$ACGL
ARCH CAPITAL GROUP LTD. Stock $acgl

$acgl Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000094748423000015 Filed on February 24, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$3.120B	$3.032B	$9.615B
YoY Change	60.67%	34.98%	3.94%
Cost Of Revenue	$1.471B		$5.028B
YoY Change	46.98%		9.66%
Gross Profit	$1.649B		$4.587B
YoY Change	75.24%		-1.67%
Gross Profit Margin	52.85%		47.71%
Selling, General & Admin	$30.00M	$17.82M	$95.48M
YoY Change	-7.21%	-1.82%	20.62%
% of Gross Profit	1.82%		2.08%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$23.00M	$25.72M	$1.740B
YoY Change	-93.92%	-22.37%	33.49%
% of Gross Profit	1.39%		37.92%
Operating Expenses	$2.376B	$2.071B	$8.097B
YoY Change	37.47%	24.3%	14.87%
Operating Profit	-$727.0M		-$3.510B
YoY Change	-7.68%		47.25%
Interest Expense	-$2.000M	-$72.57M	$130.3M
YoY Change	-106.11%	-290.75%	-6.6%
% of Operating Profit
Other Income/Expense, Net	$319.0M		$1.128B
YoY Change	10.02%		12.98%
Pretax Income	$742.0M	$887.5M	$1.562B
YoY Change	302.1%	43.74%	-34.02%
Income Tax	$64.00M	$60.92M	$79.96M
% Of Pretax Income	8.63%	6.86%	5.12%
Net Earnings	$705.0M	$849.5M	$1.477B
YoY Change	260.06%	36.3%	-31.52%
Net Earnings / Revenue	22.6%	28.02%	15.36%
Basic Earnings Per Share	$1.92		$3.90
Diluted Earnings Per Share	$1.87	$2.26	$3.80
COMMON SHARES
Basic Shares Outstanding	371.2M shares	369.9M shares	368.6M shares
Diluted Shares Outstanding	377.6M shares		377.6M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$803.0M	$855.1M
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		$123.1M	$123.1M
YoY Change		15.21%	15.21%
Goodwill		$342.1M
YoY Change		-0.81%
Intangibles
YoY Change
Long-Term Investments	$3.896B	$3.774B	$28.26B
YoY Change	17.15%	22.64%	1.93%
Other Assets	$412.0M	$418.2M	$418.2M
YoY Change	-18.12%	-8.31%	-8.31%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$51.10B	$47.99B	$47.99B
YoY Change	11.88%	6.41%	6.41%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses		$151.9M	$151.9M
YoY Change		19.87%	19.87%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$262.0M	$246.9M	$246.9M
YoY Change	48.48%	28.9%	28.9%
LONG-TERM LIABILITIES
Long-Term Debt	$2.726B	$2.725B	$2.725B
YoY Change	0.05%	0.04%	0.04%
Other Long-Term Liabilities	$1.569B	$1.464B	$1.464B
YoY Change	-6.37%	1.32%	1.32%
Total Long-Term Liabilities	$4.295B	$4.190B	$4.190B
YoY Change	-2.4%	0.48%	0.48%
TOTAL LIABILITIES
Total Short-Term Liabilities	$262.0M	$246.9M	$246.9M
Total Long-Term Liabilities	$4.295B	$4.190B	$4.190B
Total Liabilities	$37.10B	$35.07B	$35.08B
YoY Change	13.3%	11.17%	11.17%
SHAREHOLDERS EQUITY
Retained Earnings	$16.60B	$15.89B
YoY Change	13.36%	9.94%
Common Stock	$2.261B	$2.212B
YoY Change	5.91%	6.06%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$4.403B	$4.400B
YoY Change	9.06%	16.99%
Treasury Stock Shares		217.9M shares
Shareholders Equity	$13.99B	$12.91B	$12.91B
YoY Change
Total Liabilities & Shareholders Equity	$51.10B	$47.99B	$47.99B
YoY Change	11.88%	6.41%	6.41%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	$705.0M	$849.5M	$1.477B
YoY Change	260.06%	36.3%	-31.52%
Depreciation, Depletion And Amortization	$23.00M	$25.72M	$1.740B
YoY Change	-93.92%	-22.37%	33.49%
Cash From Operating Activities	$963.0M	$981.5M	$3.815B
YoY Change	74.59%	22.69%	11.31%
INVESTING ACTIVITIES
Capital Expenditures	$11.00M	$13.29M	$51.67M
YoY Change	-193.46%	-290.2%	-224.83%
Acquisitions			$0.00
YoY Change
Other Investing Activities	-$985.0M	-$982.0M	-$125.4M
YoY Change	178990.91%	44.53%	-123.94%
Cash From Investing Activities	-$996.0M	-$995.3M	-$3.102B
YoY Change	218.5%	45.0%	44.97%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$585.8M
YoY Change			-52.54%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-30.00M	-1.849M	-$705.7M
YoY Change	-87.16%	-99.47%	-42.6%
NET CHANGE
Cash From Operating Activities	963.0M	981.5M	$3.815B
Cash From Investing Activities	-996.0M	-995.3M	-$3.102B
Cash From Financing Activities	-30.00M	-1.849M	-$705.7M
Net Change In Cash	-63.00M	-15.67M	-$41.44M
YoY Change	-4777.06%	-93.31%	-271.06%
FREE CASH FLOW
Cash From Operating Activities	$963.0M	$981.5M	$3.815B
Capital Expenditures	$11.00M	$13.29M	$51.67M
Free Cash Flow	$952.0M	$968.2M	$3.764B
YoY Change	68.99%	19.98%	8.49%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022	dei	Entity Central Index Key EntityCentralIndexKey	0000947484
CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
CY2022	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2022	dei	Amendment Flag AmendmentFlag	false
CY2020	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	http://fasb.org/us-gaap/2022#AccountingStandardsUpdate201613Member
CY2022	acgl	Equity Method Investments Time Lag For Reporting Low Endof Range EquityMethodInvestmentsTimeLagForReportingLowEndofRange	P1M
CY2022	acgl	Equity Method Investments Time Lag For Reporting High Endof Range EquityMethodInvestmentsTimeLagForReportingHighEndofRange	P3M
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P3Y0M
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Requisite Service Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardRequisiteServicePeriod1	P3Y0M
CY2022	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2022#MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments
CY2022	acgl	Equity Method Investments Time Lag For Reporting Low Endof Range EquityMethodInvestmentsTimeLagForReportingLowEndofRange	P1M
CY2022	acgl	Equity Method Investments Time Lag For Reporting High Endof Range EquityMethodInvestmentsTimeLagForReportingHighEndofRange	P3M
CY2022	acgl	Equity Method Investments Time Lag For Reporting High Endof Range EquityMethodInvestmentsTimeLagForReportingHighEndofRange	P3M
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssets
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssets
CY2021Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilities
CY2022Q4	us-gaap	Operating Lease Liability Statement Of Financial Position Extensible List OperatingLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilities
CY2022	dei	Document Type DocumentType	10-K
CY2022	dei	Document Annual Report DocumentAnnualReport	true
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022	dei	Entity File Number EntityFileNumber	001-16209
CY2022	dei	Entity Registrant Name EntityRegistrantName	ARCH CAPITAL GROUP LTD.
