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

$argd Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-K Financial Statement

#000162828022006331 Filed on March 16, 2022

Income Statement

Concept	2021 Q4	2021	2020 Q4
Revenue	$530.7M	$2.130B	$516.9M
YoY Change	2.67%	12.74%	6.67%
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	$14.90M	$23.90M	$8.500M
YoY Change	75.29%	-0.83%	23.19%
% of Gross Profit
Operating Expenses	$617.8M	$2.059B	$512.0M
YoY Change	20.66%	8.48%	-9.78%
Operating Profit
YoY Change
Interest Expense	-$2.500M	$21.60M	-$6.000M
YoY Change	-58.33%	-19.7%	-171.43%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	-$132.8M	$5.300M	-$1.100M
YoY Change	11972.73%	-111.42%	-98.92%
Income Tax	-$17.50M	-$1.400M	-$1.800M
% Of Pretax Income		-26.42%
Net Earnings	-$115.3M	$6.700M	$700.0K
YoY Change	-16571.43%	-112.38%	-100.68%
Net Earnings / Revenue	-21.73%	0.31%	0.14%
Basic Earnings Per Share		-$0.11
Diluted Earnings Per Share	-$3.306M	-$0.11	$20.17K
COMMON SHARES
Basic Shares Outstanding	34.87M shares	34.82M shares	34.68M shares
Diluted Shares Outstanding		34.82M shares

Balance Sheet

Concept	2021 Q4	2021	2020 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$146.1M		$148.8M
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	$67.50M	$148.9M	$130.4M
YoY Change	-48.24%	-29.76%	-7.12%
Goodwill	$147.3M		$147.3M
YoY Change	0.0%		-8.74%
Intangibles	$17.30M		$60.50M
YoY Change	-71.4%		-34.1%
Long-Term Investments	$5.323B	$5.323B	$5.256B
YoY Change	1.27%	1.27%	3.1%
Other Assets	$73.60M	$73.60M	$24.00M
YoY Change	206.67%	206.67%	-7.69%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$10.32B	$10.32B	$10.47B
YoY Change	-1.41%	-1.42%	-0.41%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$264.3M	$264.3M	$263.0M
YoY Change	0.49%	0.49%	-19.82%
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	$264.3M	$264.3M	$263.0M
YoY Change	0.49%	0.49%	-23.1%
LONG-TERM LIABILITIES
Long-Term Debt	$455.5M	$455.5M	$459.0M
YoY Change	-0.76%	-0.76%	-20.73%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$455.5M	$455.5M	$459.0M
YoY Change	-0.76%	-0.76%	-20.73%
TOTAL LIABILITIES
Total Short-Term Liabilities	$264.3M	$264.3M	$263.0M
Total Long-Term Liabilities	$455.5M	$455.5M	$459.0M
Total Liabilities	$8.583B	$8.583B	$8.608B
YoY Change	-0.3%	-0.3%	-1.57%
SHAREHOLDERS EQUITY
Retained Earnings	$636.4M		$684.1M
YoY Change	-6.97%		-13.81%
Common Stock	$1.433B		$1.426B
YoY Change	0.45%		0.27%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$455.1M		$455.1M
YoY Change	0.0%		0.0%
Treasury Stock Shares	11.32M shares		11.32M shares
Shareholders Equity	$1.735B	$1.735B	$1.858B
YoY Change
Total Liabilities & Shareholders Equity	$10.32B	$10.32B	$10.47B
YoY Change	-1.41%	-1.42%	-0.41%

Cashflow Statement

Concept	2021 Q4	2021	2020 Q4
OPERATING ACTIVITIES
Net Income	-$115.3M	$6.700M	$700.0K
YoY Change	-16571.43%	-112.38%	-100.68%
Depreciation, Depletion And Amortization	$14.90M	$23.90M	$8.500M
YoY Change	75.29%	-0.83%	23.19%
Cash From Operating Activities	$58.90M	$99.70M	-$29.50M
YoY Change	-299.66%	38.66%	128.68%
INVESTING ACTIVITIES
Capital Expenditures			-$4.400M
YoY Change			-37.14%
Acquisitions
YoY Change
Other Investing Activities	-$106.5M	-$7.700M	-$100.6M
YoY Change	5.86%	-43.38%	-529.91%
Cash From Investing Activities	-$106.5M	-$55.90M	-$105.0M
YoY Change	1.43%	130.04%	-740.24%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-13.50M	-$52.90M	-13.00M
YoY Change	3.85%	97.39%	28.71%
NET CHANGE
Cash From Operating Activities	58.90M	$99.70M	-29.50M
Cash From Investing Activities	-106.5M	-$55.90M	-105.0M
Cash From Financing Activities	-13.50M	-$52.90M	-13.00M
Net Change In Cash	-61.10M	-$2.700M	-147.5M
YoY Change	-58.58%	-124.55%	2134.85%
FREE CASH FLOW
Cash From Operating Activities	$58.90M	$99.70M	-$29.50M
Capital Expenditures			-$4.400M
Free Cash Flow			-$25.10M
YoY Change			325.42%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2021	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2021
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CY2021	dei	Document Type DocumentType	10-K
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CY2021	dei	Document Period End Date DocumentPeriodEndDate	2021-12-31
CY2021	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2021	dei	Document Transition Report DocumentTransitionReport	false
CY2021	dei	Entity File Number EntityFileNumber	1-15259
CY2021	dei	Entity Registrant Name EntityRegistrantName	ARGO GROUP INTERNATIONAL HOLDINGS, LTD.
CY2021	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	D0
CY2021	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	98-0214719
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14100000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	6700000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-54100000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-14100000	USD
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	10500000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	4600000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	0	USD
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CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-3800000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-58700000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-58700000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	-14100000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-14100000	USD
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CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.24
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CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34614813	shares
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CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34816160	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34614813	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	34205954	shares
CY2021	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	32600000	USD
CY2020	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	-3600000	USD
CY2019	us-gaap	Debt And Equity Securities Gain Loss Excluding Other Than Temporary Impairment Loss DebtAndEquitySecuritiesGainLossExcludingOtherThanTemporaryImpairmentLoss	100400000	USD
CY2021	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
CY2020	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	0	USD
CY2019	argo	Other Than Temporary Impairment Losses Fixed Maturities OtherThanTemporaryImpairmentLossesFixedMaturities	20300000	USD
CY2021	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	0	USD
CY2020	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	0	USD
CY2019	us-gaap	Other Than Temporary Impairment Loss Debt Securities Portion Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesPortionRecognizedInEarnings	20300000	USD
