$WRB
BERKLEY W R CORP Stock $wrb

$wrb Overview Financials Valuation SEC Filings Company Website

2024 Q4 Form 10-Q Financial Statement

#000001154424000028 Filed on November 04, 2024

Income Statement

Concept	2024 Q4	2024 Q3
Revenue		$3.400B
YoY Change		12.2%
Cost Of Revenue		$1.826B
YoY Change		11.6%
Gross Profit		$1.574B
YoY Change		12.91%
Gross Profit Margin		46.3%
Selling, General & Admin		$11.23M
YoY Change		-64.18%
% of Gross Profit		0.71%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization
YoY Change
% of Gross Profit
Operating Expenses		$2.894B
YoY Change		11.28%
Operating Profit		-$1.320B
YoY Change		9.4%
Interest Expense		-$31.72M
YoY Change		-199.47%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income		$474.4M
YoY Change		12.98%
Income Tax		$109.1M
% Of Pretax Income		23.0%
Net Earnings		$365.6M
YoY Change		9.61%
Net Earnings / Revenue		10.75%
Basic Earnings Per Share		$0.92
Diluted Earnings Per Share		$0.91
COMMON SHARES
Basic Shares Outstanding	381.1M shares	380.6M shares
Diluted Shares Outstanding		401.8M shares

Balance Sheet

Concept	2024 Q4	2024 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$1.975B	$1.573B
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	$478.5M	$478.4M
YoY Change	12.12%	13.01%
Goodwill	$184.3M	$184.1M
YoY Change	5.58%	5.44%
Intangibles
YoY Change
Long-Term Investments	$1.468B	$1.607B
YoY Change	-9.46%	0.43%
Other Assets		$131.2M
YoY Change		-54.97%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$40.57B	$40.36B
YoY Change	9.05%	11.76%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses		$224.8M
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt		$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities		$224.8M
YoY Change
LONG-TERM LIABILITIES
Long-Term Debt		$2.837B
YoY Change		0.02%
Other Long-Term Liabilities		$1.486B
YoY Change		-3.84%
Total Long-Term Liabilities		$4.323B
YoY Change		-1.34%
TOTAL LIABILITIES
Total Short-Term Liabilities		$224.8M
Total Long-Term Liabilities		$4.323B
Total Liabilities	$32.16B	$31.92B
YoY Change	8.16%	9.38%
SHAREHOLDERS EQUITY
Retained Earnings	$12.27B	$11.91B
YoY Change	11.09%	10.27%
Common Stock	$1.144B	$1.132B
YoY Change	1.78%	1.58%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$4.079B	$4.012B
YoY Change	7.83%	9.12%
Treasury Stock Shares
Shareholders Equity	$8.395B	$8.426B
YoY Change
Total Liabilities & Shareholders Equity	$40.57B	$40.36B
YoY Change	9.05%	11.76%

Cashflow Statement

Concept	2024 Q4	2024 Q3
OPERATING ACTIVITIES
Net Income		$365.6M
YoY Change		9.61%
Depreciation, Depletion And Amortization
YoY Change
Cash From Operating Activities		$1.241B
YoY Change		15.2%
INVESTING ACTIVITIES
Capital Expenditures		$35.41M
YoY Change		44.44%
Acquisitions
YoY Change
Other Investing Activities		-$1.070B
YoY Change		-11.65%
Cash From Investing Activities		-$1.105B
YoY Change		-10.54%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities		-153.8M
YoY Change		573.29%
NET CHANGE
Cash From Operating Activities		1.241B
Cash From Investing Activities		-1.105B
Cash From Financing Activities		-153.8M
Net Change In Cash		-18.17M
YoY Change		-89.97%
FREE CASH FLOW
Cash From Operating Activities		$1.241B
Capital Expenditures		$35.41M
Free Cash Flow		$1.205B
YoY Change		14.52%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2024-09-30
	dei	Entity File Number EntityFileNumber	1-15202
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
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CY2024Q3	us-gaap	Equity Method Investments EquityMethodInvestments	1607381000	usd
CY2024Q3	us-gaap	Real Estate Investments RealEstateInvestments	1297314000	usd
CY2024Q3	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	1048126000	usd
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CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1425000	usd
CY2024Q3	us-gaap	Investments Investments	27827496000	usd
CY2024Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1573238000	usd
CY2024Q3	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	38071000	usd
CY2024Q3	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	830797000	usd
CY2024Q3	us-gaap	Receivables From Brokers Dealers And Clearing Organizations ReceivablesFromBrokersDealersAndClearingOrganizations	410756000	usd
CY2024Q3	us-gaap	Premiums Written Net PremiumsWrittenNet	3057276000	usd
CY2024Q3	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	-130453000	usd
CY2024Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	2926823000	usd
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CY2024Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1825960000	usd
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CY2024Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-320000	usd
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	us-gaap	Profit Loss ProfitLoss	1179234000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	49503000	usd
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	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	25160000	usd
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	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	322693000	usd
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	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1501927000	usd
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	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-779000	usd
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.81
	us-gaap	Net Income Loss NetIncomeLoss	1180014000	usd
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-40818000	usd
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-780000	usd
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	868000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	40319000	usd
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	-36714000	usd