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	D0
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	98-0374481
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	Waterloo House, Ground Floor
CY2022	dei	Entity Address Address Line2 EntityAddressAddressLine2	100 Pitts Bay Road,
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	Pembroke
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	HM 08,
CY2022	dei	Entity Address Country EntityAddressCountry	BM
CY2022	dei	City Area Code CityAreaCode	(441)
CY2022	dei	Local Phone Number LocalPhoneNumber	278-9250
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2022	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2022	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2022	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2022	dei	Entity Small Business EntitySmallBusiness	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2022	dei	Entity Shell Company EntityShellCompany	false
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CY2022	dei	Auditor Firm AuditorFirmId	238
CY2022	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2022	dei	Auditor Location AuditorLocation	New York, New York
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CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	21544000	usd
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CY2021	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	79157000	usd
CY2020	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	81988000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	106200000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	82955000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	69031000	usd
CY2022	us-gaap	Interest Expense InterestExpense	130266000	usd
CY2021	us-gaap	Interest Expense InterestExpense	139470000	usd
CY2020	us-gaap	Interest Expense InterestExpense	143456000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	100905000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	41529000	usd
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-83634000	usd
CY2022	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	8126315000	usd
CY2021	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	7146629000	usd
CY2020	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	6947726000	usd
CY2022	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	1488493000	usd
CY2021	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	2103351000	usd
CY2020	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	1560783000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	201216000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	295533000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	197662000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-121255000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-166951000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-85824000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79961000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	128582000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	111838000	usd
CY2022	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	73891000	usd
CY2021	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	264693000	usd
CY2020	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	16766000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1482423000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	2239462000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	1465711000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5490000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	82613000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	60190000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1476933000	usd
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.32
CY2021	us-gaap	Net Income Loss NetIncomeLoss	2156849000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	1405521000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	40736000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	48343000	usd
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41612000	usd
CY2022	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	0	usd
CY2021	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	15101000	usd
CY2020	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	0	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1436197000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2093405000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1363909000	usd
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.90
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.34
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.80
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.23
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	368612197	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	391748715	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	403062179	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	377609767	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	400345936	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	410259455	shares
CY2022	us-gaap	Profit Loss ProfitLoss	1482423000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	2239462000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	1465711000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1772649000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-386929000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	678717000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	-247799000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	116068000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesNetOfTax	426187000	usd
CY2022	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-56720000	usd
CY2021	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	-64482000	usd
CY2020	us-gaap	Other Comprehensive Income Foreign Currency Transaction And Translation Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossArisingDuringPeriodNetOfTax	33336000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-99147000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1671983000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1751577000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5490000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	82613000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	60190000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	-13984000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Noncontrolling Interest OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToNoncontrollingInterest	9062000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-104637000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1603354000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1682325000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	12910073000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	13545896000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	13105886000	usd
CY2022Q4	us-gaap	Minority Interest MinorityInterest	0	usd
CY2021Q4	us-gaap	Minority Interest MinorityInterest	0	usd
CY2020Q4	us-gaap	Minority Interest MinorityInterest	823007000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	12910073000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	13545896000	usd
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	13928893000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1482423000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	2239462000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	1465711000	usd
CY2022	acgl	Net Realized Gains Losses NetRealizedGainsLosses	-651568000	usd
CY2021	acgl	Net Realized Gains Losses NetRealizedGainsLosses	427367000	usd
CY2020	acgl	Net Realized Gains Losses NetRealizedGainsLosses	844625000	usd
CY2022	acgl	Equity In Net Income Loss Of Investment Funds Accounted For Using Equity Method And Other Income Loss EquityInNetIncomeLossOfInvestmentFundsAccountedForUsingEquityMethodAndOtherIncomeLoss	-153157000	usd
CY2021	acgl	Equity In Net Income Loss Of Investment Funds Accounted For Using Equity Method And Other Income Loss EquityInNetIncomeLossOfInvestmentFundsAccountedForUsingEquityMethodAndOtherIncomeLoss	464050000	usd
CY2020	acgl	Equity In Net Income Loss Of Investment Funds Accounted For Using Equity Method And Other Income Loss EquityInNetIncomeLossOfInvestmentFundsAccountedForUsingEquityMethodAndOtherIncomeLoss	47951000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	106200000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	82955000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	69031000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	87628000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	87094000	usd
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	71262000	usd
CY2022	acgl	Increase Decrease In Loss And Loss Adjustment Expenses Net Of Recoverables IncreaseDecreaseInLossAndLossAdjustmentExpensesNetOfRecoverables	1889015000	usd
CY2021	acgl	Increase Decrease In Loss And Loss Adjustment Expenses Net Of Recoverables IncreaseDecreaseInLossAndLossAdjustmentExpensesNetOfRecoverables	1762190000	usd
CY2020	acgl	Increase Decrease In Loss And Loss Adjustment Expenses Net Of Recoverables IncreaseDecreaseInLossAndLossAdjustmentExpensesNetOfRecoverables	2113827000	usd
CY2022	acgl	Increase Decrease In Unearned Premiums Net Of Prepaid Reinsurance Premiums IncreaseDecreaseInUnearnedPremiumsNetOfPrepaidReinsurancePremiums	1399112000	usd
CY2021	acgl	Increase Decrease In Unearned Premiums Net Of Prepaid Reinsurance Premiums IncreaseDecreaseInUnearnedPremiumsNetOfPrepaidReinsurancePremiums	936039000	usd
CY2020	acgl	Increase Decrease In Unearned Premiums Net Of Prepaid Reinsurance Premiums IncreaseDecreaseInUnearnedPremiumsNetOfPrepaidReinsurancePremiums	445781000	usd
CY2022	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	1109229000	usd
CY2021	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	685214000	usd
CY2020	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	318643000	usd
CY2022	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	374067000	usd
CY2021	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	263243000	usd
CY2020	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	143948000	usd
CY2022	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	-35509000	usd
CY2021	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	500065000	usd
CY2020	us-gaap	Increase Decrease In Reinsurance Payables IncreaseDecreaseInReinsurancePayables	65950000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	435071000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	340376000	usd
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-10110000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3815227000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	3427555000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2886505000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	16390475000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	35451858000	usd
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	39765277000	usd
CY2022	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	796998000	usd