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	32600000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	-3600000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	80100000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	6700000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-54100000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-14100000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	2600000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-15300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-200000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-1900000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	600000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	1800000	USD
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-94700000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	95200000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	88000000.0	USD
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	12200000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	12800000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Before Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesBeforeTax	-9900000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-102400000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	66500000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	95900000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-400000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	400000	USD
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-17300000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	16500000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	14200000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	4200000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-1200000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-21100000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	16400000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	15000000.0	USD
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-81300000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	50100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	80900000	USD
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-74600000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-4000000.0	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	66800000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	1735000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-14100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	82500000	USD
CY2019	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-1600000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	16300000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	13800000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2500000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.24
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	43100000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	1763700000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-54100000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	144000000.0	USD
CY2020	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	65900000	USD
CY2020	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	-15800000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	8100000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6700000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2500000	USD
CY2020	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	4600000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.24
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	43000000.0	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1857800000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	6700000	USD
CY2021	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-85400000	USD
CY2021	us-gaap	Other Comprehensive Income Other Net Of Tax OtherComprehensiveIncomeOtherNetOfTax	4100000	USD
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	7100000	USD
CY2021	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	2800000	USD
CY2021	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2100000	USD
CY2021	us-gaap	Dividends Preferred Stock Cash DividendsPreferredStockCash	10500000	USD
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.24
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	43900000	USD
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1735200000	USD
CY2021	us-gaap	Net Income Loss NetIncomeLoss	6700000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	-54100000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-14100000	USD
CY2021	us-gaap	Depreciation And Amortization DepreciationAndAmortization	43400000	USD
CY2020	us-gaap	Depreciation And Amortization DepreciationAndAmortization	33200000	USD
CY2019	us-gaap	Depreciation And Amortization DepreciationAndAmortization	27300000	USD
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	8000000.0	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	8700000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	16900000	USD
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-38600000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-21600000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-23500000	USD
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	32600000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	-3600000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	80100000	USD
CY2021	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-95500000	USD
CY2020	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-8600000	USD
CY2019	argo	Undistributed Earnings From Alternative Investment Portfolio UndistributedEarningsFromAlternativeInvestmentPortfolio	-19900000	USD
CY2021	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-23300000	USD
CY2020	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-5500000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-7200000	USD
CY2021	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	43200000	USD
CY2020	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	0	USD
CY2019	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	15600000	USD
CY2021	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-800000	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-3900000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-1500000	USD
CY2021	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-47400000	USD
CY2020	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-84800000	USD
CY2019	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	455100000	USD
CY2021	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-800000	USD
CY2020	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	4600000	USD
