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

$argd Overview Financials Valuation SEC Filings Company Website

2021 Q2 Form 10-Q Financial Statement

#000162828021016046 Filed on August 06, 2021

Income Statement

Concept	2021 Q2	2020 Q2	2020 Q1
Revenue	$547.7M	$452.7M	$434.4M
YoY Change	20.99%	-7.35%	-14.72%
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	$11.90M	$9.100M	$5.000M
YoY Change	30.77%	28.17%	-25.37%
% of Gross Profit
Operating Expenses	$458.9M	$438.1M	$451.4M
YoY Change	4.75%	-3.71%	12.88%
Operating Profit
YoY Change
Interest Expense	$5.700M	$7.000M	$7.800M
YoY Change	-18.57%	-25.53%	-9.3%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$78.70M	$5.900M	-$25.70M
YoY Change	1233.9%	-78.78%	-125.32%
Income Tax	$8.900M	$11.30M	-$1.000M
% Of Pretax Income	11.31%	191.53%
Net Earnings	$69.80M	-$5.400M	-$24.70M
YoY Change	-1392.59%	-120.0%	-128.2%
Net Earnings / Revenue	12.74%	-1.19%	-5.69%
Basic Earnings Per Share	$1.93	-$0.16	-$0.72
Diluted Earnings Per Share	$1.92	-$0.16	-$0.72
COMMON SHARES
Basic Shares Outstanding	34.82M shares	34.63M shares	34.47M shares
Diluted Shares Outstanding	35.01M shares	34.63M shares	34.47M shares

Balance Sheet

Concept	2021 Q2	2020 Q2	2020 Q1
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$190.7M	$187.7M	$158.7M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$78.80M	$87.00M	$89.00M
YoY Change	-9.43%	-23.01%	-22.61%
Goodwill	$147.3M	$156.5M	$161.4M
YoY Change	-5.88%	-11.58%	-8.81%
Intangibles	$60.50M	$91.10M	$91.50M
YoY Change	-33.59%	-1.62%	-1.72%
Long-Term Investments	$5.186B	$4.852B	$4.811B
YoY Change	6.88%	-0.53%	-1.9%
Other Assets	$35.50M	$32.00M	$60.00M
YoY Change	10.94%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$10.37B	$10.38B	$10.18B
YoY Change	-0.1%	2.22%	2.36%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$301.0M	$254.0M	$287.0M
YoY Change	18.5%	-37.28%	-23.87%
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	$306.3M	$281.0M	$305.0M
YoY Change	9.0%	-30.62%	-19.1%
LONG-TERM LIABILITIES
Long-Term Debt	$458.6M	$579.0M	$578.0M
YoY Change	-20.79%	0.0%	-0.34%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$458.6M	$579.0M	$578.0M
YoY Change	-20.79%	0.0%	-0.34%
TOTAL LIABILITIES
Total Short-Term Liabilities	$306.3M	$281.0M	$305.0M
Total Long-Term Liabilities	$458.6M	$579.0M	$578.0M
Total Liabilities	$8.470B	$8.671B	$8.564B
YoY Change	-2.31%	5.21%	6.03%
SHAREHOLDERS EQUITY
Retained Earnings	$756.5M	$734.4M	$750.4M
YoY Change	3.01%	-22.1%	-19.11%
Common Stock	$1.429B	$1.423B	$1.420B
YoY Change	0.48%	0.51%	-0.01%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$455.1M	$455.1M	$455.1M
YoY Change	0.0%	0.0%	0.0%
Treasury Stock Shares	11.32M shares	11.32M shares	11.32M shares
Shareholders Equity	$1.898B	$1.708B	$1.614B
YoY Change
Total Liabilities & Shareholders Equity	$10.37B	$10.38B	$10.18B
YoY Change	-0.1%	2.22%	2.36%