CY2021	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	1175480000	usd
CY2020	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	1595010000	usd
CY2022	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	1720457000	usd
CY2021	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	1859096000	usd
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	1808727000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	11844004000	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	33577445000	usd
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	37949346000	usd
CY2022	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	1554116000	usd
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	918145000	usd
CY2020	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	1147264000	usd
CY2022	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	1221072000	usd
CY2021	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	1765533000	usd
CY2020	us-gaap	Proceeds From Sale Of Other Investments ProceedsFromSaleOfOtherInvestments	1029578000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	714519000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	1628755000	usd
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	871134000	usd
CY2022	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	68818000	usd
CY2021	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	40072000	usd
CY2020	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-179006000	usd
CY2022	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-467249000	usd
CY2021	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-165272000	usd
CY2020	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	1029681000	usd
CY2022	us-gaap	Increase Decrease In Cash Collateral For Borrowed Securities IncreaseDecreaseInCashCollateralForBorrowedSecurities	0	usd
CY2021	us-gaap	Increase Decrease In Cash Collateral For Borrowed Securities IncreaseDecreaseInCashCollateralForBorrowedSecurities	0	usd
CY2020	us-gaap	Increase Decrease In Cash Collateral For Borrowed Securities IncreaseDecreaseInCashCollateralForBorrowedSecurities	-81210000	usd
CY2022	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	0	usd
CY2021	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	753916000	usd
CY2020	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	0	usd
CY2022	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	usd
CY2021	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	349202000	usd
CY2020	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	usd
CY2022	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	51672000	usd
CY2021	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	41394000	usd
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	39872000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-125405000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	523864000	usd
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	62197000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-3102055000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2139732000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-3043226000	usd
CY2022	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	usd
CY2021	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	485821000	usd
CY2020	us-gaap	Proceeds From Issuance Of Preferred Stock And Preference Stock ProceedsFromIssuanceOfPreferredStockAndPreferenceStock	0	usd
CY2022	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	usd
CY2021	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	450000000	usd
CY2020	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	585823000	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1234294000	usd
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	83472000	usd
CY2022	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	6660000	usd
CY2021	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	6418000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-85827000	usd
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	1876000	usd
CY2022	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	usd
CY2021	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	0	usd
CY2020	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1018793000	usd
CY2022	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	usd
CY2021	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	0	usd
CY2020	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	359000000	usd
CY2022	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	0	usd
CY2021	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	0	usd
CY2020	us-gaap	Increase Decrease In Cash Collateral For Loaned Securities IncreaseDecreaseInCashCollateralForLoanedSecurities	-81210000	usd
CY2022	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	0	usd
CY2021	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	15971000	usd
CY2020	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-2867000	usd
CY2022	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	0	usd
CY2021	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	1907000	usd
CY2020	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	4945000	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-3278000	usd
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	73715000	usd
CY2022	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	40736000	usd
CY2021	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	48280000	usd
CY2020	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	41612000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-705726000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1229549000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	521278000	usd
CY2022	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-48889000	usd
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-34047000	usd
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	22289000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-41443000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	24227000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	386846000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1314771000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1290544000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	903698000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1273328000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1314771000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1290544000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	254922000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	286810000	usd
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	202940000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	128425000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	139301000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	133491000	usd
CY2022	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:10pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates and assumptions. The Company’s principal estimates include:</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The reserve for losses and loss adjustment expenses;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">Reinsurance recoverable on unpaid and paid losses and loss adjustment expenses, including the provision for uncollectible amounts;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">Estimates of written and earned premiums;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The valuation of the investment portfolio and assessment of allowance for credit losses;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The valuation of purchased intangible assets;</span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The assessment of goodwill and intangible assets for impairment; and</span></div><div style="margin-bottom:10pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;padding-left:14.5pt">The valuation of deferred tax assets.</span></div>
CY2022	acgl	Premium Revenue Recognition Period PremiumRevenueRecognitionPeriod	P12M
CY2022	us-gaap	Derivatives Methods Of Accounting Nonhedging Derivatives DerivativesMethodsOfAccountingNonhedgingDerivatives	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company recognizes all derivative instruments, including embedded derivative instruments, at fair value in its consolidated balance sheets. The Company employs the use of derivative instruments within its operations to mitigate risks arising from assets and liabilities held in foreign currencies as well as part of its overall investment strategy. For such instruments, changes in assets and liabilities measured at fair value are recorded as “Net realized gains (losses)” in the consolidated statements of income. In addition, the Company’s derivative instruments include amounts related to underwriting activities where an insurance or reinsurance contract meets the accounting definition of a derivative instrument. For such contracts, changes in fair value are reflected in “Other underwriting income” in the consolidated statements of income as the underlying contract originates from the Company’s underwriting operations. For the periods ended 2022, 2021, and 2020, the Company did not designate any derivative instruments as hedges under the relevant accounting guidance. See </span><span style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="#i00be03d4520d45dcbeeb6c59c24a8334_172" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;text-decoration:underline">note 11, “Derivative Instruments”</a></span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> for additional information.</span>
CY2022	us-gaap	Premiums Written Gross PremiumsWrittenGross	15326447000	usd
CY2022	us-gaap	Ceded Premiums Written CededPremiumsWritten	4249258000	usd
CY2022	us-gaap	Premiums Written Net PremiumsWrittenNet	11077189000	usd
CY2022	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	-1399112000	usd
CY2022	us-gaap	Premiums Earned Net PremiumsEarnedNet	9678077000	usd
CY2022	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	13227000	usd
CY2022	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	5027517000	usd
CY2022	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1739580000	usd
CY2022	us-gaap	Other Expenses OtherExpenses	1128175000	usd
CY2022	acgl	Underwriting Income Loss Segment UnderwritingIncomeLossSegment	1796032000	usd
CY2022	us-gaap	Investment Income Net InvestmentIncomeNet	496547000	usd
CY2022	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	-662734000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	115856000	usd
CY2022	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-26165000	usd
CY2022	acgl	Segment Other Cost And Expense Operating SegmentOtherCostAndExpenseOperating	94390000	usd
CY2022	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	1092000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	106200000	usd
CY2022	us-gaap	Interest Expense InterestExpense	130266000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	100905000	usd
CY2022	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	1488493000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79961000	usd
