$MCY
MERCURY GENERAL CORP Stock $mcy

$mcy Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000006499624000002 Filed on February 13, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$1.274B	$1.375B	$4.630B
YoY Change	15.14%	19.36%	27.08%
Cost Of Revenue	$3.200M		$11.40M
YoY Change	10.34%		3.64%
Gross Profit	$1.271B		$4.618B
YoY Change	15.15%		27.15%
Gross Profit Margin	99.75%		99.75%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$196.0M	$20.77M	$33.80M
YoY Change	19.15%	-32.98%	-1.46%
% of Gross Profit	15.42%		0.73%
Operating Expenses	$1.177B	$1.129B	$4.506B
YoY Change	1.15%	-3.07%	4.88%
Operating Profit	$93.79M		$112.2M
YoY Change	-256.2%		-116.88%
Interest Expense	$7.800M	-$7.771M	$24.20M
YoY Change	59.18%	76.21%	40.7%
% of Operating Profit	8.32%		21.57%
Other Income/Expense, Net
YoY Change
Pretax Income	$89.20M	$237.9M	$99.40M
YoY Change	-243.64%	-1472.07%	-114.82%
Income Tax	$15.76M	$46.55M	$3.092M
% Of Pretax Income	17.67%	19.56%	3.11%
Net Earnings	$73.50M	$191.4M	$96.30M
YoY Change	-262.25%	-2927.09%	-118.78%
Net Earnings / Revenue	5.77%	13.92%	2.08%
Basic Earnings Per Share	$1.33		$1.74
Diluted Earnings Per Share	$1.33	$3.46	$1.74
COMMON SHARES
Basic Shares Outstanding	55.37M shares	55.37M shares	55.37M shares
Diluted Shares Outstanding	55.37M shares		55.37M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$530.1M	$550.9M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$30.04M	$25.60M	$25.60M
YoY Change	39.72%	125.42%	125.42%
LONG-TERM ASSETS
Property, Plant & Equipment	$152.5M	$151.2M	$168.6M
YoY Change	-3.84%	-11.82%	-13.92%
Goodwill	$42.80M	$42.80M
YoY Change	0.0%	0.0%
Intangibles	$8.353M	$8.333M
YoY Change	-7.11%	-9.54%
Long-Term Investments	$5.453B	$5.229B	$5.229B
YoY Change	9.61%	6.47%	6.47%
Other Assets	$31.37M	$33.01M	$33.01M
YoY Change	-14.95%	-23.05%	-23.05%
Total Long-Term Assets	$7.366B	$7.078B	$7.078B
YoY Change	12.15%	8.84%	8.84%
TOTAL ASSETS
Total Short-Term Assets	$30.04M	$25.60M	$25.60M
Total Long-Term Assets	$7.366B	$7.078B	$7.078B
Total Assets	$7.396B	$7.103B	$7.103B
YoY Change	12.24%	9.05%	9.05%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$178.1M	$175.2M	$175.2M
YoY Change	17.62%	15.51%	15.51%
Accrued Expenses	$14.43M	$14.23M	$14.23M
YoY Change	-25.58%	-35.09%	-35.09%
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	$199.1M	$189.5M	$189.5M
YoY Change	16.59%	9.12%	9.12%
LONG-TERM LIABILITIES
Long-Term Debt	$573.8M	$573.7M	$576.6M
YoY Change	27.96%	44.03%	43.46%
Other Long-Term Liabilities	$305.6M	$270.7M	$267.9M
YoY Change	8.37%	-6.51%	-6.34%
Total Long-Term Liabilities	$879.4M	$844.4M	$844.4M
YoY Change	20.4%	22.76%	22.76%
TOTAL LIABILITIES
Total Short-Term Liabilities	$199.1M	$189.5M	$189.5M
Total Long-Term Liabilities	$879.4M	$844.4M	$844.4M
Total Liabilities	$5.792B	$5.555B	$5.555B
YoY Change	12.9%	11.28%	11.28%
SHAREHOLDERS EQUITY
Retained Earnings	$1.505B	$1.449B
YoY Change	10.64%	1.83%
Common Stock	$98.95M	$98.95M
YoY Change	0.0%	0.0%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.604B	$1.548B	$1.548B
YoY Change
Total Liabilities & Shareholders Equity	$7.396B	$7.103B	$7.103B
YoY Change	12.24%	9.05%	9.05%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$73.50M	$191.4M	$96.30M
YoY Change	-262.25%	-2927.09%	-118.78%
Depreciation, Depletion And Amortization	$196.0M	$20.77M	$33.80M
YoY Change	19.15%	-32.98%	-1.46%
Cash From Operating Activities	$192.6M	$225.3M	$453.0M
YoY Change	959.96%	232.69%	28.47%
INVESTING ACTIVITIES
Capital Expenditures	$10.27M	$9.810M	$36.81M
YoY Change	18.26%	-1.1%	3.67%
Acquisitions
YoY Change
Other Investing Activities	-$4.044M	-$100.7M	-$10.38M
YoY Change	145.69%	-9.23%	80.41%
Cash From Investing Activities	-$194.9M	-$110.5M	-$295.4M
YoY Change	180.4%	-8.56%	-6.62%
FINANCING ACTIVITIES
Cash Dividend Paid			$70.32M
YoY Change			-33.33%
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$18.57M	-17.82M	$103.6M
YoY Change	-158.14%	-352.36%	-226.33%
NET CHANGE
Cash From Operating Activities	$192.6M	225.3M	$453.0M
Cash From Investing Activities	-$194.9M	-110.5M	-$295.4M
Cash From Financing Activities	-$18.57M	-17.82M	$103.6M
Net Change In Cash	-$20.82M	96.93M	$261.1M
YoY Change	7.33%	-310.21%	-670.38%
FREE CASH FLOW
Cash From Operating Activities	$192.6M	$225.3M	$453.0M
Capital Expenditures	$10.27M	$9.810M	$36.81M
Free Cash Flow	$182.4M	$215.5M	$416.2M
YoY Change	1821.95%	272.81%	31.25%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2023	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	279656000	usd
CY2022	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	279718000	usd
CY2023	us-gaap	Interest Expense InterestExpense	24169000	usd
CY2022	us-gaap	Interest Expense InterestExpense	17232000	usd
CY2021	us-gaap	Interest Expense InterestExpense	17113000	usd
CY2023	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	4530203000	usd
CY2021	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	3694050000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-670715000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	299307000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51370000	usd
CY2021	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	518557000	usd
CY2022	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	1042913000	usd
CY2023	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	708525000	usd
CY2022	mcy	Increase Decrease In Securities Payable And Receivable IncreaseDecreaseInSecuritiesPayableAndReceivable	-22124000	usd
CY2021	mcy	Increase Decrease In Securities Payable And Receivable IncreaseDecreaseInSecuritiesPayableAndReceivable	-8327000	usd
CY2023	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	48446000	usd
CY2022	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-38141000	usd
CY2023	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	36810000	usd
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0000064996
CY2022Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssets
CY2023Q4	us-gaap	Finance Lease Liability Statement Of Financial Position Extensible List FinanceLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2022Q4	us-gaap	Finance Lease Liability Statement Of Financial Position Extensible List FinanceLeaseLiabilityStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilities
CY2022	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#RealizedInvestmentGainsLosses
CY2023	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#RealizedInvestmentGainsLosses
CY2021	us-gaap	Derivative Gain Loss Statement Of Income Or Comprehensive Income Extensible Enumeration DerivativeGainLossStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration	http://fasb.org/us-gaap/2023#RealizedInvestmentGainsLosses
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	001-12257
CY2023	dei	Entity Registrant Name EntityRegistrantName	MERCURY GENERAL CORPORATION
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	CA
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	95-2211612
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	4484 Wilshire Boulevard
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	Los Angeles,
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	90010
CY2023	dei	City Area Code CityAreaCode	323
CY2023	dei	Local Phone Number LocalPhoneNumber	937-1060
CY2023	dei	Security12b Title Security12bTitle	Common Stock
CY2023	dei	Trading Symbol TradingSymbol	MCY
CY2023	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2023	dei	Entity Small Business EntitySmallBusiness	false
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023Q2	dei	Entity Public Float EntityPublicFloat	803841584	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	55371127	shares
CY2023	dei	Auditor Firm AuditorFirmId	185
CY2023	dei	Auditor Name AuditorName	KPMG LLP
CY2023	dei	Auditor Location AuditorLocation	Los Angeles, California
CY2023Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	4394983000	usd
CY2022Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	4226790000	usd
CY2023Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	4319336000	usd
CY2022Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	4088311000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	654939000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	668843000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	730693000	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni EquitySecuritiesFvNi	699552000	usd
CY2023Q4	mcy	Other Short Term Investments Cost OtherShortTermInvestmentsCost	179375000	usd
CY2022Q4	mcy	Other Short Term Investments Cost OtherShortTermInvestmentsCost	123928000	usd
CY2023Q4	us-gaap	Other Short Term Investments OtherShortTermInvestments	178491000	usd
CY2022Q4	us-gaap	Other Short Term Investments OtherShortTermInvestments	122937000	usd
CY2023Q4	us-gaap	Investments Investments	5228520000	usd
CY2022Q4	us-gaap	Investments Investments	4910800000	usd
CY2023Q4	us-gaap	Cash Cash	550903000	usd
CY2022Q4	us-gaap	Cash Cash	289776000	usd
CY2023Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	607025000	usd
CY2022Q4	us-gaap	Premiums Receivable Gross PremiumsReceivableGross	571910000	usd
CY2023Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5300000	usd
CY2022Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5800000	usd
CY2023Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	601725000	usd
CY2022Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	566110000	usd
CY2023Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	59128000	usd
CY2022Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	52474000	usd
CY2023Q4	us-gaap	Other Receivables OtherReceivables	25603000	usd
CY2022Q4	us-gaap	Other Receivables OtherReceivables	11358000	usd
CY2023Q4	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	686456000	usd
CY2022Q4	us-gaap	Premiums And Other Receivables Net PremiumsAndOtherReceivablesNet	629942000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	12000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	usd
CY2023Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	31947000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables ReinsuranceRecoverables	25895000	usd
CY2023Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	293844000	usd
CY2022Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	266475000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	151183000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	171442000	usd
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	14406000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	20183000	usd
CY2023Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	4081000	usd
CY2022Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	55136000	usd
CY2023Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	33013000	usd
CY2022Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	42903000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	42796000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	42796000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	8333000	usd
CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	9212000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	57915000	usd
CY2022Q4	us-gaap	Other Assets OtherAssets	49628000	usd
CY2023Q4	us-gaap	Assets Assets	7103397000	usd
CY2022Q4	us-gaap	Assets Assets	6514188000	usd
CY2023Q4	us-gaap	Liability For Claims And Claims Adjustment Expense Property Casualty Liability LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability	2785702000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense Property Casualty Liability LiabilityForClaimsAndClaimsAdjustmentExpensePropertyCasualtyLiability	2584910000	usd
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CY2022Q4	us-gaap	Notes Payable NotesPayable	398330000	usd
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CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	14231000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	21924000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	270711000	usd