CY2019	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	-7000000.0	USD
CY2021	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	-65700000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	33200000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Reinsurance Premiums IncreaseDecreaseInPrepaidReinsurancePremiums	87800000	USD
CY2021	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	210800000	USD
CY2020	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	280200000	USD
CY2019	us-gaap	Increase Decrease In Future Policy Benefit Reserves IncreaseDecreaseInFuturePolicyBenefitReserves	509000000.0	USD
CY2021	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	7200000	USD
CY2020	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	63700000	USD
CY2019	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	111700000	USD
CY2021	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-207300000	USD
CY2020	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	-238200000	USD
CY2019	argo	Increase Decrease In Reinsurance Payables And Funds Held IncreaseDecreaseInReinsurancePayablesAndFundsHeld	243300000	USD
CY2021	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-4500000	USD
CY2020	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	-17500000	USD
CY2019	us-gaap	Increase Decrease In Accrued Income Taxes Payable IncreaseDecreaseInAccruedIncomeTaxesPayable	11400000	USD
CY2021	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	3000000.0	USD
CY2020	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	-43700000	USD
CY2019	argo	Increase Decrease In Accrued Underwriting Expenses IncreaseDecreaseInAccruedUnderwritingExpenses	-10600000	USD
CY2021	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-17900000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-9800000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	77000000.0	USD
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	99700000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	71900000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	182800000	USD
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	992900000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1080000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1394300000	USD
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	717700000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	569800000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	522200000	USD
CY2021	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	125800000	USD
CY2020	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	25400000	USD
CY2019	argo	Proceedsfrom Sale And Maturity Of Equity Securities Fvni ProceedsfromSaleAndMaturityOfEquitySecuritiesFVNI	374700000	USD
CY2021	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	212300000	USD
CY2020	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	103900000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	83100000	USD
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1932900000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2038100000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1859100000	USD
CY2021	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	5300000	USD
CY2020	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	78900000	USD
CY2019	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	61200000	USD
CY2021	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	47400000	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	35500000	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	63700000	USD
CY2021	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	27100000	USD
CY2020	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	5400000	USD
CY2019	argo	Payments For Proceeds From Change In Foreign Regulatory Deposits And Voluntary Pools PaymentsForProceedsFromChangeInForeignRegulatoryDepositsAndVoluntaryPools	0	USD
CY2021	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	116400000	USD
CY2020	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-285400000	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	490400000	USD
CY2021	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	-1200000	USD
CY2020	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	9400000	USD
CY2019	argo	Increase Decrease In Settlements Of Foreign Currency Exchange Forward Contracts IncreaseDecreaseInSettlementsOfForeignCurrencyExchangeForwardContracts	300000	USD
CY2021	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2020	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	28300000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	0	USD
CY2021	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2020	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	38000000.0	USD
CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2021	argo	Payments For Proceeds From Property Plant And Equipment PaymentsForProceedsFromPropertyPlantAndEquipment	18000000.0	USD
CY2020	argo	Payments For Proceeds From Property Plant And Equipment PaymentsForProceedsFromPropertyPlantAndEquipment	-20200000	USD
CY2019	argo	Payments For Proceeds From Property Plant And Equipment PaymentsForProceedsFromPropertyPlantAndEquipment	-29900000	USD
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-7700000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-13600000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	13100000	USD
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-55900000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-24300000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-142800000	USD
CY2021	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	0	USD
CY2020	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	125000000.0	USD
CY2019	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	600000	USD
CY2021	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-100000	USD
CY2020	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	144000000.0	USD
CY2019	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	USD
CY2021	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1300000	USD
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1800000	USD
CY2019	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlans	1900000	USD
CY2021	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	10500000	USD
CY2020	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	4600000	USD
CY2019	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	0	USD
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	43700000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	43000000.0	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	43100000	USD
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-52900000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-26800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-41800000	USD