CY2022	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	73891000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1482423000	usd
CY2022	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	5490000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1476933000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	40736000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1436197000	usd
CY2022	us-gaap	Loss Ratio LossRatio	0.519
CY2022	acgl	Acquisition Expense Ratio Percentage AcquisitionExpenseRatioPercentage	0.180
CY2022	acgl	Other Operating Expense Ratio Percentage OtherOperatingExpenseRatioPercentage	0.117
CY2022	acgl	Combined Ratio Percentage CombinedRatioPercentage	0.816
CY2022Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	804289000	usd
CY2022Q4	acgl	Investable Assets InvestableAssets	28065497000	usd
CY2022Q4	us-gaap	Assets Assets	47990507000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	35069605000	usd
CY2021	us-gaap	Premiums Written Gross PremiumsWrittenGross	12752487000	usd
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	3734150000	usd
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	9018337000	usd
CY2021	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	-936039000	usd
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	8082298000	usd
CY2021	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	22073000	usd
CY2021	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4584803000	usd
CY2021	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1303178000	usd
CY2021	us-gaap	Other Expenses OtherExpenses	998595000	usd
CY2021	acgl	Underwriting Income Loss Segment UnderwritingIncomeLossSegment	1217795000	usd
CY2021	us-gaap	Investment Income Net InvestmentIncomeNet	389118000	usd
CY2021	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	379845000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	366402000	usd
CY2021	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	10244000	usd
CY2021	acgl	Segment Other Cost And Expense Operating SegmentOtherCostAndExpenseOperating	77119000	usd
CY2021	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	2038000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	82955000	usd
CY2021	us-gaap	Interest Expense InterestExpense	139470000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	41529000	usd
CY2021	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	2103351000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	128582000	usd
CY2021	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	264693000	usd
CY2020	us-gaap	Premiums Written Gross PremiumsWrittenGross	10088068000	usd
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	2650352000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	2239462000	usd
CY2021	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	4299000	usd
CY2021	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	78314000	usd
CY2021	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	78314000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	2156849000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	48343000	usd
CY2021	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	15101000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2093405000	usd
CY2021	us-gaap	Loss Ratio LossRatio	0.567
CY2021	acgl	Acquisition Expense Ratio Percentage AcquisitionExpenseRatioPercentage	0.161
CY2021	acgl	Other Operating Expense Ratio Percentage OtherOperatingExpenseRatioPercentage	0.124
CY2021	acgl	Combined Ratio Percentage CombinedRatioPercentage	0.852
CY2021Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	944983000	usd
CY2021Q4	acgl	Investable Assets InvestableAssets	27442153000	usd
CY2021Q4	us-gaap	Assets Assets	45100945000	usd
CY2021Q4	us-gaap	Liabilities Liabilities	31545816000	usd
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	7437716000	usd
CY2020	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	-445781000	usd
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	6991935000	usd
CY2020	us-gaap	Insurance Commissions And Fees InsuranceCommissionsAndFees	26784000	usd
CY2020	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4689599000	usd
CY2020	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	1004842000	usd
CY2020	us-gaap	Other Expenses OtherExpenses	875176000	usd
CY2020	acgl	Underwriting Income Loss Segment UnderwritingIncomeLossSegment	449102000	usd
CY2020	us-gaap	Investment Income Net InvestmentIncomeNet	519608000	usd
CY2020	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	823460000	usd
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	146693000	usd
CY2020	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	29000	usd
CY2020	acgl	Segment Other Cost And Expense Operating SegmentOtherCostAndExpenseOperating	68492000	usd
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	13496000	usd
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	69031000	usd
CY2020	us-gaap	Interest Expense InterestExpense	143456000	usd
CY2020	us-gaap	Foreign Currency Transaction Gain Loss Before Tax ForeignCurrencyTransactionGainLossBeforeTax	-83634000	usd
CY2020	acgl	Income Loss From Continuing Operations Before Earnings From Affiliates Income Taxes Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeEarningsFromAffiliatesIncomeTaxesNoncontrollingInterest	1560783000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	111838000	usd
CY2020	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	16766000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	1465711000	usd
CY2020	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	7114000	usd
CY2020	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	53076000	usd
CY2020	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	53076000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	1405521000	usd
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41612000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1363909000	usd
CY2020	us-gaap	Loss Ratio LossRatio	0.671
CY2020	acgl	Acquisition Expense Ratio Percentage AcquisitionExpenseRatioPercentage	0.144
CY2020	acgl	Other Operating Expense Ratio Percentage OtherOperatingExpenseRatioPercentage	0.125
CY2020	acgl	Combined Ratio Percentage CombinedRatioPercentage	0.940
CY2020Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	692863000	usd
CY2020Q4	acgl	Investable Assets InvestableAssets	29513907000	usd
CY2020Q4	us-gaap	Assets Assets	43282297000	usd
CY2020Q4	us-gaap	Liabilities Liabilities	29294856000	usd
CY2022	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-bottom:10pt;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 represents an analysis of losses and loss adjustment expenses and a reconciliation of the beginning and ending reserve for losses and loss adjustment expenses:</span></div><div style="margin-bottom:10pt;margin-top:5pt;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:61.034%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.034%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.034%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.530%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.038%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="15" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;padding-right:4.5pt;text-align:center"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">Year Ended December 31,</span></div></td></tr><tr><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="border-top:1pt solid #000000;padding:2px 3.25pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">2022</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 3.25pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.5pt;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 3.25pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:7.5pt;font-weight:700;line-height:100%">2020</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reserve for losses and loss adjustment expenses at beginning of 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:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,757,156 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</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:8pt;font-weight:400;line-height:100%">16,513,929 </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:8pt;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:8pt;font-weight:400;line-height:100%">13,891,842 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Unpaid losses and loss adjustment expenses recoverable</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:8pt;font-weight:400;line-height:100%">5,599,231 </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:8pt;font-weight:400;line-height:100%">4,314,855 </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:8pt;font-weight:400;line-height:100%">4,082,650 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;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%">Net reserve for losses and loss adjustment expenses at beginning of year</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:8pt;font-weight:400;line-height:100%">12,157,925 </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:8pt;font-weight:400;line-height:100%">12,199,074 </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:8pt;font-weight:400;line-height:100%">9,809,192 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net incurred losses and loss adjustment expenses relating to losses occurring in:</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"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;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%">Current 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:8pt;font-weight:400;line-height:100%">5,798,528 </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:8pt;font-weight:400;line-height:100%">4,940,987 </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:8pt;font-weight:400;line-height:100%">4,851,051 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;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%">Prior 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:8pt;font-weight:400;line-height:100%">(771,011)</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:8pt;font-weight:400;line-height:100%">(356,184)</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:8pt;font-weight:400;line-height:100%">(161,452)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 12.25pt;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%">Total net incurred losses and loss adjustment expenses</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:8pt;font-weight:400;line-height:100%">5,027,517 </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:8pt;font-weight:400;line-height:100%">4,584,803 </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:8pt;font-weight:400;line-height:100%">4,689,599 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net losses and loss adjustment expense reserves of acquired business (1)</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:8pt;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:8pt;font-weight:400;line-height:100%">104,176 </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:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Retroactive reinsurance transactions (2)</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:8pt;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:8pt;font-weight:400;line-height:100%">(444,147)</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:8pt;font-weight:400;line-height:100%">182,210 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Impact of deconsolidation of Somers (3)</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:8pt;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:8pt;font-weight:400;line-height:100%">(1,460,611)</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:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Foreign exchange (gains) losses and other</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:8pt;font-weight:400;line-height:100%">(290,376)</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:8pt;font-weight:400;line-height:100%">1,181 </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:8pt;font-weight:400;line-height:100%">179,190 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#cceeff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net paid losses and loss adjustment expenses relating to losses occurring in:</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"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;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%">Current 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:8pt;font-weight:400;line-height:100%">(887,464)</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:8pt;font-weight:400;line-height:100%">(734,846)</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:8pt;font-weight:400;line-height:100%">(661,529)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7.75pt;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%">Prior 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:8pt;font-weight:400;line-height:100%">(2,254,484)</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:8pt;font-weight:400;line-height:100%">(2,091,705)</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:8pt;font-weight:400;line-height:100%">(1,999,588)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 12.25pt;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%">Total net paid losses and loss adjustment expenses</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:8pt;font-weight:400;line-height:100%">(3,141,948)</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:8pt;font-weight:400;line-height:100%">(2,826,551)</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:8pt;font-weight:400;line-height:100%">(2,661,117)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr style="height:11pt"><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="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Net reserve for losses and loss adjustment expenses at end of 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:8pt;font-weight:400;line-height:100%">13,753,118 </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:8pt;font-weight:400;line-height:100%">12,157,925 </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:8pt;font-weight:400;line-height:100%">12,199,074 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Unpaid losses and loss adjustment expenses recoverable</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:8pt;font-weight:400;line-height:100%">6,278,825 </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:8pt;font-weight:400;line-height:100%">5,599,231 </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:8pt;font-weight:400;line-height:100%">4,314,855 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7.75pt;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%">Reserve for losses and loss adjustment expenses at end of year</span></td><td style="background-color:#cceeff;border-bottom:2pt solid #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:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:2pt solid #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:8pt;font-weight:400;line-height:100%">20,031,943 </span></td><td style="background-color:#cceeff;border-bottom:2pt solid #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:2pt solid #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:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:2pt solid #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">17,757,156 </span></td><td style="background-color:#cceeff;border-bottom:2pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:2pt solid #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:2pt solid #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:8pt;font-weight:400;line-height:100%">16,513,929 </span></td><td style="background-color:#cceeff;border-bottom:2pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="padding-left:22.5pt;text-indent:-22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(1) Represents activity related to the Company’s acquisitions in the 2021 period. See</span><span style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"> </a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">note 2</a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">, </a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">“</a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">Acquisitions</a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">.</a><a href="#i00be03d4520d45dcbeeb6c59c24a8334_145" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">”</a></span></div><div style="padding-left:22.5pt;text-indent:-22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(2) See ‘Retroactive Reinsurance Transactions’ section.</span></div><div style="margin-bottom:10pt;padding-left:22.5pt;text-indent:-22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(3) See </span><span style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline"><a href="#i00be03d4520d45dcbeeb6c59c24a8334_175" style="color:#0000ff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;text-decoration:underline">note 12, “Variable Interest Entity and Noncontrolling Interests.”</a></span></div>
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	17757156000	usd
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	16513929000	usd
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	13891842000	usd
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	5599231000	usd
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	4314855000	usd
CY2019Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	4082650000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	12157925000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	12199074000	usd
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	9809192000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	5798528000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	4940987000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	4851051000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-771011000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-356184000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-161452000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	5027517000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	4584803000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	4689599000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	0	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	104176000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Business Acquisitions LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseBusinessAcquisitions	0	usd
CY2022	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Retroactive Reinsurance LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsRetroactiveReinsurance	0	usd
CY2021	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Retroactive Reinsurance LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsRetroactiveReinsurance	444147000	usd
CY2020	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims Retroactive Reinsurance LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaimsRetroactiveReinsurance	-182210000	usd
CY2022	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Impact Of Deconsolidation LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseImpactOfDeconsolidation	0	usd
CY2021	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Impact Of Deconsolidation LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseImpactOfDeconsolidation	1460611000	usd
CY2020	acgl	Liability For Unpaid Claims And Claims Adjustment Expense Impact Of Deconsolidation LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseImpactOfDeconsolidation	0	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	-290376000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	1181000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss	179190000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	887464000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	734846000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	661529000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	2254484000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	2091705000	usd
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	1999588000	usd
CY2022	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	3141948000	usd
CY2021	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2826551000	usd
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2661117000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	13753118000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	12157925000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	12199074000	usd
CY2022Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	6278825000	usd
CY2021Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	5599231000	usd
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	4314855000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	20031943000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	17757156000	usd
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	16513929000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-771000000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-356200000	usd
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-161500000	usd
CY2022Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	13445271000	usd
CY2022Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claim Adjustment Expense Other Reconciling Item ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseOtherReconcilingItem	102283000	usd
CY2021	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	2177000	usd
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	2633280000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	39958000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	11400000	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	3800000	usd
CY2022Q4	us-gaap	Shortduration Insurance Contracts Discounted Liabilities Aggregate Discount ShortdurationInsuranceContractsDiscountedLiabilitiesAggregateDiscount	60536000	usd
CY2022Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claims Adjustment Expense Accumulated Unallocated Claim Adjustment Expense ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense	266100000	usd
