71B
Total Assets	$10.47B	$10.72B	$10.43B
YoY Change	-0.41%	2.75%	12.44%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$263.0M	$301.0M	$404.0M
YoY Change	-19.82%	-25.5%	228.46%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$263.0M	$301.0M	$404.0M
YoY Change	-23.1%	-25.5%	208.4%
LONG-TERM LIABILITIES
Long-Term Debt	$459.0M	$457.0M	$579.0M
YoY Change	-20.73%	-21.07%	-0.34%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$459.0M	$457.0M	$579.0M
YoY Change	-20.73%	-21.07%	-18.91%
TOTAL LIABILITIES
Total Short-Term Liabilities	$263.0M	$301.0M	$404.0M
Total Long-Term Liabilities	$459.0M	$457.0M	$579.0M
Total Liabilities	$8.608B	$8.873B	$8.559B
YoY Change	-1.57%	3.67%	14.71%
SHAREHOLDERS EQUITY
Retained Earnings	$684.1M	$698.4M	$907.0M
YoY Change	-13.81%	-23.0%	-0.95%
Common Stock	$1.426B	$1.425B	$1.419B
YoY Change	0.27%	0.4%	0.35%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$455.1M	$455.1M	$455.1M
YoY Change	0.0%	0.0%	0.37%
Treasury Stock Shares	11.32M shares	11.32M shares	11.32M shares
Shareholders Equity	$1.858B	$1.849B	$1.875B
YoY Change
Total Liabilities & Shareholders Equity	$10.47B	$10.72B	$10.43B
YoY Change	-0.41%	2.75%	12.44%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2019 Q3
OPERATING ACTIVITIES
Net Income	$700.0K	-$23.10M	-$26.00M
YoY Change	-100.68%	-11.15%	-164.04%
Depreciation, Depletion And Amortization	$8.500M	$10.60M	$6.600M
YoY Change	23.19%	60.61%	-29.03%
Cash From Operating Activities	-$29.50M	$204.5M	$200.6M
YoY Change	128.68%	1.94%	90.87%
INVESTING ACTIVITIES
Capital Expenditures	-$4.400M	-$8.200M	-$7.200M
YoY Change	-37.14%	13.89%	-70.97%
Acquisitions
YoY Change
Other Investing Activities	-$100.6M	-$86.90M	-$222.3M
YoY Change	-529.91%	-60.91%	214.43%
Cash From Investing Activities	-$105.0M	-$95.10M	-$229.5M
YoY Change	-740.24%	-58.56%	140.31%
FINANCING ACTIVITIES
Cash Dividend Paid		$10.90M
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-13.00M	6.500M	-9.900M
YoY Change	28.71%	-165.66%	-48.17%
NET CHANGE
Cash From Operating Activities	-29.50M	204.5M	200.6M
Cash From Investing Activities	-105.0M	-95.10M	-229.5M
Cash From Financing Activities	-13.00M	6.500M	-9.900M
Net Change In Cash	-147.5M	115.9M	-38.80M
YoY Change	2134.85%	-398.71%	308.42%
FREE CASH FLOW
Cash From Operating Activities	-$29.50M	$204.5M	$200.6M
Capital Expenditures	-$4.400M	-$8.200M	-$7.200M
Free Cash Flow	-$25.10M	$212.7M	$207.8M
YoY Change	325.42%	2.36%	59.97%

Facts In Submission

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	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Amendment Flag AmendmentFlag	false
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2020-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-15259
	dei	Entity Registrant Name EntityRegistrantName	ARGO GROUP INTERNATIONAL HOLDINGS, LTD.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	D0
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	98-0214719
	dei	Entity Address Address Line1 EntityAddressAddressLine1	110 Pitts Bay Road
	dei	Entity Address City Or Town EntityAddressCityOrTown	Pembroke
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	HM08
	dei	Entity Address Country EntityAddressCountry	BM
	dei	City Area Code CityAreaCode	441
	dei	Local Phone Number LocalPhoneNumber	296-5858
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2019Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	513600000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1422300000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1381700000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-29400000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-26200000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-45300000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	103500000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	200000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9500000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8600000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-29600000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	-25100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
CY2020Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
CY2019Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-31600000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-25100000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56800000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	94900000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.91
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.73
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.78
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.91
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.73
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.64
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.73
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.93
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.93
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34667266	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34299999	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34590659	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34161016	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34667266	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34299999	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34590659	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34769622	shares
CY2020Q3	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	-5700000	USD
CY2019Q3	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	-1200000	USD
	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	-21700000	USD
	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	70100000	USD
CY2020Q3	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
CY2019Q3	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	5000000.0	USD
	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	11800000	USD
CY2020Q3	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	0	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	5000000.0	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	11800000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-5700000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-6200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-29600000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	-25100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-4700000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	0	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-12300000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-100000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	38200000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-7400000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	68300000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	91300000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-4500000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-2800000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	15400000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-7700000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	38000000.0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-4600000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	40600000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	98900000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	6500000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-700000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	12400000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	15100000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-500000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-300000	USD
	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	-1000000.0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	7000000.0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-400000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	12200000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	16100000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	31000000.0	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-4200000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	28400000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	82800000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1400000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-29300000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-26400000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	177700000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	1929000000.0	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	-25100000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-4200000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	0	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	3200000	USD