Cashflow Statement

Concept	2021 Q2	2020 Q2	2020 Q1
OPERATING ACTIVITIES
Net Income	$69.80M	-$5.400M	-$24.70M
YoY Change	-1392.59%	-120.0%	-128.2%
Depreciation, Depletion And Amortization	$11.90M	$9.100M	$5.000M
YoY Change	30.77%	28.17%	-25.37%
Cash From Operating Activities	-$82.70M	-$71.70M	-$31.40M
YoY Change	15.34%	18.51%	-156.47%
INVESTING ACTIVITIES
Capital Expenditures	-$5.600M	-$5.300M	$2.300M
YoY Change	5.66%	-36.9%	-68.49%
Acquisitions
YoY Change
Other Investing Activities	$134.7M	$119.8M	$2.800M
YoY Change	12.44%	8.51%	-86.07%
Cash From Investing Activities	$129.1M	$114.5M	$61.30M
YoY Change	12.75%	12.25%	-293.38%
FINANCING ACTIVITIES
Cash Dividend Paid	$11.10M	$10.60M	$10.70M
YoY Change	4.72%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-13.30M	-9.900M	-$10.40M
YoY Change	34.34%	-12.39%	-0.95%
NET CHANGE
Cash From Operating Activities	-82.70M	-71.70M	-$31.40M
Cash From Investing Activities	129.1M	114.5M	$61.30M
Cash From Financing Activities	-13.30M	-9.900M	-$10.40M
Net Change In Cash	33.10M	32.90M	$20.90M
YoY Change	0.61%	8.94%	54.81%
FREE CASH FLOW
Cash From Operating Activities	-$82.70M	-$71.70M	-$31.40M
Capital Expenditures	-$5.600M	-$5.300M	$2.300M
Free Cash Flow	-$77.10M	-$66.40M	-$33.70M
YoY Change	16.11%	27.45%	-169.77%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	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	2021-06-30
	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	90 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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	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-5200000	USD
CY2021Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	469000000.0	USD
CY2020Q2	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	446800000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	961400000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	906900000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	78700000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	109900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-19800000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8900000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10300000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	69800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-5400000	USD
	us-gaap	Net Income Loss NetIncomeLoss	99600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-30100000	USD
CY2021Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2700000	USD
CY2020Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	5300000	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	67100000	USD
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	67100000	USD
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-5400000	USD
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-5400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	0	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	94300000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	94300000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-30100000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-30100000	USD
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.93
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.16
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.72
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.87
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.92
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.16
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.70
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.87
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34820649	shares
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34634353	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34766948	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34551935	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	35012780	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34634353	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34983804	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34551935	shares
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	69800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-5400000	USD
	us-gaap	Net Income Loss NetIncomeLoss	99600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-30100000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	3400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-4200000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	2500000	USD
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-7600000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	1900000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	1900000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Net Unamortized Gain Loss Arising During Period Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansNetUnamortizedGainLossArisingDuringPeriodBeforeTax	0	USD
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	33300000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	152900000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-28800000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	30100000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	15200000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	16500000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	19200000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	19900000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	23400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	132200000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-43600000	USD
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	2600000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	0	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	400000	USD
	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	0	USD
CY2021Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	5500000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	27000000.0	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-6300000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	5900000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	1500000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	2600000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	2300000	USD
	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	700000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	4400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	24400000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-8200000	USD
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	5200000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	19000000.0	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	107800000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-35400000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2600000	USD
CY2021Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	88800000	USD
CY2020Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	102400000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	64200000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-32700000	USD
CY2020Q1	us-gaap	Stockholders Equity StockholdersEquity	1613500000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-5400000	USD
CY2020Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	112000000.0	USD
CY2020Q2	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-4200000	USD
CY2020Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2200000	USD
CY2020Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	700000	USD
CY2020Q2	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	900000	USD
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	10600000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1707700000	USD
CY2021Q1	us-gaap	Stockholders Equity StockholdersEquity	1821000000.0	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	69800000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	14100000	USD
CY2021Q2	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	4900000	USD
CY2021Q2	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	2300000	USD
CY2021Q2	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	100000	USD
CY2021Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	1000000.0	USD
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	1897900000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1763700000	USD
CY2021Q2	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	600000	USD
CY2021Q2	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	2700000	USD
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2021Q2	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	11100000	USD
	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-400000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-30100000	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	5000000.0	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-7600000	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5300000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6500000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1400000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	21300000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	1707700000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1857800000	USD
	us-gaap	Net Income Loss NetIncomeLoss	99600000	USD
	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	0	USD
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-39400000	USD
	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	4000000.0	USD
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	4500000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2400000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	1000000.0	USD
	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	5300000	USD
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.62
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	21900000	USD
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	1897900000	USD
	us-gaap	Net Income Loss NetIncomeLoss	99600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-30100000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	14800000	USD
	us-gaap	Depreciation And Amortization DepreciationAndAmortization	14100000	USD