CY2022Q4	us-gaap	Other Liabilities OtherLiabilities	289568000	usd
CY2023Q4	us-gaap	Liabilities Liabilities	5555252000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	4992057000	usd
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2022Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	70000000	shares
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CY2023Q4	us-gaap	Common Stock Value CommonStockValue	98947000	usd
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	98947000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1449198000	usd
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CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1548145000	usd
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CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7103397000	usd
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CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.74
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-9.26
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.48
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CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-9.26
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.48
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1548145000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1522131000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2140281000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	96336000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	-512672000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	247937000	usd
CY2023	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	72240000	usd
CY2022	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	82390000	usd
CY2021	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	79056000	usd
CY2023	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	101014000	usd
CY2022	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-488080000	usd
CY2021	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	111658000	usd
CY2023	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	5879000	usd
CY2022	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-86000	usd
CY2021	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	17000	usd
CY2023	mcy	Gain Loss On Property Held For Sale GainLossOnPropertyHeldForSale	0	usd
CY2022	mcy	Gain Loss On Property Held For Sale GainLossOnPropertyHeldForSale	-841000	usd
CY2021	mcy	Gain Loss On Property Held For Sale GainLossOnPropertyHeldForSale	0	usd
CY2023	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	35615000	usd
CY2022	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	-49630000	usd
CY2021	us-gaap	Increase Decrease In Premiums Receivable IncreaseDecreaseInPremiumsReceivable	26670000	usd
CY2023	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	6052000	usd
CY2022	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	-19105000	usd
CY2021	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	-3488000	usd
CY2023	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-60945000	usd
CY2022	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	131500000	usd
CY2021	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	18097000	usd
CY2023	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	27369000	usd
CY2022	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	8216000	usd
CY2021	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	11265000	usd
CY2023	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	200792000	usd
CY2022	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	358480000	usd
CY2021	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	235126000	usd
CY2023	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	190021000	usd
CY2022	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	25840000	usd
CY2021	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	113926000	usd
CY2023	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	23162000	usd
CY2022	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-15844000	usd
CY2021	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	-26724000	usd
CY2023	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-14579000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-3631000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	16482000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	452988000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	352589000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	501584000	usd
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	784752000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1794817000	usd
CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	276805000	usd
CY2021	us-gaap	Payments To Acquire Equity Securities Fv Ni PaymentsToAcquireEquitySecuritiesFvNi	958008000	usd
CY2023	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	1356132000	usd
CY2022	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	1154523000	usd
CY2021	us-gaap	Proceeds From Sale Of Equity Securities Fv Ni ProceedsFromSaleOfEquitySecuritiesFvNi	943857000	usd
CY2021	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-270383000	usd
CY2022	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	35508000	usd
CY2021	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	41442000	usd
CY2023	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	29876000	usd
CY2022	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	3000	usd
CY2021	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	27000	usd
CY2023	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-10377000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5749000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-9069000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-295437000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-316384000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-373670000	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	70322000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	105482000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	140226000	usd