	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	-85226000	usd
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	94393000	usd
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-16825000	usd
	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	1402623000	usd
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	569416000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	61241000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2868335000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1688623000	usd
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	wrb	Payments To Acquire Equity Securities Available For Sale PaymentsToAcquireEquitySecuritiesAvailableForSale	186382000	usd
	wrb	Increase Decrease In Broker Dealer Related Receivables Payables Net Investing Activities IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNetInvestingActivities	-122519000	usd
	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	usd
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-320000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1396536000	usd
	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	1954000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	186921000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	430536000	usd
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-20545000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-638856000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	959000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	196728000	usd
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	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	400302000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	407484000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	404053000	shares
CY2024Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	34000	usd
CY2023Q2	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	53000	usd
CY2023Q3	us-gaap	Debt Securities Held To Maturity Credit Loss Expense Reversal DebtSecuritiesHeldToMaturityCreditLossExpenseReversal	-5000	usd
CY2023Q3	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	48000	usd
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity Registrant Name EntityRegistrantName	W. R. BERKLEY CORP
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	22-1867895
	dei	Local Phone Number LocalPhoneNumber	629-3000
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CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	3004000	usd
CY2024Q3	us-gaap	Other Liabilities OtherLiabilities	1674405000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	1503053000	usd
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CY2024Q3	us-gaap	Junior Subordinated Notes JuniorSubordinatedNotes	1009629000	usd
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CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	109135000	usd
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	us-gaap	Net Income Loss NetIncomeLoss	1180014000	usd
	us-gaap	Net Income Loss NetIncomeLoss	984020000	usd
CY2024Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.92
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.83
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.95
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.41
CY2024Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.91
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	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.92
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.39
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-7387000	usd
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-50850000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-58237000	usd
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	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	862000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	796130000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	192440000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1502706000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	925784000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.33
CY2023Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.41
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.88
CY2024Q3	us-gaap	Stockholders Equity Other StockholdersEquityOther	-321000	usd
CY2023Q3	us-gaap	Stockholders Equity Other StockholdersEquityOther	-326000	usd
	us-gaap	Stockholders Equity Other StockholdersEquityOther	1849000	usd
	us-gaap	Stockholders Equity Other StockholdersEquityOther	3899000	usd
	us-gaap	Net Income Loss NetIncomeLoss	984020000	usd
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	39239000	usd
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	863000	usd
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	5444000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	37796000	usd
	us-gaap	Increase Decrease In Trading Securities IncreaseDecreaseInTradingSecurities	41399000	usd
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	311827000	usd
	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	340056000	usd
	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	194610000	usd
	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	93270000	usd
	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-49722000	usd
	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	1288975000	usd
	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	608300000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2231162000	usd
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	877019000	usd
	wrb	Proceeds From Sale Of Equity Securities Available For Sale ProceedsFromSaleOfEquitySecuritiesAvailableForSale	161470000	usd