CY2021Q2	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0.0	USD
	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	-400000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	4500000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	5400000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-6800000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-10900000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	37800000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-18300000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-50600000	USD
	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	20900000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-1700000	USD
	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-200000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-1100000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-2300000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-151300000	USD
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-37300000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	4400000	USD
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-5100000	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	15000000.0	USD
	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	115600000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	-170900000	USD
	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	98500000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	6600000	USD
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	82200000	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-22500000	USD
	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-148100000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	8500000	USD
	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	18800000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	23800000	USD
	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	-63800000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	16400000	USD
	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	37700000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-12500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-103100000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	616400000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	746000000.0	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	394800000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	255000000.0	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	33500000	USD
	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	8100000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	62300000	USD
	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	94200000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	983300000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1103600000	USD
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	1800000	USD
	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	59500000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	31500000	USD
	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	14300000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	-35900000	USD
	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	-5000000.0	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-12500000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-212500000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	-8800000	USD
	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	7000000.0	USD
	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	38000000.0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	13300000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	5000000.0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7600000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	37600000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	79100000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	175800000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	800000	USD
	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1000000.0	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	5300000	USD
	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21900000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	21300000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-26400000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-20300000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1700000	USD
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-2500000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	41900000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	49900000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	148800000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	137800000	USD
CY2021Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	190700000	USD
CY2020Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	187700000	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.
CY2021Q2	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	93000000.0	USD
CY2020Q4	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	140300000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearNetCarryingAmount	284500000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities Within One Year Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithinOneYearFairValue	288700000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsNetCarryingAmount	1596300000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After One Through Five Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1630200000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsNetCarryingAmount	714600000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After Five Through Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	729900000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsNetCarryingAmount	106700000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities After Ten Years Fair Value HeldToMaturitySecuritiesDebtMaturitiesAfterTenYearsFairValue	108400000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Net Carrying Amount HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount	1279100000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Debt Maturities Without Single Maturity Date Fair Value HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	1300500000	USD
CY2021Q2	us-gaap	Held To Maturity Securities HeldToMaturitySecurities	3981200000	USD
CY2021Q2	us-gaap	Held To Maturity Securities Fair Value HeldToMaturitySecuritiesFairValue	4057700000	USD
CY2021Q2	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	5244	security
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	477	security
CY2021Q2	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	78	security
CY2020Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	6600000	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	2000000.0	USD
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	-900000	USD
	argo	Debt Securities Available For Sale Allowance For Credit Loss Additional Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossAdditionalPeriodIncreaseDecrease	-1300000	USD
CY2021Q2	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	6400000	USD
CY2021Q2	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	26600000	USD
CY2020Q2	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	46500000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	34300000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	115500000	USD
CY2021Q2	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	22900000	USD
CY2020Q2	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	32700000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	31200000	USD
	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	97000000.0	USD
CY2021Q2	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	700000	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-11000000.0	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-1100000	USD
	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-12600000	USD
CY2021Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	20300000	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	15100000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	35800000	USD
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-24200000	USD
CY2021Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	21000000.0	USD
CY2020Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	4100000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	34700000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-36800000	USD
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	24700000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	17900000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	37800000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-18300000	USD
CY2021Q2	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	5200000	USD
CY2020Q2	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	6700000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	7900000	USD
	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	-1300000	USD
CY2021Q2	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	19500000	USD
CY2020Q2	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	11200000	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	29900000	USD
	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-17000000.0	USD
CY2021Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	18100000	USD
CY2020Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	136400000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	-48000000.0	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	10200000	USD
CY2020Q2	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	24400000	USD
CY2021Q2	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	4000000.0	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	-8600000	USD
	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	5200000	USD
CY2021Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	14100000	USD
CY2020Q2	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	112000000.0	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	-39400000	USD
	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	5000000.0	USD