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	6400000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-9800000	USD
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2700000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	11000000.0	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-1900000	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
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139700000	USD
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	146100000	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
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2021	us-gaap	Contracts In Force Subject To Participation Through Reinsurance Percentage ContractsInForceSubjectToParticipationThroughReinsurancePercentage	1
CY2021	argo	Number Of Statutory Trust NumberOfStatutoryTrust	11	trust
CY2021	argo	Number Of Charitable Foundation NumberOfCharitableFoundation	1	foundation
CY2021	us-gaap	Malpractice Loss Contingency Return Of Premiums MalpracticeLossContingencyReturnOfPremiums	4700000	USD
CY2020	us-gaap	Malpractice Loss Contingency Return Of Premiums MalpracticeLossContingencyReturnOfPremiums	1500000	USD
CY2021	argo	Malpractice Loss Contingency Premiums Receivables Due MalpracticeLossContingencyPremiumsReceivablesDue	100000	USD
CY2020	argo	Malpractice Loss Contingency Premiums Receivables Due MalpracticeLossContingencyPremiumsReceivablesDue	100000	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	15600000	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	69000000.0	USD
CY2021Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	51700000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	112200000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	51700000	USD
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	0	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1100000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1700000	USD
CY2021Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	158800000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	163300000	USD
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	67500000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	130400000	USD
CY2021	us-gaap	Depreciation Depreciation	23900000	USD
CY2020	us-gaap	Depreciation Depreciation	24100000	USD
CY2019	us-gaap	Depreciation Depreciation	24400000	USD
CY2019	argo	Number Of Properties Held For Sale NumberOfPropertiesHeldForSale	4	property
CY2020	argo	Numberof Properties Sold NumberofPropertiesSold	2	property
	argo	Numberof Properties Sold NumberofPropertiesSold	2	property
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerNumberOfPositions	82	security
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-35300000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-37900000	USD
CY2021	us-gaap	Interest Paid Net InterestPaidNet	21800000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	26400000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	33100000	USD
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	43000000.0	USD
CY2020	us-gaap	Income Taxes Paid IncomeTaxesPaid	47700000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	24000000.0	USD
CY2021	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	2600000	USD
CY2020	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	1800000	USD
CY2019	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	100000	USD
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	40400000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	45900000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	23900000	USD
CY2021Q4	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	89600000	USD
CY2020Q4	argo	Fair Value Of Investments Assets Managed On Behalf Of Trade Capital Providers FairValueOfInvestmentsAssetsManagedOnBehalfOfTradeCapitalProviders	140300000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	281700000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	284600000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	1692000000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	1704800000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	710000000.0	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	711300000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	112600000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	111600000	USD
CY2021Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	4203200000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Without Single Maturity Date Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	4223300000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	5207	security
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Number Of Positions DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsNumberOfPositions	697	security
CY2019Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	15900000	USD
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	39300000	USD
CY2020	argo	Debt Securities Available For Sale Allowance For Credit Loss Additional Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossAdditionalPeriodIncreaseDecrease	23100000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	6600000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	6600000	USD
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	2900000	USD
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	3500000	USD
CY2021	argo	Debt Securities Available For Sale Allowance For Credit Loss Additional Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossAdditionalPeriodIncreaseDecrease	-3500000	USD
CY2021Q4	us-gaap	Debt Securities Available For Sale Amortized Cost Allowance For Credit Loss Excluding Accrued Interest DebtSecuritiesAvailableForSaleAmortizedCostAllowanceForCreditLossExcludingAccruedInterest	2500000	USD
CY2021	us-gaap	Investment Income Interest InvestmentIncomeInterest	98900000	USD
CY2020	us-gaap	Investment Income Interest InvestmentIncomeInterest	108600000	USD
CY2019	us-gaap	Investment Income Interest InvestmentIncomeInterest	129500000	USD
CY2021	us-gaap	Investment Income Dividend InvestmentIncomeDividend	3100000	USD
CY2020	us-gaap	Investment Income Dividend InvestmentIncomeDividend	2800000	USD
CY2019	us-gaap	Investment Income Dividend InvestmentIncomeDividend	11100000	USD
CY2021	argo	Income On Alternative Investments IncomeOnAlternativeInvestments	95500000	USD
CY2020	argo	Income On Alternative Investments IncomeOnAlternativeInvestments	10400000	USD
CY2019	argo	Income On Alternative Investments IncomeOnAlternativeInvestments	22400000	USD
CY2021	argo	Income On Short Term And Other Investments IncomeOnShortTermAndOtherInvestments	3300000	USD
CY2020	argo	Income On Short Term And Other Investments IncomeOnShortTermAndOtherInvestments	3900000	USD