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	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	3483326000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	2654140000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	7177379000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	5091866000	usd
	wrb	Payments To Acquire Equity Securities Available For Sale PaymentsToAcquireEquitySecuritiesAvailableForSale	63815000	usd
	wrb	Payments For Proceeds From Real Estate PaymentsForProceedsFromRealEstate	15158000	usd
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	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	94076000	usd
CY2022Q4	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	37352000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	2048000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	940000	usd
CY2023Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	188141000	usd
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2024
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
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	dei	Entity Address Address Line1 EntityAddressAddressLine1	475 Steamboat Road
	dei	Entity Address City Or Town EntityAddressCityOrTown	Greenwich
	dei	Entity Address State Or Province EntityAddressStateOrProvince	CT
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	06830
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	dei	Trading Symbol TradingSymbol	WRB
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	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
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CY2024Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	381069120	shares
CY2024Q3	wrb	Debt Securities Availableforsaleand Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityAmortizedCost	23003148000	usd
CY2023Q4	wrb	Debt Securities Availableforsaleand Heldtomaturity Amortized Cost DebtSecuritiesAvailableforsaleandHeldtomaturityAmortizedCost	20915245000	usd
CY2024Q3	wrb	Debt Securities Allowancefor Credit Loss DebtSecuritiesAllowanceforCreditLoss	6983000	usd
CY2023Q4	wrb	Debt Securities Allowancefor Credit Loss DebtSecuritiesAllowanceforCreditLoss	36751000	usd
CY2023Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity DebtSecuritiesAvailableForSaleAndHeldToMaturity	20178308000	usd
CY2023Q4	us-gaap	Real Estate Investments RealEstateInvestments	1249874000	usd
CY2024Q3	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	389869000	usd
CY2023Q4	us-gaap	Mortgage Loans On Real Estate Commercial And Consumer Net MortgageLoansOnRealEstateCommercialAndConsumerNet	201271000	usd
CY2023Q4	us-gaap	Investments Investments	25279504000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1363195000	usd
CY2023Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	35110000	usd
CY2024Q3	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	3414385000	usd
CY2023Q4	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	3109334000	usd
CY2024Q3	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	8332000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	8404000	usd
CY2024Q3	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	3478354000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables On Paid And Unpaid Losses ReinsuranceRecoverablesOnPaidAndUnpaidLosses	3534527000	usd
CY2024Q3	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	957997000	usd
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CY2023Q4	us-gaap	Prepaid Reinsurance Premiums PrepaidReinsurancePremiums	758927000	usd
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CY2024Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	478361000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	426803000	usd
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CY2024Q3	wrb	Income Taxes Net Current And Deferred IncomeTaxesNetCurrentAndDeferred	131209000	usd
CY2023Q4	wrb	Income Taxes Net Current And Deferred IncomeTaxesNetCurrentAndDeferred	220756000	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	838532000	usd
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CY2024Q3	us-gaap	Assets Assets	40359298000	usd
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CY2024Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	20155310000	usd
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CY2024Q3	us-gaap	Unearned Premiums UnearnedPremiums	6489597000	usd
CY2024Q3	us-gaap	Reinsurance Payable ReinsurancePayable	727074000	usd
CY2023Q4	us-gaap	Reinsurance Payable ReinsurancePayable	631164000	usd
CY2024Q3	us-gaap	Trading Liabilities TradingLiabilities	36093000	usd
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CY2024Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.20
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CY2023Q4	us-gaap	Common Stock Value CommonStockValue	158705000	usd
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CY2024Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	381189906	shares
CY2024Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	381189906	shares
CY2024Q3	us-gaap	Common Stock Value CommonStockValue	158705000	usd
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CY2023Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	1636193000	usd
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CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	398338000	shares
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	403787000	shares
CY2024Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	401817000	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	407158000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	411219000	shares
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CY2023Q4	us-gaap	Debt Securities Available For Sale And Held To Maturity Fair Value DebtSecuritiesAvailableForSaleAndHeldToMaturityFairValue	20181547000	usd