CY2021Q2	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	190600000	USD
CY2020Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	189400000	USD
CY2021Q2	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	353000000.0	USD
CY2020Q4	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	409200000	USD
CY2021Q2	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	758100000	USD
CY2020Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	826100000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	24500000	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	6200000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	100000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	100000	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	3500000	USD
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2021Q2	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	27400000	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
CY2019Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	25600000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-5900000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-500000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	5300000	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	USD
CY2020	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	24500000	USD
CY2020	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
CY2020Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	679800000	USD
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	9400000	USD
	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-100000	USD
	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	600000	USD
	argo	Premium Receivable Allowance For Credit Loss Foreign Exchange Adjustments PremiumReceivableAllowanceForCreditLossForeignExchangeAdjustments	0	USD
CY2021Q2	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	681700000	USD
CY2021Q2	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	8700000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	3009000000.0	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	4100000	USD
	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	-300000	USD
	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2021Q2	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	2859900000	USD
CY2021Q2	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	3800000	USD
	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-top:6pt"><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><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;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 Six Months Ended<br/>June 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%">2021</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%">2020</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%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,906.1 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">2,722.7 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></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%">— </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%">27.9 </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 13pt;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%">579.4 </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%">549.6 </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 13pt;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%">(0.2)</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%">4.5 </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%">579.2 </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%">554.1 </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"><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%">Net reserve ceded - reinsurance to close transaction for years of account 2017 and prior</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;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%">207.8 </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%">— </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="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 13pt;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%">59.7 </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%">125.3 </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 13pt;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%">376.0 </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%">451.5 </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 payments made during current 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%">435.7 </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%">576.8 </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"><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">(2)</span></div></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%">12.8 </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%">33.0 </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"><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:#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%">6.1 </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%">(8.5)</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%">Net reserves - end of period</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%">2,860.7 </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%">2,752.4 </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"><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%">Reinsurance recoverables on unpaid losses and LAE, end of period</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%">2,377.9 </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%">2,463.9 </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%">Gross reserves - end of period</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;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%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">5,238.6 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;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%">5,216.3 </span></td><td style="background-color:#cceeff;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 reserves ceded under the reinsurance to close transaction with RiverStone for Lloyd’s years of account 2017 and prior, effective January 1, 2020.</span></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">(2)</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>
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2906100000	USD
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2722700000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	0	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	27900000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	579400000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	549600000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-200000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	4500000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	579200000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	554100000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Net Reserve Ceded In Reinsurance To Close Transaction LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNetReserveCededInReinsuranceToCloseTransaction	207800000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Net Reserve Ceded In Reinsurance To Close Transaction LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNetReserveCededInReinsuranceToCloseTransaction	0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	59700000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	125300000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	376000000.0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	451500000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	435700000	USD
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	576800000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	12800000	USD
	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	33000000.0	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	-6100000	USD
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	8500000	USD
CY2021Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2860700000	USD
CY2020Q2	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2752400000	USD
CY2021Q2	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2377900000	USD
CY2020Q2	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2463900000	USD
CY2021Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5238600000	USD
CY2020Q2	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5216300000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-200000	USD
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	4500000	USD
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2021Q2	us-gaap	Payments Of Dividends PaymentsOfDividends	11100000	USD
CY2021Q2	argo	Depositary Shares Dividends Per Share Declared DepositarySharesDividendsPerShareDeclared	0.437500
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.31
CY2020Q2	us-gaap	Payments Of Dividends PaymentsOfDividends	10600000	USD
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-18500000	USD
	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	16900000	USD
	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	-35400000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	16600000	USD
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	argo	Other Comprehensive Income Loss Netof Tax Including Cumulative Effectof Adoption OtherComprehensiveIncomeLossNetofTaxIncludingCumulativeEffectofAdoption	-2600000	USD
CY2021Q2	us-gaap	Net Income Loss NetIncomeLoss	69800000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	-5400000	USD
	us-gaap	Net Income Loss NetIncomeLoss	99600000	USD
	us-gaap	Net Income Loss NetIncomeLoss	-30100000	USD
CY2021Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	2700000	USD
CY2020Q2	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	5300000	USD
	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	67100000	USD
CY2021Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	67100000	USD
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-5400000	USD
CY2020Q2	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-5400000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	94300000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	94300000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-30100000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-30100000	USD