CY2019	argo	Income On Short Term And Other Investments IncomeOnShortTermAndOtherInvestments	8900000	USD
CY2021	us-gaap	Insurance Investment Income InsuranceInvestmentIncome	200800000	USD
CY2020	us-gaap	Insurance Investment Income InsuranceInvestmentIncome	125700000	USD
CY2019	us-gaap	Insurance Investment Income InsuranceInvestmentIncome	171900000	USD
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	13200000	USD
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	13000000.0	USD
CY2019	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	20800000	USD
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	187600000	USD
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	112700000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	151100000	USD
CY2021	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	43700000	USD
CY2020	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	164100000	USD
CY2019	argo	Gross Realized Investment On Fixed Maturities And Other Gains GrossRealizedInvestmentOnFixedMaturitiesAndOtherGains	55300000	USD
CY2021	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	42800000	USD
CY2020	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	121000000.0	USD
CY2019	argo	Gross Realized Investment On Fixed Maturities And Other Losses GrossRealizedInvestmentOnFixedMaturitiesAndOtherLosses	43000000.0	USD
CY2021	argo	Other Realized Gains Losses On Investments OtherRealizedGainsLossesOnInvestments	-6300000	USD
CY2020	argo	Other Realized Gains Losses On Investments OtherRealizedGainsLossesOnInvestments	0	USD
CY2019	argo	Other Realized Gains Losses On Investments OtherRealizedGainsLossesOnInvestments	0	USD
CY2021	argo	Net Realized Investment On Fixed Maturities And Other Losses NetRealizedInvestmentOnFixedMaturitiesAndOtherLosses	-5700000	USD
CY2020	argo	Net Realized Investment On Fixed Maturities And Other Losses NetRealizedInvestmentOnFixedMaturitiesAndOtherLosses	-39900000	USD
CY2019	argo	Net Realized Investment On Fixed Maturities And Other Losses NetRealizedInvestmentOnFixedMaturitiesAndOtherLosses	-20300000	USD
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	71500000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-17100000	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	128900000	USD
CY2021	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-34100000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	10300000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-40800000	USD
CY2021	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	37400000	USD
CY2020	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-6800000	USD
CY2019	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	88100000	USD
CY2021	us-gaap	Gain Loss On Investments GainLossOnInvestments	32600000	USD
CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	-3600000	USD
CY2019	us-gaap	Gain Loss On Investments GainLossOnInvestments	80100000	USD
CY2021	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	6200000	USD
CY2020	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	1300000	USD
CY2019	argo	Income Tax Expense Benefit Related To Net Realized Investment And Other Gains IncomeTaxExpenseBenefitRelatedToNetRealizedInvestmentAndOtherGains	16200000	USD
CY2021	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	26400000	USD
CY2020	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	-4900000	USD
CY2019	argo	Net Realized Investment Gains Losses Net Of Income Taxes NetRealizedInvestmentGainsLossesNetOfIncomeTaxes	63900000	USD
CY2021	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	-106900000	USD
CY2020	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	82400000	USD
CY2019	argo	Gains Losses In Investment Unrealized Appreciation Depreciation Before Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationBeforeTax	97900000	USD
CY2021	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	-21500000	USD
CY2020	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	16500000	USD
CY2019	argo	Income Tax Expense Benefit Related To Unrealized Appreciation Depreciation Net Tax Effects IncomeTaxExpenseBenefitRelatedToUnrealizedAppreciationDepreciationNetTaxEffects	15400000	USD
CY2021	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	-85400000	USD
CY2020	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	65900000	USD
CY2019	argo	Gains Losses In Investment Unrealized Appreciation Depreciation After Tax GainsLossesInInvestmentUnrealizedAppreciationDepreciationAfterTax	82500000	USD
CY2021Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	193900000	USD
CY2020Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged Under Letter Of Credit Facilities At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedUnderLetterOfCreditFacilitiesAtFairValue	189400000	USD
CY2021Q4	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	296800000	USD
CY2020Q4	argo	Securities And Letters Of Credit Pledged SecuritiesAndLettersOfCreditPledged	409200000	USD
CY2021Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	686300000	USD
CY2020Q4	us-gaap	Pledged Assets Separately Reported Securities Pledged As Collateral At Fair Value PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue	826100000	USD
CY2021Q4	argo	Securities And Letters Of Credit Pledged As Part Of Syndicate Minimum Amount SecuritiesAndLettersOfCreditPledgedAsPartOfSyndicateMinimumAmount	296800000	USD
CY2020Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	24500000	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3	1000000.0	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	0	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	4200000	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	-800000	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	1300000	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues	0	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	14100000	USD
CY2021	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	USD
CY2021Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	16100000	USD
CY2021	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
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5700000	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
CY2021	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-3100000	USD
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	600000	USD
CY2021	argo	Premium Receivable Allowance For Credit Loss Foreign Exchange Adjustments PremiumReceivableAllowanceForCreditLossForeignExchangeAdjustments	0	USD
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	648600000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	3009000000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	4100000	USD
CY2021	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	-300000	USD
CY2021	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2021Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	2966400000	USD