CY2019Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	300000	USD
CY2019Q3	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	600000	USD
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	9800000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1893400000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1730000000.0	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-29600000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	144000000.0	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	35700000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-4700000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	1500000	USD
CY2020Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	100000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	600000	USD
CY2020Q3	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	2000000.0	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10900000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1864500000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1746700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	82900000	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-100000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	11000000.0	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	11200000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1700000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.93
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	32500000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	1893400000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1781100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	144000000.0	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	40700000	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-12300000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	6800000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6600000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2000000.0	USD
	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	2000000.0	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.93
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	32200000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1864500000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	24700000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	20400000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	7700000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	11700000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-23200000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-2200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	1600000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-19400000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-400000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	0	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-3500000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	500000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	65100000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	282600000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	11700000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-7500000	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	120500000	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	147100000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	267600000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	194900000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	176800000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	197700000	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-102200000	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	204800000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-12800000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	7900000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	-7400000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	8500000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	4900000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	42500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	101400000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	195700000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	977500000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1046300000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	410300000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	292200000	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	18200000	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	66300000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	95500000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	67700000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1659300000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1535000000.0	USD
	argo	Payments To Acquire Equity Securities Fvni PaymentsToAcquireEquitySecuritiesFVNI	68300000	USD
	argo	Payments To Acquire Equity Securities Fvni PaymentsToAcquireEquitySecuritiesFVNI	49900000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	24500000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	54600000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	500000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	-2300000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-297800000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	0	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	9100000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	-1200000	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	15800000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	22900000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2700000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-29600000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	80700000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-159200000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	125000000.0	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	600000	USD
	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	144000000.0	USD
	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1400000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1400000	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	2000000.0	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32200000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32500000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-13800000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-31700000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-5700000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1100000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	162600000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5900000	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
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	300400000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	145100000	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.
CY2019Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	3700000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	11700000	USD
CY2020Q3	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	150200000	USD
CY2019Q4	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	158600000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	303400000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	305400000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	1682000000.0	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1691700000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	603400000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	622900000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	65800000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	67400000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	1192400000	USD
CY2020Q3	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	1227000000.0	USD
CY2020Q3	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	3847000000.0	USD
CY2020Q3	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	3914400000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	5011	security
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	1411	security