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CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	384817136	shares
CY2023Q3	us-gaap	Profit Loss ProfitLoss	333430000	usd
	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-27790000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-173236000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	4973000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-30863000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	4046000	usd
	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	7000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	6953000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	46364000	usd
CY2023Q2	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	44248000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	47000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not Previously Recorded DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotPreviouslyRecorded	2482000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-14552000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal	-366000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	379000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss Securities Sold DebtSecuritiesAvailableForSaleAllowanceForCreditLossSecuritiesSold	0	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	6953000	usd
CY2023Q3	us-gaap	Debt Securities Available For Sale Allowance For Credit Loss DebtSecuritiesAvailableForSaleAllowanceForCreditLoss	46364000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities Within One Year Amortized Cost MarketableSecuritiesFixedMaturitiesWithinOneYearAmortizedCost	1910941000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities Within One Year Fair Value MarketableSecuritiesFixedMaturitiesWithinOneYearFairValue	1886626000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After One Through Five Years Amortized Cost MarketableSecuritiesFixedMaturitiesAfterOneThroughFiveYearsAmortizedCost	9907127000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After One Through Five Years Fair Value MarketableSecuritiesFixedMaturitiesAfterOneThroughFiveYearsFairValue	9724883000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After Five Through Ten Years Amortized Cost MarketableSecuritiesFixedMaturitiesAfterFiveThroughTenYearsAmortizedCost	4282838000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After Five Through Ten Years Fair Value MarketableSecuritiesFixedMaturitiesAfterFiveThroughTenYearsFairValue	4283690000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After Ten Years Amortized Cost MarketableSecuritiesFixedMaturitiesAfterTenYearsAmortizedCost	3562724000	usd
CY2024Q3	wrb	Marketable Securities Fixed Maturities After Ten Years Fair Value MarketableSecuritiesFixedMaturitiesAfterTenYearsFairValue	3530253000	usd
CY2024Q3	wrb	Marketable Securities Debt Maturities Without Single Maturity Date Amortized Cost MarketableSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost	3339488000	usd
CY2024Q3	wrb	Marketable Securities Debt Maturities Without Single Maturity Date Fair Value MarketableSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue	3240479000	usd
CY2024Q3	wrb	Debt Securities Availableforsaleand Heldtomaturity Amortized Cost Net DebtSecuritiesAvailableforsaleandHeldtomaturityAmortizedCostNet	23003118000	usd
CY2024Q3	us-gaap	Debt Securities Available For Sale And Held To Maturity Fair Value DebtSecuritiesAvailableForSaleAndHeldToMaturityFairValue	22665931000	usd
CY2024Q3	us-gaap	Debt Securities Held To Maturity Allowance For Credit Loss DebtSecuritiesHeldToMaturityAllowanceForCreditLoss	30000	usd
CY2024Q3	us-gaap	Trading Securities TradingSecurities	821000000	usd
CY2023Q4	us-gaap	Trading Securities TradingSecurities	938000000	usd
CY2024Q3	wrb	Investment Income Loss Interest And Dividend InvestmentIncomeLossInterestAndDividend	326374000	usd
CY2023Q3	wrb	Investment Income Loss Interest And Dividend InvestmentIncomeLossInterestAndDividend	272781000	usd
	wrb	Investment Income Loss Interest And Dividend InvestmentIncomeLossInterestAndDividend	1023430000	usd
	wrb	Investment Income Loss Interest And Dividend InvestmentIncomeLossInterestAndDividend	745705000	usd
CY2024Q3	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	2618000	usd
CY2023Q3	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	1837000	usd
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	7707000	usd
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6211000	usd
CY2024Q3	us-gaap	Net Investment Income NetInvestmentIncome	323756000	usd
CY2023Q3	us-gaap	Net Investment Income NetInvestmentIncome	270944000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	1015723000	usd
	us-gaap	Net Investment Income NetInvestmentIncome	739494000	usd
CY2024Q3	wrb	Nonconsolidated Legal Entity Unfunded Commitments NonconsolidatedLegalEntityUnfundedCommitments	248000000	usd
CY2024Q3	us-gaap	Equity Method Investments EquityMethodInvestments	1607381000	usd
CY2023Q4	us-gaap	Equity Method Investments EquityMethodInvestments	1621655000	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	868000	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	5444000	usd
CY2024Q3	wrb	Buildingand Lease Obligations BuildingandLeaseObligations	1069589000	usd
CY2023Q4	wrb	Buildingand Lease Obligations BuildingandLeaseObligations	1022654000	usd
CY2024Q3	us-gaap	Development In Process DevelopmentInProcess	227725000	usd
CY2023Q4	us-gaap	Development In Process DevelopmentInProcess	227220000	usd
CY2024Q3	us-gaap	Real Estate Investment Property Net RealEstateInvestmentPropertyNet	1297314000	usd
CY2023Q4	us-gaap	Real Estate Investment Property Net RealEstateInvestmentPropertyNet	1249874000	usd
CY2024Q3	us-gaap	Real Estate Investment Property Accumulated Depreciation RealEstateInvestmentPropertyAccumulatedDepreciation	36999000	usd