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	3800000	USD
CY2021	us-gaap	Lease Cost LeaseCost	18300000	USD
CY2020	us-gaap	Lease Cost LeaseCost	20300000	USD
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	81400000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	82000000.0	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	97700000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	95800000	USD
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P9Y6M3D
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y6M
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0353
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0377
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	14200000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	15300000	USD
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	6200000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	5400000	USD
CY2021	us-gaap	Sublease Income SubleaseIncome	2100000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	400000	USD
CY2021	us-gaap	Lease Cost LeaseCost	18300000	USD
CY2020	us-gaap	Lease Cost LeaseCost	20300000	USD
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	14900000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	15700000	USD
CY2021	argo	Operating Lease Payments Liability Reduction OperatingLeasePaymentsLiabilityReduction	12800000	USD
CY2020	argo	Operating Lease Payments Liability Reduction OperatingLeasePaymentsLiabilityReduction	12800000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	13800000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	13400000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	11800000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	11600000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	11200000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	54400000	USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	116200000	USD
CY2021Q4	argo	Lessee Operating Lease Lease Notyet Commenced Liability LesseeOperatingLeaseLeaseNotyetCommencedLiability		USD
CY2021Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	18500000	USD
CY2021	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	1400000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2600000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables On Paid Losses ReinsuranceRecoverablesOnPaidLosses	509100000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1314600000	USD
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	97700000	USD
CY2021	argo	Numberof Leased Properties Shortterm NumberofLeasedPropertiesShortterm	1	property
CY2021	argo	Numberof Leased Properties Shortterm NumberofLeasedPropertiesShortterm	1	property
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	3800000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	4100000	USD
CY2021Q4	argo	Collateral Under Reinsurance Agreements CollateralUnderReinsuranceAgreements	1085500000	USD
CY2020Q4	argo	Collateral Under Reinsurance Agreements CollateralUnderReinsuranceAgreements	1131400000	USD
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid Losses ReinsuranceRecoverablesOnPaidLosses	494600000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1208800000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1220700000	USD
CY2021	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	829600000	USD
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	941300000	USD
CY2019	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	1031100000	USD
CY2021	us-gaap	Direct Premiums Written DirectPremiumsWritten	2990600000	USD
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	2676100000	USD
CY2019	us-gaap	Direct Premiums Written DirectPremiumsWritten	2510400000	USD
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	1203900000	USD
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	1423200000	USD
CY2019	us-gaap	Ceded Premiums Written CededPremiumsWritten	1375600000	USD
CY2021	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	190600000	USD
CY2020	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	557200000	USD
CY2019	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	619800000	USD
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	1977300000	USD
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	1810100000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	1754600000	USD
CY2021	us-gaap	Direct Premiums Earned DirectPremiumsEarned	2917700000	USD
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	2660600000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	2412400000	USD
CY2021	us-gaap	Ceded Premiums Earned CededPremiumsEarned	1272700000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	1388600000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	1286700000	USD
CY2021	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	265100000	USD
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	508500000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	604000000.0	USD
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	1910100000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	1780500000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	1729700000	USD
CY2021	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.139
CY2020	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.286
CY2019	us-gaap	Premiums Percentage Assumed To Net PremiumsPercentageAssumedToNet	0.349
CY2021	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table provides a reconciliation of reserves for losses and loss adjustment expenses (“LAE”):</span></div><div style="text-align:justify"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:100.000%"><tr><td style="width:1.0%"/><td style="width:61.261%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.983%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.494%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.983%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.494%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:10.985%"/><td style="width:0.1%"/><td colspan="3" style="display:none"/></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:10pt;font-weight:400;line-height:100%"> </span></td><td colspan="15" 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 Years Ended December 31,</span></td><td colspan="3" style="display:none"/></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="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><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td><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%">Net reserves beginning of the year</span></td><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"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,562.9 