CY2020Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	174	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	15000000.0	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-15700000	USD
	argo	Debt Securities Available For Sale Allowance For Credit Loss Additional Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossAdditionalPeriodIncreaseDecrease	27500000	USD
CY2020Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	33700000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	5000000.0	USD
	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	11800000	USD
CY2020Q3	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	18000000.0	USD
CY2019Q3	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	11200000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	133500000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	34900000	USD
CY2020Q3	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	31000000.0	USD
CY2019Q3	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	15000000.0	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	127400000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	42300000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-3200000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	6400000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-15800000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	7700000	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	10500000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-8800000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-12000000.0	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	58000000.0	USD
CY2020Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	7300000	USD
CY2019Q3	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-2400000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-27800000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	65700000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-5700000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-6200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
CY2020Q3	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	-500000	USD
CY2019Q3	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	-300000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	-1700000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	11900000	USD
CY2020Q3	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-5200000	USD
CY2019Q3	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-5900000	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-20000000.0	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	46400000	USD
CY2020Q3	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	42700000	USD
CY2019Q3	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	-4600000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	52900000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	99000000.0	USD
CY2020Q3	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	7000000.0	USD
CY2019Q3	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	-400000	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	12200000	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	16100000	USD
CY2020Q3	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	35700000	USD
CY2019Q3	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	-4200000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	40700000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	82900000	USD
CY2020Q3	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	141900000	USD
CY2019Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	169900000	USD
CY2020Q3	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	353300000	USD
CY2019Q4	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	412800000	USD
CY2020Q3	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	727200000	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 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	-1600000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-500000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	12900000	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
CY2020Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	24800000	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	1000000.0	USD
	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	0	USD
	argo	Premium Receivable Allowance For Credit Loss Foreign Exchange Adjustments PremiumReceivableAllowanceForCreditLossForeignExchangeAdjustments	200000	USD
CY2020Q3	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	797000000.0	USD
CY2020Q3	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	9100000	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	100000	USD
	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2020Q3	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	3046500000	USD
CY2020Q3	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	3700000	USD
CY2020Q3	argo	Credit Risk Rating Percent Rated A Or Better CreditRiskRatingPercentRatedAOrBetter	0.897
	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-top:6pt;text-align:justify"><span style="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="margin-bottom:6pt;margin-top:6pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.861%"><tr><td style="width:1.0%"/><td style="width:69.692%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.495%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.808%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.495%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:12.810%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:0 1pt"/><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">For the Nine Months Ended<br/>September 30,</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(in millions)</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net reserves beginning of the year</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,722.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,562.9 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net AIL reserves acquired</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">27.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></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="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Add:</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Losses and LAE incurred during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 12pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Current accident year</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">876.9 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">799.9 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Prior accident years</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">6.1 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">61.6 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Losses and LAE incurred during calendar year, net of reinsurance</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">883.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">861.5 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Deduct:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Losses and LAE payments made during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Current accident year</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">188.2 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">163.6 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 12pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Prior accident years</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">632.7 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">615.8 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Losses and LAE payments made during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">820.9 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">779.4 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Change in participation interest </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:100%;position:relative;top:-3.5pt;vertical-align:baseline">(1)</span></div></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">33.0 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(14.4)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Foreign exchange adjustments</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">23.0 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(26.3)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net reserves - end of period</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,868.