CY2023Q4	us-gaap	Real Estate Investment Property Accumulated Depreciation RealEstateInvestmentPropertyAccumulatedDepreciation	32745000	usd
	wrb	Operating Lease Right Of Use Asset Accumulated Depreciation OperatingLeaseRightOfUseAssetAccumulatedDepreciation	6401000	usd
	wrb	Operating Lease Right Of Use Asset Accumulated Depreciation OperatingLeaseRightOfUseAssetAccumulatedDepreciation	6667000	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Remainder Of Fiscal Year LessorOperatingLeasePaymentsToBeReceivedRemainderOfFiscalYear	8884653	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	34771667	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	33308460	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	32567952	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	33133057	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	28606364	usd
CY2024Q3	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	415176586	usd
CY2024Q3	us-gaap	Notes Receivable Net NotesReceivableNet	389869000	usd
CY2023Q4	us-gaap	Notes Receivable Net NotesReceivableNet	201271000	usd
CY2024Q3	us-gaap	Notes Receivable Fair Value Disclosure NotesReceivableFairValueDisclosure	389861000	usd
CY2023Q4	us-gaap	Notes Receivable Fair Value Disclosure NotesReceivableFairValueDisclosure	198244000	usd
CY2023Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	3004000	usd
CY2022Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1791000	usd
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-1579000	usd
	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	2218000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1425000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	4009000	usd
CY2024Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1813000	usd
CY2023Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	4550000	usd
CY2024Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-388000	usd
CY2023Q3	us-gaap	Provision For Loan Losses Expensed ProvisionForLoanLossesExpensed	-541000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	1425000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	4009000	usd
CY2024Q3	wrb	Availablefor Saleand Heldto Maturity Realized Gains Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedGainsDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	4799000	usd
CY2023Q3	wrb	Availablefor Saleand Heldto Maturity Realized Gains Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedGainsDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	299000	usd
	wrb	Availablefor Saleand Heldto Maturity Realized Gains Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedGainsDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	11448000	usd
	wrb	Availablefor Saleand Heldto Maturity Realized Gains Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedGainsDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	1357000	usd
CY2024Q3	wrb	Availablefor Saleand Heldto Maturity Realized Losses Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedLossesDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	3884000	usd
CY2023Q3	wrb	Availablefor Saleand Heldto Maturity Realized Losses Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedLossesDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	2700000	usd
	wrb	Availablefor Saleand Heldto Maturity Realized Losses Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedLossesDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	11569000	usd
	wrb	Availablefor Saleand Heldto Maturity Realized Losses Debt Securities Excluding Otherthan Temporary Impairmentsand Allowances AvailableforSaleandHeldtoMaturityRealizedLossesDebtSecuritiesExcludingOtherthanTemporaryImpairmentsandAllowances	24470000	usd
CY2024Q3	wrb	Availableforsale Securities Gross Realized Gain Loss Equity Securities Excluding Otherthan Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossEquitySecuritiesExcludingOtherthanTemporaryImpairments	407000	usd
CY2023Q3	wrb	Availableforsale Securities Gross Realized Gain Loss Equity Securities Excluding Otherthan Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossEquitySecuritiesExcludingOtherthanTemporaryImpairments	23631000	usd
	wrb	Availableforsale Securities Gross Realized Gain Loss Equity Securities Excluding Otherthan Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossEquitySecuritiesExcludingOtherthanTemporaryImpairments	102205000	usd
	wrb	Availableforsale Securities Gross Realized Gain Loss Equity Securities Excluding Otherthan Temporary Impairments AvailableforsaleSecuritiesGrossRealizedGainLossEquitySecuritiesExcludingOtherthanTemporaryImpairments	135763000	usd
CY2024Q3	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-1537000	usd
CY2023Q3	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-19059000	usd
	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-42442000	usd
	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	45605000	usd
CY2024Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	-101000	usd
CY2023Q3	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	-3329000	usd
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	1109000	usd
	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	-3417000	usd
CY2024Q3	wrb	Real Estate Realized Gain Loss On Disposal RealEstateRealizedGainLossOnDisposal	1470000	usd
CY2023Q3	wrb	Real Estate Realized Gain Loss On Disposal RealEstateRealizedGainLossOnDisposal	-24234000	usd
	wrb	Real Estate Realized Gain Loss On Disposal RealEstateRealizedGainLossOnDisposal	-2704000	usd
	wrb	Real Estate Realized Gain Loss On Disposal RealEstateRealizedGainLossOnDisposal	-68944000	usd
CY2024Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	0	usd
CY2023Q3	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	-1428000	usd
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	0	usd