CY2021Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34820649	shares
CY2020Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34634353	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34766948	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34551935	shares
CY2021Q2	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	192131	shares
CY2020Q2	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	216856	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	shares
CY2021Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	35012780	shares
CY2020Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34634353	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34983804	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34551935	shares
CY2021Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.93
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.16
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.72
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.87
CY2021Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.92
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.16
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.70
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.87
CY2020Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
CY2021Q2	us-gaap	Treasury Stock Shares TreasuryStockShares	11315889	shares
CY2021Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	36219	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	48272	shares
	us-gaap	Interest Paid Net InterestPaidNet	10800000	USD
	us-gaap	Interest Paid Net InterestPaidNet	14800000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	8900000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	1600000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	100000	USD
	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	700000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	8800000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	900000	USD
CY2021Q2	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	71700000	USD
CY2020Q2	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	57200000	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	148200000	USD
	us-gaap	Noninterest Expense Commission Expense NoninterestExpenseCommissionExpense	122500000	USD
CY2021Q2	argo	Other Underwriting Acquisition And Insurance Expenses OtherUnderwritingAcquisitionAndInsuranceExpenses	104000000.0	USD
CY2020Q2	argo	Other Underwriting Acquisition And Insurance Expenses OtherUnderwritingAcquisitionAndInsuranceExpenses	98200000	USD
	argo	Other Underwriting Acquisition And Insurance Expenses OtherUnderwritingAcquisitionAndInsuranceExpenses	210600000	USD
	argo	Other Underwriting Acquisition And Insurance Expenses OtherUnderwritingAcquisitionAndInsuranceExpenses	205200000	USD
CY2021Q2	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	175700000	USD
CY2020Q2	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	155400000	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	358800000	USD
	argo	Underwriting Acquisition And Insurance Expense Gross UnderwritingAcquisitionAndInsuranceExpenseGross	327700000	USD
CY2021Q2	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-1600000	USD
CY2020Q2	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-4400000	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	5100000	USD
	argo	Net Supplementary Insurance Information Amortization Deferral Of Deferred Policy Acquisition Costs NetSupplementaryInsuranceInformationAmortizationDeferralOfDeferredPolicyAcquisitionCosts	-200000	USD
CY2021Q2	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	177300000	USD
CY2020Q2	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	159800000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	353700000	USD
	argo	Underwriting Acquisition And Insurance Expenses UnderwritingAcquisitionAndInsuranceExpenses	327900000	USD
CY2021Q2	argo	Deferred Tax Assets Change In Federal Tax Rate DeferredTaxAssetsChangeInFederalTaxRate	7400000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	78700000	USD
CY2021Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.113
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5900000	USD
CY2020Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	1.915
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	109900000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.093
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-19800000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.520
CY2021Q2	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	16500000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	8600000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	22800000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	9400000	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	100000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	200000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	300000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	300000	USD
CY2021Q2	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	-300000	USD
CY2020Q2	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	1500000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	-500000	USD
	argo	Income Tax Reconciliation Foreign Exchange Adjustments IncomeTaxReconciliationForeignExchangeAdjustments	-600000	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	0	USD
CY2020Q2	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
	us-gaap	Income Tax Reconciliation Nondeductible Expense Impairment Losses IncomeTaxReconciliationNondeductibleExpenseImpairmentLosses	1000000.0	USD
CY2021Q2	argo	Income Tax Reconciliation Withholding Taxes IncomeTaxReconciliationWithholdingTaxes	100000	USD
CY2020Q2	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	100000	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	600000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	0	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-1800000	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	0	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-1200000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-2000000.0	USD
	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-7400000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-7400000	USD
	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2021Q2	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	700000	USD
CY2020Q2	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	400000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-600000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	700000	USD
CY2021Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	8900000	USD
CY2020Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10300000	USD
	argo	Net Operating Losses Carry Back Period NetOperatingLossesCarryBackPeriod	P2Y
	argo	Capital Losses Carry Back Period CapitalLossesCarryBackPeriod	P3Y
CY2021Q2	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	-2000000.0	USD
CY2021Q2	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	600000	USD
	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-1800000	USD
CY2021Q2	us-gaap	Contractual Obligation ContractualObligation	67900000	USD
	argo	Contractual Obligation Period ContractualObligationPeriod	P12Y
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2021Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	470300000	USD
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	433400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	936400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	868400000	USD
CY2021Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-4400000	USD
CY2020Q2	us-gaap	Net Investment Income NetInvestmentIncome	1400000	USD
CY2021Q2	us-gaap	Net Investment Income NetInvestmentIncome	52700000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	97100000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	37000000.0	USD
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	24700000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	17900000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	37800000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-18300000	USD
CY2021Q2	us-gaap	Revenues Revenues	547700000	USD
CY2020Q2	us-gaap	Revenues Revenues	452700000	USD
	us-gaap	Revenues Revenues	1071300000	USD
	us-gaap	Revenues Revenues	887100000	USD
CY2021Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	24700000	USD
CY2020Q2	us-gaap	Gain Loss On Investments GainLossOnInvestments	17900000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	37800000	USD
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-18300000	USD
CY2020Q2	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-4300000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-5700000	USD
	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-5200000	USD
CY2021Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	78700000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	5900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	109900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-19800000	USD
CY2021Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	470300000	USD
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	433400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	936400000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	868400000	USD
CY2021Q2	us-gaap	Assets Assets	10368300000	USD
CY2020Q4	us-gaap	Assets Assets	10465800000	USD
CY2021Q2	argo	Assets Associated With Trade Capital Providers AssetsAssociatedWithTradeCapitalProviders	602300000	USD
CY2020Q4	argo	Assets Associated With Trade Capital Providers AssetsAssociatedWithTradeCapitalProviders	825900000	USD

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

2021 Q2 Form 10-Q Financial Statement

#000162828021016046 Filed on August 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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

2021 Q2 Form 10-Q Financial Statement

#000162828021016046 Filed on August 06, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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