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,604.3 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Add:</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Reinsurance recoverables on unpaid losses and LAE, end of period</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,521.3 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,238.2 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Gross reserves - end of period</span></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">5,390.0 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">4,842.5 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="margin-top:3pt;padding-left:9pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:120%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span><span style="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	876900000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	799900000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	6100000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	61600000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	883000000.0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	861500000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	188200000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	163600000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	632700000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	615800000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	820900000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	779400000	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	-23000000.0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	26300000	USD
CY2020Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2868700000	USD
CY2019Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2604300000	USD
CY2020Q3	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2521300000	USD
CY2019Q3	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2238200000	USD
CY2020Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5390000000.0	USD
CY2019Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	4842500000	USD
CY2020Q3	argo	Net Losses And Adjustment Expenses Related To Pandemic NetLossesAndAdjustmentExpensesRelatedToPandemic	16900000	USD
	argo	Net Losses And Adjustment Expenses Related To Pandemic NetLossesAndAdjustmentExpensesRelatedToPandemic	60500000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	6100000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	61600000	USD
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10900000	USD
CY2020Q3	argo	Depositary Shares Dividends Per Share Declared DepositarySharesDividendsPerShareDeclared	0.330556
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10900000	USD
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
CY2020Q3	argo	Depositary Shares Shares Issued DepositarySharesSharesIssued	6000000	shares
CY2020Q3	argo	Depositary Share Liquidation Preference Per Share DepositaryShareLiquidationPreferencePerShare	25
CY2020Q3	argo	Proceeds From Sale Of Depositary Shares ProceedsFromSaleOfDepositaryShares	144000000	USD
CY2020Q3	us-gaap	Extinguishment Of Debt Amount ExtinguishmentOfDebtAmount	125000000	USD
CY2020Q3	argo	Preferred Stock Per Depositary Share Amounts Of Preferred Dividends PreferredStockPerDepositaryShareAmountsOfPreferredDividends	1.75
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	43600000	USD
	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	15200000	USD
	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	28400000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	76100000	USD
	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-6700000	USD
	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	82800000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-29600000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	-25100000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
CY2020Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
CY2019Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-31600000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-25100000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56800000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	94900000	USD
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34667266	shares
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34299999	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34590659	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34161016	shares
CY2020Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
CY2019Q3	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	0	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	608606	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34667266	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34299999	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34590659	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34769622	shares
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.91
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.73
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.64
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.78
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.91
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.73
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.64
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.73
CY2020Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
CY2019Q3	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2331	shares
	us-gaap	Interest Paid Net InterestPaidNet	21000000.0	USD
	us-gaap	Interest Paid Net InterestPaidNet	26500000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	46000000.0	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	4800000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	4700000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	1600000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	100000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	44400000	USD
CY2020Q3	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	79400000	USD
CY2019Q3	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	58000000.0	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	201900000	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	178000000.0	USD
CY2020Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	92100000	USD
CY2019Q3	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	89200000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	284300000	USD
	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	269300000	USD
CY2020Q3	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	9400000	USD
CY2019Q3	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	10800000	USD
	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	23900000	USD
	argo	Premium Taxes Boards And Bureaus PremiumTaxesBoardsAndBureaus	27000000.0	USD
CY2020Q3	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	180900000	USD
CY2019Q3	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	158000000.0	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	510100000	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	474300000	USD
CY2020Q3	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	16600000	USD
CY2019Q3	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-6000000.0	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	16400000	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-11300000	USD
CY2020Q3	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	164300000	USD
CY2019Q3	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	164000000.0	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	493700000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	485600000	USD
CY2020Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	400000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	6200000	USD
CY2019Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	3700000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	11700000	USD
	argo	Other Corporate Expense Civil Penalties OtherCorporateExpenseCivilPenalties	900000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-29400000	USD
CY2020Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.007
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-26200000	USD
CY2019Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.041
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	103500000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.084
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-45300000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.210