CY2022Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claim Adjustment Expense Aggregate Reconciling Items ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseAggregateReconcilingItems	307847000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	20031943000	usd
CY2021Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	2633280000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	39958000	usd
CY2022	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-4556000	usd
CY2022Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	3624777000	usd
CY2022Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	35402000	usd
CY2020Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	2064586000	usd
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	37781000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	5880735000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	13230000	usd
CY2022	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	8314000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	6563654000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	21544000	usd
CY2020Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	4500802000	usd
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	11636000	usd
CY2021	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	1594000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	5880735000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	13230000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	6563654000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	5880735000	usd
CY2021Q4	acgl	Contractholder Deductibles Receivable ContractholderDeductiblesReceivable	1828691000	usd
CY2021Q4	acgl	Contractholder Receivables Allowance For Credit Loss ContractholderReceivablesAllowanceForCreditLoss	3437000	usd
CY2022	acgl	Contractholder Receivables Credit Loss Expense Reversal ContractholderReceivablesCreditLossExpenseReversal	-746000	usd
CY2022Q4	acgl	Contractholder Deductibles Receivable ContractholderDeductiblesReceivable	1731293000	usd
CY2022Q4	acgl	Contractholder Receivables Allowance For Credit Loss ContractholderReceivablesAllowanceForCreditLoss	2691000	usd
CY2020Q4	acgl	Contractholder Deductibles Receivable ContractholderDeductiblesReceivable	1986924000	usd
CY2020Q4	acgl	Contractholder Receivables Allowance For Credit Loss ContractholderReceivablesAllowanceForCreditLoss	8638000	usd
CY2021	acgl	Contractholder Receivables Credit Loss Expense Reversal ContractholderReceivablesCreditLossExpenseReversal	-5201000	usd
CY2021Q4	acgl	Contractholder Deductibles Receivable ContractholderDeductiblesReceivable	1828691000	usd
CY2021Q4	acgl	Contractholder Receivables Allowance For Credit Loss ContractholderReceivablesAllowanceForCreditLoss	3437000	usd
CY2022	us-gaap	Direct Premiums Written DirectPremiumsWritten	8540787000	usd
CY2021	us-gaap	Direct Premiums Written DirectPremiumsWritten	7706832000	usd
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	6553910000	usd
CY2022	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	6785660000	usd
CY2021	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	5045655000	usd
CY2020	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	3534158000	usd
CY2022	us-gaap	Ceded Premiums Written CededPremiumsWritten	4249258000	usd
CY2021	us-gaap	Ceded Premiums Written CededPremiumsWritten	3734150000	usd
CY2020	us-gaap	Ceded Premiums Written CededPremiumsWritten	2650352000	usd
CY2022	us-gaap	Premiums Written Net PremiumsWrittenNet	11077189000	usd
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	9018337000	usd
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	7437716000	usd
CY2022	us-gaap	Direct Premiums Earned DirectPremiumsEarned	8057635000	usd
CY2021	us-gaap	Direct Premiums Earned DirectPremiumsEarned	7149794000	usd
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	6361451000	usd
CY2022	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	5767738000	usd
CY2021	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	4333873000	usd
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	3213873000	usd
CY2022	us-gaap	Ceded Premiums Earned CededPremiumsEarned	4147296000	usd
CY2021	us-gaap	Ceded Premiums Earned CededPremiumsEarned	3401369000	usd
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	2583389000	usd
CY2022	us-gaap	Premiums Earned Net PremiumsEarnedNet	9678077000	usd
CY2021	us-gaap	Premiums Earned Net PremiumsEarnedNet	8082298000	usd
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	6991935000	usd
CY2022	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	3990768000	usd
CY2021	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	4266758000	usd
CY2020	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	4392392000	usd
CY2022	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	3559133000	usd
CY2021	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	2826820000	usd
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	2204323000	usd
CY2022	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2522384000	usd
CY2021	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2508775000	usd
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	1907116000	usd
CY2022	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	5027517000	usd
CY2021	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4584803000	usd
CY2020	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	4689599000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	21014451000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	89234000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1648287000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	41355000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	22614859000	usd
CY2021Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	19732825000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	198691000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	171544000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	2883000	usd
CY2021Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	19708561000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	12975400000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	927531000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	5671580000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	720756000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	18646980000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	1648287000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	12238683000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	157279000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	297357000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	14265000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	12536040000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	171544000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	9810	lots
CY2022Q4	acgl	Available For Sale Securities Qualitative Disclosure Number Of Positions AvailableForSaleSecuritiesQualitativeDisclosureNumberOfPositions	12590	lots
CY2022Q4	acgl	Available For Sale Securities Qualitative Disclosure Largest Single Loss AvailableForSaleSecuritiesQualitativeDisclosureLargestSingleLoss	7200000	usd
CY2021Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	4700	lots
CY2021Q4	acgl	Available For Sale Securities Qualitative Disclosure Number Of Positions AvailableForSaleSecuritiesQualitativeDisclosureNumberOfPositions	10240	lots
CY2021Q4	acgl	Available For Sale Securities Qualitative Disclosure Largest Single Loss AvailableForSaleSecuritiesQualitativeDisclosureLargestSingleLoss	1100000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	860000000	usd
CY2021Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1800000000	usd
CY2022	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	567322000	usd
CY2021	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	477123000	usd
CY2020	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	608823000	usd
CY2022	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	70775000	usd
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	88005000	usd
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	89215000	usd
CY2022	us-gaap	Investment Income Net InvestmentIncomeNet	496547000	usd
CY2021	us-gaap	Investment Income Net InvestmentIncomeNet	389118000	usd
CY2020	us-gaap	Investment Income Net InvestmentIncomeNet	519608000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	81161000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	313886000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	595941000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	317150000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	156791000	usd
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	117282000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	74922000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	122606000	usd
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	26849000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-267927000	usd
CY2021	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	48746000	usd
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	102394000	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecrease	43909000	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecrease	2100000	usd
CY2020	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Period Increase Decrease DebtSecuritiesAvailableForSaleAllowanceForCreditLossPeriodIncreaseDecrease	3597000	usd
CY2022	acgl	Underwriting Related Allowance For Credit Losses Credit Loss Expense Reversal UnderwritingRelatedAllowanceForCreditLossesCreditLossExpenseReversal	13274000	usd
CY2021	acgl	Underwriting Related Allowance For Credit Losses Credit Loss Expense Reversal UnderwritingRelatedAllowanceForCreditLossesCreditLossExpenseReversal	-1062000	usd
CY2020	acgl	Underwriting Related Allowance For Credit Losses Credit Loss Expense Reversal UnderwritingRelatedAllowanceForCreditLossesCreditLossExpenseReversal	10007000	usd
CY2022	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Writeoff DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff	0	usd
CY2021	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Writeoff DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff	0	usd
CY2020	us-gaap	Other Than Temporary Impairment Loss Debt Securities Available For Sale Recognized In Earnings OtherThanTemporaryImpairmentLossDebtSecuritiesAvailableForSaleRecognizedInEarnings	533000	usd
CY2022	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-75023000	usd
CY2021	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-32390000	usd
CY2020	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	179675000	usd
CY2022	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-3553000	usd
CY2021	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-53537000	usd
CY2020	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	3575000	usd
CY2022	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	-662734000	usd
CY2022	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	73900000	usd
CY2021	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	379845000	usd