CY2023	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	215000	usd
CY2023	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1102000	usd
CY2022	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1504000	usd
CY2021	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	825000	usd
CY2023	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	175000000	usd
CY2022	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	25000000	usd
CY2021	us-gaap	Proceeds From Bank Debt ProceedsFromBankDebt	0	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	103576000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-81986000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-140836000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	261127000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-45781000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-12922000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	289776000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	335557000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	348479000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	550903000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	289776000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	335557000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	23000000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	16665000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	16616000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-57853000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-26542000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	69467000	usd
CY2023	mcy	Number Of Companies NumberOfCompanies	12	subsidiary
CY2023Q4	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	11	state
CY2023	mcy	Direct Premiums Written As Private Passenger Automobile Lines Of Insurance Percentage DirectPremiumsWrittenAsPrivatePassengerAutomobileLinesOfInsurancePercentage	0.62
CY2023	mcy	Private Passenger Automobile Premiums Written In California Percentage PrivatePassengerAutomobilePremiumsWrittenInCaliforniaPercentage	0.82
CY2022	mcy	Private Passenger Automobile Premiums Written In California Percentage PrivatePassengerAutomobilePremiumsWrittenInCaliforniaPercentage	0.82
CY2021	mcy	Private Passenger Automobile Premiums Written In California Percentage PrivatePassengerAutomobilePremiumsWrittenInCaliforniaPercentage	0.87
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	0	usd
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:6pt;text-align:justify;text-indent:27pt"><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, disclosures of contingent assets and liabilities at the date </span></div><div style="margin-top:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">of the financial statements, and the reported amounts of revenue and expenses during the reporting period. These estimates require the Company to apply complex assumptions and judgments, and often the Company must make estimates about effects of matters that are inherently uncertain and will likely change in subsequent periods. The most significant assumptions in the preparation of these consolidated financial statements relate to reserves for losses and loss adjustment expenses. Actual results could differ from those estimates.</span></div>
CY2023	mcy	Percentage Of Unadjusted Fair Value Obtained PercentageOfUnadjustedFairValueObtained	0.984
CY2023	mcy	Percentage By Which Dividend Income On Non Redeemable Preferred Stock Partnership Common Stock Is Partially Tax Sheltered PercentageByWhichDividendIncomeOnNonRedeemablePreferredStockPartnershipCommonStockIsPartiallyTaxSheltered	0.50
CY2023Q4	mcy	Security Deposits By Insurance Companies SecurityDepositsByInsuranceCompanies	15000000	usd
CY2022Q4	mcy	Security Deposits By Insurance Companies SecurityDepositsByInsuranceCompanies	14000000	usd
CY2023	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	708500000	usd
CY2022	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	654600000	usd
CY2021	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	633400000	usd
CY2023	us-gaap	Advertising Expense AdvertisingExpense	8900000	usd
CY2022	us-gaap	Advertising Expense AdvertisingExpense	11800000	usd
CY2021	us-gaap	Advertising Expense AdvertisingExpense	50100000	usd
CY2021	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	usd
CY2023	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	usd
CY2022	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	usd
CY2023	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2022	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023	us-gaap	Premiums Written Net PremiumsWrittenNet	4460000000	usd
CY2022	us-gaap	Premiums Written Net PremiumsWrittenNet	3980000000	usd
CY2021	us-gaap	Premiums Written Net PremiumsWrittenNet	3860000000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	30000000	usd
CY2023	us-gaap	Reinsurance Retention Policy Reinsured Risk Percentage ReinsuranceRetentionPolicyReinsuredRiskPercentage	0.735
CY2023	us-gaap	Ceded Premiums Earned CededPremiumsEarned	109000000	usd
CY2022	us-gaap	Ceded Premiums Earned CededPremiumsEarned	81000000	usd
CY2021	us-gaap	Ceded Premiums Earned CededPremiumsEarned	65000000	usd
CY2023	us-gaap	Reinsurance Costs And Recoveries Net ReinsuranceCostsAndRecoveriesNet	10000000	usd
CY2022	us-gaap	Reinsurance Costs And Recoveries Net ReinsuranceCostsAndRecoveriesNet	-13000000	usd
CY2021	us-gaap	Reinsurance Costs And Recoveries Net ReinsuranceCostsAndRecoveriesNet	-10000000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P4Y
CY2023	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	20800000	usd
CY2022	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	18200000	usd
CY2021	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	20200000	usd