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="display:none"/></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="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"/><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="display:none"/></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"/><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"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="display:none"/></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"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="display:none"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 12.25pt;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="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%">1,176.3 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,201.1 </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%">1,082.6 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="display:none"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12.25pt;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="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%">138.3 </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%">7.7 </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%">138.1 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><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%">Losses and LAE incurred during calendar year, net of reinsurance</span></td><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%">1,314.6 </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%">1,208.8 </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%">1,220.7 </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="display:none"/></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;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"/><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="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%">Losses and LAE payments made during current calendar year, net of reinsurance:</span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="display:none"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12.25pt;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="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%">180.8 </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%">253.4 </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%">224.3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="display:none"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 12.25pt;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="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%">688.4 </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%">866.4 </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%">806.0 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="display:none"/></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="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%">869.2 </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%">1,119.8 </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%">1,030.3 </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="display:none"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><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="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%">219.7 </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%">— </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%">— </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="display:none"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><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="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%">8.4 </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%">32.8 </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%">(14.4)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><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%">Foreign exchange adjustments</span></td><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%">(17.0)</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%">33.7 </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%">(16.2)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="display:none"/></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="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%">3,123.2 </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%">2,906.1 </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%">2,722.7 </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="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"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="3" style="display:none"/></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="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%">2,471.8 </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%">2,499.9 </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%">2,434.9 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><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%">Gross reserves - end of period</span></td><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%">5,595.0 </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%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">5,406.0 </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">5,157.6 </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="display:none"/></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:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">(1) </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Amount represents a decrease in reserves due to an RITC to RiverStone, see Note 2, recent acquisitions, disposals & other transactions.</span></div><div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:6.5pt;font-weight:400;line-height:120%;position:relative;top:-3.5pt;vertical-align:baseline">(2)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> Amount represents (decrease) increase in reserves due to change in our Syndicate 1200 and Syndicate 1910 participation.</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
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2562900000	USD
CY2021	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	0	USD
CY2020	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	27900000	USD
CY2019	argo	Liability For Unpaid Claims And Claims Adjustment Expense Acquired From Acquisition LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAcquiredFromAcquisition	0	USD
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	1176300000	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	1201100000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	1082600000	USD