CY2020	us-gaap	Marketable Securities Gain Loss Excluding Other Than Temporary Impairments MarketableSecuritiesGainLossExcludingOtherThanTemporaryImpairments	823460000	usd
CY2022Q4	us-gaap	Other Investments OtherInvestments	1644197000	usd
CY2021Q4	us-gaap	Other Investments OtherInvestments	1973550000	usd
CY2022Q4	us-gaap	Equity Method Investments EquityMethodInvestments	3774310000	usd
CY2021Q4	us-gaap	Equity Method Investments EquityMethodInvestments	3077611000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	115900000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	366400000	usd
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	146700000	usd
CY2022Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	3904776000	usd
CY2021Q4	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	3248206000	usd
CY2021	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	264700000	usd
CY2020	acgl	Income Loss From Operating Affiliates Equity Method IncomeLossFromOperatingAffiliatesEquityMethod	16800000	usd
CY2022Q4	acgl	Restricted Assets RestrictedAssets	8701480000	usd
CY2021Q4	acgl	Restricted Assets RestrictedAssets	8249732000	usd
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	855118000	usd
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	858668000	usd
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	906448000	usd
CY2022Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	418210000	usd
CY2021Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	456103000	usd
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents RestrictedCashAndCashEquivalents	384096000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1273328000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1314771000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1290544000	usd
CY2022Q4	acgl	Total Assets And Liabilities Measured At Fair Value TotalAssetsAndLiabilitiesMeasuredAtFairValue	23800000000	usd
CY2022Q4	acgl	Total Assets And Liabilities Measured At Fair Value Priced Using Non Binding Broker Quotes TotalAssetsAndLiabilitiesMeasuredAtFairValuePricedUsingNonBindingBrokerQuotes	12600000	usd
CY2022Q4	acgl	Percentage Of Total Assets And Liabilities Measured At Fair Value Priced Using Non Binding Broker Quotes PercentageOfTotalAssetsAndLiabilitiesMeasuredAtFairValuePricedUsingNonBindingBrokerQuotes	0.001
CY2021Q4	acgl	Total Assets And Liabilities Measured At Fair Value TotalAssetsAndLiabilitiesMeasuredAtFairValue	23800000000	usd
CY2021Q4	acgl	Total Assets And Liabilities Measured At Fair Value Priced Using Non Binding Broker Quotes TotalAssetsAndLiabilitiesMeasuredAtFairValuePricedUsingNonBindingBrokerQuotes	7700000	usd
CY2021Q4	acgl	Percentage Of Total Assets And Liabilities Measured At Fair Value Priced Using Non Binding Broker Quotes PercentageOfTotalAssetsAndLiabilitiesMeasuredAtFairValuePricedUsingNonBindingBrokerQuotes	0.000
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	147400000	usd
CY2022Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	73200000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeAssetAmountNotOffsetAgainstCollateral	122300000	usd
CY2021Q4	us-gaap	Derivative Fair Value Of Derivative Liability Amount Not Offset Against Collateral DerivativeFairValueOfDerivativeLiabilityAmountNotOffsetAgainstCollateral	53900000	usd
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	9233000	usd
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	58548000	usd
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	55404000	usd
CY2022	acgl	Redeemable Noncontrolling Interest Decrease From Deconsolidation RedeemableNoncontrollingInterestDecreaseFromDeconsolidation	0	usd
CY2021	acgl	Redeemable Noncontrolling Interest Decrease From Deconsolidation RedeemableNoncontrollingInterestDecreaseFromDeconsolidation	48919000	usd
CY2020	acgl	Redeemable Noncontrolling Interest Decrease From Deconsolidation RedeemableNoncontrollingInterestDecreaseFromDeconsolidation	0	usd
CY2022	acgl	Noncontrolling Interest Period Increase Decrease Other NoncontrollingInterestPeriodIncreaseDecreaseOther	1596000	usd
CY2021	acgl	Noncontrolling Interest Period Increase Decrease Other NoncontrollingInterestPeriodIncreaseDecreaseOther	-396000	usd
CY2020	acgl	Noncontrolling Interest Period Increase Decrease Other NoncontrollingInterestPeriodIncreaseDecreaseOther	3144000	usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	10829000	usd
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	9233000	usd
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	58548000	usd
CY2022	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	0	usd
CY2021	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	78314000	usd
CY2020	us-gaap	Net Income Loss Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossAttributableToNonredeemableNoncontrollingInterest	53076000	usd
CY2022	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	5490000	usd
CY2021	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	4299000	usd
CY2020	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	7114000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5490000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	82613000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	60190000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-64600000	usd
CY2022	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-1829369000	usd
CY2022	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	-247799000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1581570000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-1646170000	usd
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	488895000	usd
CY2021	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	-437427000	usd
CY2021	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	116068000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-553495000	usd
CY2021Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-64600000	usd
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	212091000	usd
CY2020	us-gaap	Oci Before Reclassifications Net Of Tax Attributable To Parent OciBeforeReclassificationsNetOfTaxAttributableToParent	702991000	usd
CY2020	us-gaap	Reclassification From Aoci Current Period Net Of Tax Attributable To Parent ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent	426187000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	276804000	usd
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	488895000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-2010443000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-237794000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1772649000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	-279898000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	-32099000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-247799000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-56554000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	166000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-56720000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-1787099000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-205529000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1581570000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-406774000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-19845000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-386929000	usd
CY2021	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	154996000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	38928000	usd
CY2021	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	116068000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	-64423000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	59000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-64482000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-626193000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-58714000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-567479000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	754572000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	75855000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	678717000	usd
CY2020	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Before Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodBeforeTax	474529000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci For Sale Of Securities Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax	48342000	usd
CY2020	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	426187000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Before Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentBeforeTax	33706000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Translation Adjustment Tax OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax	370000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	33336000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	313749000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	27883000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	285866000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1482423000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	2239462000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	1465711000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	5490000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	82613000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	60190000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1476933000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	2156849000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	1405521000	usd
CY2022	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	40736000	usd
CY2021	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	48343000	usd
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	41612000	usd
CY2022	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	0	usd
CY2021	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	15101000	usd
CY2020	us-gaap	Preferred Stock Redemption Premium PreferredStockRedemptionPremium	0	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1436197000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2093405000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1363909000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	368612197	shares
CY2021	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	391748715	shares
CY2020	us-gaap	Weighted Average Number Of Shares Issued Basic WeightedAverageNumberOfSharesIssuedBasic	403062179	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	2103036	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	1996524	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	1682309	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	6894534	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	6600697	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Call Options And Warrants IncrementalCommonSharesAttributableToCallOptionsAndWarrants	5514967	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	377609767	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	400345936	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	410259455	shares
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.90
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.34