CY2020Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-6500000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-4100000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	2800000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	14400000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	200000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	400000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	500000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	1100000	USD
CY2020Q3	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	700000	USD
CY2019Q3	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	700000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	100000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	1300000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	0	USD
	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	900000	USD
	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-1800000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2019Q3	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
CY2020Q3	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	0	USD
CY2019Q3	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	0	USD
	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	100000	USD
	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	200000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	900000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	2700000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	0	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	2700000	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	0	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1200000	USD
	argo	Net Operating Losses Carry Back Period NetOperatingLossesCarryBackPeriod	P2Y
CY2019Q3	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	2200000	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1200000	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1600000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1400000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	500000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1200000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-6000000.0	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	200000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9500000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8600000	USD
	argo	Capital Losses Carry Back Period CapitalLossesCarryBackPeriod	P3Y
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1200000	USD
CY2020Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2700000	USD
CY2020Q3	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	500000	USD
CY2020Q3	us-gaap	Contractual Obligation ContractualObligation	86500000	USD
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	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2020Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	445500000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	451500000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1313900000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1303700000	USD
CY2020Q3	us-gaap	Net Investment Income NetInvestmentIncome	42000000.0	USD
CY2019Q3	us-gaap	Net Investment Income NetInvestmentIncome	40200000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	79000000.0	USD
	us-gaap	Net Investment Income NetInvestmentIncome	116900000	USD
CY2020Q3	argo	Fee And Other Income FeeAndOtherIncome	1700000	USD
CY2019Q3	argo	Fee And Other Income FeeAndOtherIncome	1900000	USD
	argo	Fee And Other Income FeeAndOtherIncome	5800000	USD
	argo	Fee And Other Income FeeAndOtherIncome	6300000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-5700000	USD
CY2019Q3	us-gaap	Revenues Revenues	487400000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-6200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
CY2020Q3	us-gaap	Revenues Revenues	483500000	USD
	us-gaap	Revenues Revenues	1377000000.0	USD
	us-gaap	Revenues Revenues	1485200000	USD
CY2020Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-5700000	USD
CY2019Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-6200000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
CY2020Q3	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-11600000	USD
CY2019Q3	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	1600000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-15000000.0	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	6200000	USD
CY2020Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	400000	USD
CY2019Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	3700000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	6200000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	11700000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-29400000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-26200000	USD
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	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	103500000	USD
CY2020Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	445500000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	451500000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1313900000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1303700000	USD
CY2020Q3	us-gaap	Assets Assets	10734300000	USD
CY2019Q4	us-gaap	Assets Assets	10514500000	USD
CY2020Q3	argo	Assets Associated With Trade Capital Providers AssetsAssociatedWithTradeCapitalProviders	800600000	USD
CY2019Q4	argo	Assets Associated With Trade Capital Providers AssetsAssociatedWithTradeCapitalProviders	916300000	USD
CY2020Q3	us-gaap	Debt Instrument Face Amount DebtInstrumentFaceAmount	143800000	USD
CY2019Q4	us-gaap	Debt Instrument Face Amount DebtInstrumentFaceAmount	143800000	USD
CY2020Q3	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	3700000	USD
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	3800000	USD
CY2020Q3	us-gaap	Senior Notes SeniorNotes	140100000	USD
CY2019Q4	us-gaap	Senior Notes SeniorNotes	140000000.0	USD
CY2020Q3	us-gaap	Investments Investments	5006000000.0	USD
CY2020Q3	us-gaap	Cash Cash	300400000	USD
CY2020Q3	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	22200000	USD
CY2020Q3	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	797000000.0	USD
CY2020Q3	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	3046500000	USD
CY2020Q3	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	247300000	USD
CY2020Q4	us-gaap	Income Tax Receivable IncomeTaxReceivable	11200000	USD
CY2020Q3	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	17000000.0	USD
CY2020Q3	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	170400000	USD
CY2020Q3	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	660900000	USD
CY2020Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	84400000	USD
CY2020Q3	us-gaap	Other Assets OtherAssets	358500000	USD
CY2020Q3	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	12500000	USD
CY2020Q3	us-gaap	Due From Affiliates DueFromAffiliates	0	USD
CY2020Q3	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2020Q3	us-gaap	Assets Assets	10734300000	USD
CY2020Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5390000000.0	USD
CY2020Q3	us-gaap	Unearned Premiums UnearnedPremiums	1574200000	USD
CY2020Q3	argo	Funds Held And Ceded Reinsurance Payable Net FundsHeldAndCededReinsurancePayableNet	1147600000	USD
CY2020Q3	us-gaap	Long Term Debt LongTermDebt	456900000	USD
CY2020Q3	argo	Accrued Underwriting Expenses And Other Liabilities AccruedUnderwritingExpensesAndOtherLiabilities	202800000	USD
CY2020Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	98300000	USD
CY2020Q3	us-gaap	Related Party Transaction Due From To Related Party RelatedPartyTransactionDueFromToRelatedParty	0	USD
CY2020Q3	us-gaap	Liabilities Liabilities	8869800000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	1864500000	USD
CY2020Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	10734300000	USD
CY2019Q4	us-gaap	Investments Investments	5099400000	USD
CY2019Q4	us-gaap	Cash Cash	137800000	USD
CY2019Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	25700000	USD
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CY2019Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	3104600000	USD
CY2019Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	253200000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	6100000	USD
CY2019Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	160200000	USD
CY2019Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	545000000.0	USD