CY2023	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	11400000	usd
CY2022	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	11000000	usd
CY2021	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	12800000	usd
CY2023Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	1600000	usd
CY2022Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	1300000	usd
CY2023Q4	us-gaap	Contract With Customer Refund Liability ContractWithCustomerRefundLiability	1000000	usd
CY2022Q4	us-gaap	Contract With Customer Refund Liability ContractWithCustomerRefundLiability	800000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	usd
CY2023Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	0	usd
CY2023Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	0	usd
CY2022Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	0	usd
CY2023Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	200000	usd
CY2022Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	1100000	usd
CY2023Q4	us-gaap	Capitalized Contract Cost Accumulated Amortization CapitalizedContractCostAccumulatedAmortization	5500000	usd
CY2022Q4	us-gaap	Capitalized Contract Cost Accumulated Amortization CapitalizedContractCostAccumulatedAmortization	4700000	usd
CY2023	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	900000	usd
CY2022	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2800000	usd
CY2023	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	4000	usd
CY2023	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-4000	usd
CY2022	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	8000	usd
CY2022	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	2500000	usd
CY2021	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	3900000	usd
CY2022Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5800000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	6000000	usd
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	10000000	usd
CY2023	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-2819000	usd
CY2022	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-4213000	usd
CY2021	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	893000	usd
CY2023	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	3879000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	5027000	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance	3693000	usd
CY2023	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	560000	usd
CY2022	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	614000	usd
CY2021	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	586000	usd
CY2023Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5300000	usd
CY2022Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	5800000	usd
CY2021Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	6000000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	usd
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	91000	usd
CY2023	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	-12000	usd
CY2022	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	usd
CY2021	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	91000	usd
CY2023	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
CY2022	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
CY2021	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	usd
CY2023	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
CY2022	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
CY2021	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	usd
CY2023Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	12000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	usd
CY2021Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	usd
CY2023	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	91109000	usd
CY2023	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-14265000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	86168000	usd
CY2022	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-2492000	usd
CY2021	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	236000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	61252000	usd
CY2022	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	24916000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	64061000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	18826000	usd
CY2021	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	45235000	usd
CY2023	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	0	usd
CY2023	us-gaap	Revenue Recognition Interest RevenueRecognitionInterest	<div style="text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company made certain accounting policy elections for its accrued interest receivables on the adoption date of Topic 326 as allowed: a) an election to present accrued interest receivable balances separately from the associated financial assets on the balance sheet, and b) an election not to measure an allowance for credit losses on accrued interest receivable amounts and instead write off uncollectible accrued interest amounts in a timely manner by reversing interest income. </span></div><div style="text-align:justify;text-indent:22.5pt"><span><br/></span></div><div style="text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">As a general policy, the Company writes off the accrued interest receivable balance when it receives a default notice or when the scheduled interest payment is not received, unless management determines that the default is temporary considering all of the relevant information. The Company believes that for the majority of its investment securities, writing off the uncollectible interest receivable balance within a year from the due date is considered timely. In all cases, the Company writes </span></div>off the accrued interest receivable immediately if management determines that it is not reasonably expected that the payment will be received. The Company's accrued interest receivable balances are included in accrued investment income receivables in its consolidated balance sheets.