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.80
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.23
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.32
CY2022	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	195588000	usd
CY2021	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	284274000	usd
CY2020	us-gaap	Current Federal State And Local Tax Expense Benefit CurrentFederalStateAndLocalTaxExpenseBenefit	181571000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	5628000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	11259000	usd
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	16091000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	201216000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	295533000	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	197662000	usd
CY2022	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-96599000	usd
CY2021	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-123261000	usd
CY2020	us-gaap	Deferred Federal State And Local Tax Expense Benefit DeferredFederalStateAndLocalTaxExpenseBenefit	-89170000	usd
CY2022	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-24656000	usd
CY2021	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-43690000	usd
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	3346000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-121255000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-166951000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-85824000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79961000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	128582000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	111838000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1562384000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2368042000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	1577549000	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	110337000	usd
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	158269000	usd
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	111947000	usd
CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	12762000	usd
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	23572000	usd
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	1824000	usd
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	10650000	usd
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	20978000	usd
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5027000	usd
CY2022	acgl	Income Tax Reconciliation Dividend Withholding Taxes IncomeTaxReconciliationDividendWithholdingTaxes	10559000	usd
CY2021	acgl	Income Tax Reconciliation Dividend Withholding Taxes IncomeTaxReconciliationDividendWithholdingTaxes	12211000	usd
CY2020	acgl	Income Tax Reconciliation Dividend Withholding Taxes IncomeTaxReconciliationDividendWithholdingTaxes	7105000	usd
CY2022	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-22726000	usd
CY2021	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-40425000	usd
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	13190000	usd
CY2022	us-gaap	Effective Income Tax Rate Reconciliation Beat Amount EffectiveIncomeTaxRateReconciliationBeatAmount	7694000	usd
CY2021	us-gaap	Effective Income Tax Rate Reconciliation Beat Amount EffectiveIncomeTaxRateReconciliationBeatAmount	0	usd
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Beat Amount EffectiveIncomeTaxRateReconciliationBeatAmount	0	usd
CY2022	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-9159000	usd
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-5339000	usd
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-2533000	usd
CY2022	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	9736000	usd
CY2021	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	0	usd
CY2020	us-gaap	Income Tax Reconciliation Tax Credits IncomeTaxReconciliationTaxCredits	0	usd
CY2022	acgl	Effective Income Tax Reconciliation Intercompany Loan Writeoff Amount EffectiveIncomeTaxReconciliationIntercompanyLoanWriteoffAmount	-3544000	usd
CY2021	acgl	Effective Income Tax Reconciliation Intercompany Loan Writeoff Amount EffectiveIncomeTaxReconciliationIntercompanyLoanWriteoffAmount	0	usd
CY2020	acgl	Effective Income Tax Reconciliation Intercompany Loan Writeoff Amount EffectiveIncomeTaxReconciliationIntercompanyLoanWriteoffAmount	-22083000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1352000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	6460000	usd
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	1009000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	79961000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	128582000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	111838000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	76665000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	87960000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	77556000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	72001000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	96581000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	75483000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	55269000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	28062000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	16738000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	20058000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	17365000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	10252000	usd
CY2022Q4	acgl	Deferred Tax Assets Depreciation And Amortization DeferredTaxAssetsDepreciationAndAmortization	141409000	usd
CY2021Q4	acgl	Deferred Tax Assets Depreciation And Amortization DeferredTaxAssetsDepreciationAndAmortization	115041000	usd
CY2022Q4	acgl	Deferred Tax Asset Lease Liability DeferredTaxAssetLeaseLiability	26681000	usd
CY2021Q4	acgl	Deferred Tax Asset Lease Liability DeferredTaxAssetLeaseLiability	21453000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	192949000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Availablefor Sale Securities Gross DeferredTaxAssetsUnrealizedLossesOnAvailableforSaleSecuritiesGross	0	usd
CY2022Q4	acgl	Lloyds Syndicate Uncrystallized Losses Deferred Tax Asset LloydsSyndicateUncrystallizedLossesDeferredTaxAsset	1385000	usd
CY2021Q4	acgl	Lloyds Syndicate Uncrystallized Losses Deferred Tax Asset LloydsSyndicateUncrystallizedLossesDeferredTaxAsset	0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	14450000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Other DeferredTaxAssetsTaxDeferredExpenseOther	703000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	717048000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	431013000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	6968000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	43953000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	710080000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	387060000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	2658000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	1578000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	38905000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssets	70549000	usd
CY2022Q4	acgl	Deferred Tax Liability Lloyds Year Of Account Deferral DeferredTaxLiabilityLloydsYearOfAccountDeferral	0	usd
CY2021Q4	acgl	Deferred Tax Liability Lloyds Year Of Account Deferral DeferredTaxLiabilityLloydsYearOfAccountDeferral	12514000	usd
CY2022Q4	acgl	Deferred Tax Liability Contingency Reserve DeferredTaxLiabilityContingencyReserve	43870000	usd
CY2021Q4	acgl	Deferred Tax Liability Contingency Reserve DeferredTaxLiabilityContingencyReserve	49486000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Other Capitalized Costs DeferredTaxLiabilitiesDeferredExpenseOtherCapitalizedCosts	63708000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Deferred Expense Other Capitalized Costs DeferredTaxLiabilitiesDeferredExpenseOtherCapitalizedCosts	25612000	usd
CY2022Q4	acgl	Deferred Tax Liabilities Investment Related DeferredTaxLiabilitiesInvestmentRelated	9225000	usd
CY2021Q4	acgl	Deferred Tax Liabilities Investment Related DeferredTaxLiabilitiesInvestmentRelated	7492000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	0	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	8377000	usd
CY2021Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	17406000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	20781000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	179147000	usd
CY2021Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	193014000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	530933000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	194046000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	7000000	usd
CY2021Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	44000000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2000000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2008000	usd
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2008000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2022	acgl	Unrecognized Tax Benefits Change Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsChangeResultingFromSettlementsWithTaxingAuthorities	0	usd
CY2021	acgl	Unrecognized Tax Benefits Change Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsChangeResultingFromSettlementsWithTaxingAuthorities	0	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2008000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2008000	usd
CY2022Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	40600000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	33571000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	31691000	usd
CY2022	us-gaap	Sublease Income SubleaseIncome	988000	usd
CY2021	us-gaap	Sublease Income SubleaseIncome	0	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	26051000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	32094000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	42841000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	22686000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	123083000	usd
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	106836000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	151890000	usd
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	126711000	usd
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.042
CY2021Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.039
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P6Y7M6D
CY2021Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y10M24D
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	31861000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	30091000	usd
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Files In Submission

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$ACGL
ARCH CAPITAL GROUP LTD. Stock $acgl

2023 Q1 Form 10-K Financial Statement

#000094748423000015 Filed on February 24, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ACGL ARCH CAPITAL GROUP LTD. Stock $acgl

2023 Q1 Form 10-K Financial Statement

#000094748423000015 Filed on February 24, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ACGL
ARCH CAPITAL GROUP LTD. Stock $acgl