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CY2019Q4	us-gaap	Assets Of Disposal Group Including Discontinued Operation AssetsOfDisposalGroupIncludingDiscontinuedOperation	15400000	USD
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CY2019Q4	us-gaap	Assets Assets	10514500000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5157600000	USD
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CY2019Q4	us-gaap	Accrued Income Taxes AccruedIncomeTaxes	800000	USD
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CY2020Q3	us-gaap	Interest Expense InterestExpense	6800000	USD
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CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	200000	USD
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CY2019Q3	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	164000000.0	USD
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CY2020Q3	argo	Equity In Undistributed Net Income Loss Of Subsidiaries EquityInUndistributedNetIncomeLossOfSubsidiaries	0	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	-29600000	USD
CY2020Q3	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
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CY2019Q3	argo	Fee And Other Income FeeAndOtherIncome	1900000	USD
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CY2019Q3	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	3700000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	7500000	USD
CY2019Q3	argo	Fee And Other Expense FeeAndOtherExpense	1200000	USD
CY2019Q3	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	1600000	USD
CY2019Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	513600000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-26200000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-1100000	USD
CY2019Q3	argo	Net Income Loss Before Equity In Earnings Of Subsidiaries NetIncomeLossBeforeEquityInEarningsOfSubsidiaries	-25100000	USD
CY2019Q3	argo	Equity In Undistributed Net Income Loss Of Subsidiaries EquityInUndistributedNetIncomeLossOfSubsidiaries	0	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	-25100000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1313900000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	79000000.0	USD
	argo	Fee And Other Income FeeAndOtherIncome	5800000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-21700000	USD
	us-gaap	Revenues Revenues	1377000000.0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	883000000.0	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	493700000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	6200000	USD
	us-gaap	Interest Expense InterestExpense	21300000	USD
	argo	Fee And Other Expense FeeAndOtherExpense	3100000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-15000000.0	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1422300000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-45300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9500000	USD
	argo	Net Income Loss Before Equity In Earnings Of Subsidiaries NetIncomeLossBeforeEquityInEarningsOfSubsidiaries	-54800000	USD
	argo	Equity In Undistributed Net Income Loss Of Subsidiaries EquityInUndistributedNetIncomeLossOfSubsidiaries	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	-54800000	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2000000.0	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-56800000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	1303700000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	116900000	USD
	argo	Fee And Other Income FeeAndOtherIncome	6300000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	58300000	USD
	us-gaap	Revenues Revenues	1485200000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	861500000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	485600000	USD
	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	11700000	USD
	us-gaap	Interest Expense InterestExpense	25300000	USD
	argo	Fee And Other Expense FeeAndOtherExpense	3800000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	6200000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	1381700000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	103500000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8600000	USD
	argo	Net Income Loss Before Equity In Earnings Of Subsidiaries NetIncomeLossBeforeEquityInEarningsOfSubsidiaries	94900000	USD
	argo	Equity In Undistributed Net Income Loss Of Subsidiaries EquityInUndistributedNetIncomeLossOfSubsidiaries	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	94900000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	101400000	USD
	argo	Proceeds From Sale Of Investments ProceedsFromSaleOfInvestments	1091200000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	410300000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	1752100000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits Voluntary Pools Shortterm Investments PaymentsForProceedsFromChangeInForeignRegulatoryDepositsVoluntaryPoolsShorttermInvestments	-297300000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	9100000	USD
	us-gaap	Payments To Acquire Additional Interest In Subsidiaries PaymentsToAcquireAdditionalInterestInSubsidiaries	0	USD
	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	38000000.0	USD
	argo	Payments For Proceeds From Purchases Of Fixed Asset And Other Investing Activities PaymentsForProceedsFromPurchasesOfFixedAssetAndOtherInvestingActivities	13100000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	80700000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	125000000.0	USD
	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	144000000.0	USD
	us-gaap	Proceeds From Contributed Capital ProceedsFromContributedCapital	0	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1400000	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	2000000.0	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32200000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-13800000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-5700000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	162600000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	137800000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	300400000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	195700000	USD
	argo	Proceeds From Sale Of Investments ProceedsFromSaleOfInvestments	1180300000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	292200000	USD
	us-gaap	Payments To Acquire Investments PaymentsToAcquireInvestments	1639500000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits Voluntary Pools Shortterm Investments PaymentsForProceedsFromChangeInForeignRegulatoryDepositsVoluntaryPoolsShorttermInvestments	-2300000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	-1200000	USD
	argo	Payments For Proceeds From Purchases Of Fixed Asset And Other Investing Activities PaymentsForProceedsFromPurchasesOfFixedAssetAndOtherInvestingActivities	-6700000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-159200000	USD
	argo	Paymentfor Intercompany Note PaymentforIntercompanyNote	0	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	600000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1400000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32500000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-31700000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1100000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5900000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139200000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	145100000	USD

Files In Submission

Name	View Source	Status
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0001628280-20-015488-index.html	Edgar Link	pending
0001628280-20-015488.txt	Edgar Link	pending
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argo-20200930_lab.xml	Edgar Link	unprocessable
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Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
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report.css	Edgar Link	pending
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$ARGD
Argo Group International Holdings, Inc. Stock $argd

2020 Q4 Form 10-Q Financial Statement

#000162828020015488 Filed on November 04, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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

2020 Q4 Form 10-Q Financial Statement

#000162828020015488 Filed on November 04, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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