	us-gaap	Gain Loss On Sales Of Loans Net GainLossOnSalesOfLoansNet	-1428000	usd
CY2024Q3	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-24516000	usd
CY2023Q3	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-14035000	usd
	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-130212000	usd
	us-gaap	Gain Loss On Sale Of Other Investments GainLossOnSaleOfOtherInvestments	-34063000	usd
CY2024Q3	wrb	Realized Gain Losson Investments Including Equity Method Investments Excluding Otherthan Temporary Impairmentsand Allowances RealizedGainLossonInvestmentsIncludingEquityMethodInvestmentsExcludingOtherthanTemporaryImpairmentsandAllowances	-23362000	usd
CY2023Q3	wrb	Realized Gain Losson Investments Including Equity Method Investments Excluding Otherthan Temporary Impairmentsand Allowances RealizedGainLossonInvestmentsIncludingEquityMethodInvestmentsExcludingOtherthanTemporaryImpairmentsandAllowances	-40855000	usd
	wrb	Realized Gain Losson Investments Including Equity Method Investments Excluding Otherthan Temporary Impairmentsand Allowances RealizedGainLossonInvestmentsIncludingEquityMethodInvestmentsExcludingOtherthanTemporaryImpairmentsandAllowances	-72165000	usd
	wrb	Realized Gain Losson Investments Including Equity Method Investments Excluding Otherthan Temporary Impairmentsand Allowances RealizedGainLossonInvestmentsIncludingEquityMethodInvestmentsExcludingOtherthanTemporaryImpairmentsandAllowances	50403000	usd
CY2024Q3	wrb	Debt Securities Allowancefor Credit Loss Period Increase Decrease DebtSecuritiesAllowanceforCreditLossPeriodIncreaseDecrease	14888000	usd
CY2023Q3	wrb	Debt Securities Allowancefor Credit Loss Period Increase Decrease DebtSecuritiesAllowanceforCreditLossPeriodIncreaseDecrease	-2112000	usd
	wrb	Debt Securities Allowancefor Credit Loss Period Increase Decrease DebtSecuritiesAllowanceforCreditLossPeriodIncreaseDecrease	29768000	usd
	wrb	Debt Securities Allowancefor Credit Loss Period Increase Decrease DebtSecuritiesAllowanceforCreditLossPeriodIncreaseDecrease	-8946000	usd
CY2024Q3	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	388000	usd
CY2023Q3	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	541000	usd
	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	1579000	usd
	us-gaap	Financing Receivable Allowance For Credit Losses Period Increase Decrease FinancingReceivableAllowanceForCreditLossesPeriodIncreaseDecrease	-2218000	usd
CY2024Q3	wrb	Investments Allowancefor Credit Loss Period Increase Decrease InvestmentsAllowanceforCreditLossPeriodIncreaseDecrease	15276000	usd
CY2023Q3	wrb	Investments Allowancefor Credit Loss Period Increase Decrease InvestmentsAllowanceforCreditLossPeriodIncreaseDecrease	-1571000	usd
	wrb	Investments Allowancefor Credit Loss Period Increase Decrease InvestmentsAllowanceforCreditLossPeriodIncreaseDecrease	31347000	usd
	wrb	Investments Allowancefor Credit Loss Period Increase Decrease InvestmentsAllowanceforCreditLossPeriodIncreaseDecrease	-11164000	usd
CY2024Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-8086000	usd
CY2023Q3	us-gaap	Gain Loss On Investments GainLossOnInvestments	-42426000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	-40818000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	39239000	usd
CY2024Q3	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsTax	-43000	usd
CY2023Q3	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsTax	-9405000	usd
	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsTax	-5810000	usd
	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsTax	8033000	usd
CY2024Q3	wrb	Marketable Securities Realized Gain Loss Excluding Otherthan Temporary Impairments Netof Tax MarketableSecuritiesRealizedGainLossExcludingOtherthanTemporaryImpairmentsNetofTax	-8043000	usd
CY2023Q3	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Netof Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsNetofTax	-33021000	usd
	wrb	Marketable Securities Realized Gain Loss Excluding Otherthan Temporary Impairments Netof Tax MarketableSecuritiesRealizedGainLossExcludingOtherthanTemporaryImpairmentsNetofTax	-35008000	usd
	wrb	Realized Gain Losson Marketable Securities Equity Method Investmentsand Other Investments Netof Tax RealizedGainLossonMarketableSecuritiesEquityMethodInvestmentsandOtherInvestmentsNetofTax	31206000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	480768000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-150455000	usd
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	370831000	usd
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Before Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentBeforeTax	-62476000	usd
CY2024Q3	wrb	Changein Unrealized Gainlosson Investmentstax ChangeinUnrealizedGainlossonInvestmentstax	99775000	usd
CY2023Q3	wrb	Changein Unrealized Gainlosson Investmentstax ChangeinUnrealizedGainlossonInvestmentstax	-32090000	usd
	wrb	Changein Unrealized Gainlosson Investmentstax ChangeinUnrealizedGainlossonInvestmentstax	73298000	usd
	wrb	Changein Unrealized Gainlosson Investmentstax ChangeinUnrealizedGainlossonInvestmentstax	-11626000	usd
CY2024Q3	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterest	0	usd
CY2023Q3	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterest	0	usd
	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterest	-1000	usd
	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterest	1000	usd
CY2024Q3	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest Netof Tax ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterestNetofTax	380993000	usd
CY2023Q3	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest Netof Tax ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterestNetofTax	-118365000	usd
	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest Netof Tax ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterestNetofTax	297534000	usd