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	138300000	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	7700000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	138100000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1314600000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1208800000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	1220700000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	180800000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	253400000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	224300000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	688400000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	866400000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	806000000.0	USD
CY2021	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	869200000	USD
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	1119800000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	1030300000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	219700000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	0	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	0	USD
CY2021	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	8400000	USD
CY2020	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	32800000	USD
CY2019	argo	Liability For Unpaid Claims And Claims Adjustment Expense Change In Participation Interest LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseChangeInParticipationInterest	-14400000	USD
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	17000000.0	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	-33700000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	16200000	USD
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	3123200000	USD
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
CY2021Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2471800000	USD
CY2020Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2499900000	USD
CY2019Q4	us-gaap	Reinsurance Receivables Incurred But Not Reported Claims ReinsuranceReceivablesIncurredButNotReportedClaims	2434900000	USD
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5595000000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5406000000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5157600000	USD
CY2021	argo	Loss Adjustment Expenses Related To Pandemic LossAdjustmentExpensesRelatedToPandemic	12400000	USD
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	138300000	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	7700000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	138100000	USD
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2021Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	3071600000	USD
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	2471800000	USD
CY2021Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claims Adjustment Expense Accumulated Unallocated Claim Adjustment Expense ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense	70400000	USD
CY2021Q4	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Aggregate Discount ShortdurationInsuranceContractsDiscountedLiabilitiesAggregateDiscount	18800000	USD
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	5595000000	USD
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CY2020Q4	us-gaap	Short Duration Contracts Discounted Liabilities Amount ShortDurationContractsDiscountedLiabilitiesAmount	278800000	USD
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CY2021Q4	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Aggregate Discount ShortdurationInsuranceContractsDiscountedLiabilitiesAggregateDiscount	18800000	USD
CY2020Q4	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Aggregate Discount ShortdurationInsuranceContractsDiscountedLiabilitiesAggregateDiscount	17800000	USD
CY2019Q4	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Aggregate Discount ShortdurationInsuranceContractsDiscountedLiabilitiesAggregateDiscount	17900000	USD
CY2021	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Interest Accretion ShortdurationInsuranceContractsDiscountedLiabilitiesInterestAccretion	1100000	USD
CY2020	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Interest Accretion ShortdurationInsuranceContractsDiscountedLiabilitiesInterestAccretion	1900000	USD
CY2019	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Interest Accretion ShortdurationInsuranceContractsDiscountedLiabilitiesInterestAccretion	1500000	USD
CY2021Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	63800000	USD
CY2020Q4	us-gaap	Liability For Asbestos And Environmental Claims Gross LiabilityForAsbestosAndEnvironmentalClaimsGross	59300000	USD
CY2021Q4	argo	Gross Reserve For Discontinuation Of Certain Lines Of Business GrossReserveForDiscontinuationOfCertainLinesOfBusiness	261200000	USD
CY2020Q4	argo	Gross Reserve For Discontinuation Of Certain Lines Of Business GrossReserveForDiscontinuationOfCertainLinesOfBusiness	236500000	USD
CY2021	argo	Asbestos And Environmental Underwriting Losses AsbestosAndEnvironmentalUnderwritingLosses	14700000	USD
CY2020	argo	Asbestos And Environmental Underwriting Losses AsbestosAndEnvironmentalUnderwritingLosses	17400000	USD
CY2019	argo	Asbestos And Environmental Underwriting Losses AsbestosAndEnvironmentalUnderwritingLosses	8300000	USD
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CY2021Q4	us-gaap	Senior Notes SeniorNotes	140300000	USD
CY2020Q4	us-gaap	Senior Notes SeniorNotes	140200000	USD
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CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	43100000	USD
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CY2021	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	0	shares
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CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	12800000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	50100000	USD
CY2021	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-73300000	USD
CY2021	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	8000000.0	USD
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CY2021	us-gaap	Net Income Loss NetIncomeLoss	6700000	USD
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CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	10500000	USD
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CY2021Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	10600000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	9600000	USD
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$ARGD
Argo Group International Holdings, Inc. Stock $argd

2021 Q4 Form 10-K Financial Statement

#000162828022006331 Filed on March 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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

2021 Q4 Form 10-K Financial Statement

#000162828022006331 Filed on March 16, 2022

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

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