	wrb	Changein Unrealized Gainlosson Investments Including Portion Attributableto Noncontrolling Interest Netof Tax ChangeinUnrealizedGainlossonInvestmentsIncludingPortionAttributabletoNoncontrollingInterestNetofTax	-50851000	usd
CY2023Q2	us-gaap	Gain On Sale Of Investments GainOnSaleOfInvestments	88000000	usd
CY2023Q3	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	21000000	usd
	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	72000000	usd
CY2023Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	9025000	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	718000	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	usd
	wrb	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Asset Impairment FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisAssetImpairment	0	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	223000	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	usd
	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	37000	usd
CY2024Q3	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	9557000	usd
CY2022Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	17488000	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Earnings1 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1	-927000	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Gain Loss Included In Other Comprehensive Income Loss FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss	0	usd
CY2023	wrb	Fair Value Measurementwith Unobservable Inputs Reconciliation Recurring Basis Asset Impairment FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisAssetImpairment	7601000	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases	0	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales	0	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements	0	usd
CY2023	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3 FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3	65000	usd
CY2023Q4	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue	9025000	usd
	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	The table below provides a reconciliation of the beginning and ending reserve balances:<div style="margin-top:5pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.707%"><tr><td style="width:1.0%"></td><td style="width:76.759%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.603%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.533%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:9.605%"></td><td style="width:0.1%"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="padding:0 1pt"></td><td colspan="9" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">September 30,</span></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%;text-decoration:underline">(In thousands)</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">2024</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></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:9pt;font-weight:400;line-height:100%">Net reserves at beginning of period</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:9pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">15,661,820 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</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:9pt;font-weight:400;line-height:100%">14,248,879 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Net provision for losses and loss expenses:</span></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></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:9pt;font-weight:400;line-height:100%">Claims occurring during the current year (1)</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:9pt;font-weight:400;line-height:100%">5,229,468 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></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:9pt;font-weight:400;line-height:100%">4,694,554 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="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:9pt;font-weight:400;line-height:100%">Increase in estimates for claims occurring in prior years (2) (3)</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">15,279 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">27,186 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></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:9pt;font-weight:400;line-height:100%">Loss reserve discount accretion </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:9pt;font-weight:400;line-height:100%">25,587 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></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:9pt;font-weight:400;line-height:100%">22,862 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="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:9pt;font-weight:400;line-height:100%">Total</span></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">5,270,334 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">4,744,602 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></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:9pt;font-weight:400;line-height:100%">Net payments for claims:</span></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="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:9pt;font-weight:400;line-height:100%">Current year</span></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">795,792 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="2" style="padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">743,416 </span></td><td style="padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></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:9pt;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:9pt;font-weight:400;line-height:100%">3,164,720 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></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:9pt;font-weight:400;line-height:100%">2,915,979 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="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:9pt;font-weight:400;line-height:100%">Total</span></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">3,960,512 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">3,659,395 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></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:9pt;font-weight:400;line-height:100%">Foreign currency translation</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:9pt;font-weight:400;line-height:100%">19,659 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></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:9pt;font-weight:400;line-height:100%">(48,162)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Net reserves at end of period</span></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">16,991,301 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td colspan="2" style="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:9pt;font-weight:400;line-height:100%">15,285,924 </span></td><td style="border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></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:9pt;font-weight:400;line-height:100%">Ceded reserves at end of period</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:9pt;font-weight:400;line-height:100%">3,164,009 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></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:9pt;font-weight:400;line-height:100%">2,987,386 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Gross reserves at end of period</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">20,155,310 </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="padding:0 1pt"></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">$</span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">18,273,310 </span></td><td style="border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="display:none"></td><td colspan="3" style="display:none"></td></tr></table></div><div style="margin-top:1pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">_______________________________________</span></div><div style="margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(1) Claims occurring during the current year are net of loss reserve discounts of $37 million and $35 million for the nine months ended September 30, 2024 and 2023, respectively.</span></div><div style="margin-bottom:3pt;margin-top:6pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(2) The change in estimates for claims occurring in prior years is net of loss reserve discount. On an undiscounted basis, the estimates for claims occurring in prior years increased by $12 million and decreased by $12 million for the nine months ended September 30, 2024 and 2023, respectively. </span></div><div style="margin-bottom:6pt;margin-top:6pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">(3) For certain retrospectively rated insurance policies and reinsurance agreements, reserve development is offset by additional or return premiums. Favorable development, net of additional and return premiums, was $3 million and adverse development was $20 million for the nine months ended September 30, 2024 and 2023, respectively.</span></div>
CY2023Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	15661820000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	14248879000	usd
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	5229468000	usd
	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	4694554000	usd
	wrb	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Incurred Claims Adjustment LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseIncurredClaimsAdjustment	-15279000	usd
	wrb	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Incurred Claims Adjustment LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseIncurredClaimsAdjustment	-27186000	usd
	wrb	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Loss Reserve Discount Accretion LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredLossReserveDiscountAccretion	-25587000	usd
	wrb	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Loss Reserve Discount Accretion LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredLossReserveDiscountAccretion	-22862000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	5270334000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	4744602000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	795792000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	743416000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	3164720000	usd
	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	2915979000	usd
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	3960512000	usd
	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	3659395000	usd
	wrb	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Foreign Exchange Translation LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseForeignExchangeTranslation	19659000	usd
	wrb	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Foreign Exchange Translation LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseForeignExchangeTranslation	-48162000	usd
CY2024Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	16991301000	usd
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2024 Q4 Form 10-Q Financial Statement

#000001154424000028 Filed on November 04, 2024

Income Statement

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$WRB BERKLEY W R CORP Stock $wrb

2024 Q4 Form 10-Q Financial Statement

#000001154424000028 Filed on November 04, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WRB
BERKLEY W R CORP Stock $wrb