CY2023Q4	us-gaap	Notes Receivable Fair Value Disclosure NotesReceivableFairValueDisclosure	9974000	usd
CY2022Q4	us-gaap	Notes Receivable Fair Value Disclosure NotesReceivableFairValueDisclosure	0	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1783000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	3246000	usd
CY2023	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-1463000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	863000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	71425000	usd
CY2022	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-70562000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	2306000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	6690000	usd
CY2021	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-4384000	usd
CY2023	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	76844000	usd
CY2021	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	381000	usd
CY2021	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-145000	usd
CY2023Q4	mcy	Debt Securities Trading Fair Value Maturity Allocated And Single Maturity Date Year One DebtSecuritiesTradingFairValueMaturityAllocatedAndSingleMaturityDateYearOne	306970000	usd
CY2023Q4	mcy	Debt Securities Trading Fair Value Maturity Allocated And Single Maturity Date After Year One Through Five DebtSecuritiesTradingFairValueMaturityAllocatedAndSingleMaturityDateAfterYearOneThroughFive	935982000	usd
CY2023Q4	mcy	Debt Securities Trading Fair Value Maturity Allocated And Single Maturity Date After Year5 Through10 DebtSecuritiesTradingFairValueMaturityAllocatedAndSingleMaturityDateAfterYear5Through10	888429000	usd
CY2023Q4	mcy	Debt Securities Trading Fair Value Maturity Allocated And Single Maturity Date After Year10 DebtSecuritiesTradingFairValueMaturityAllocatedAndSingleMaturityDateAfterYear10	2187955000	usd
CY2023Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	4319336000	usd
CY2023	us-gaap	Net Investment Income NetInvestmentIncome	241131000	usd
CY2022	us-gaap	Net Investment Income NetInvestmentIncome	174326000	usd
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	136124000	usd
CY2023	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6501000	usd
CY2022	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5970000	usd
CY2021	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6397000	usd
CY2023	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	234630000	usd
CY2022	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	168356000	usd
CY2021	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	129727000	usd
CY2023	mcy	Percentage Of Unadjusted Fair Value Obtained PercentageOfUnadjustedFairValueObtained	0.984
CY2023Q4	mcy	Three Private Equity Funds Using Nav ThreePrivateEquityFundsUsingNAV	79200000	usd
CY2022	mcy	Fair Value Assets Level1 To Level2 To Level3 Transfers Amount FairValueAssetsLevel1ToLevel2ToLevel3TransfersAmount	0	usd
CY2023	mcy	Fair Value Assets Level1 To Level2 To Level3 Transfers Amount FairValueAssetsLevel1ToLevel2ToLevel3TransfersAmount	0	usd
CY2023Q4	us-gaap	Notes Payable NotesPayable	573729000	usd
CY2022Q4	us-gaap	Notes Payable NotesPayable	398330000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	453529000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	489070000	usd
CY2023Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	302346000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	317628000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	151183000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	171442000	usd
CY2023	us-gaap	Depreciation Depreciation	33800000	usd
CY2022	us-gaap	Depreciation Depreciation	34300000	usd
CY2021	us-gaap	Depreciation Depreciation	32500000	usd
CY2023	us-gaap	Deferred Policy Acquisition Costs Text Block1 DeferredPolicyAcquisitionCostsTextBlock1	Deferred Policy Acquisition Costs<div style="margin-top:6pt;text-align:justify;text-indent:27pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Deferred policy acquisition costs were as follows:</span></div><div style="text-align:center"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:88.742%"><tr><td style="width:1.0%"></td><td style="width:54.254%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:13.232%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.623%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:13.232%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.623%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:13.236%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="15" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31,</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2022</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2021</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="15" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(Amounts in thousands)</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Balance, beginning of year</span></td><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">266,475 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">258,259 </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 style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">246,994 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Policy acquisition costs deferred</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">735,894 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">662,828 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">644,650 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Amortization</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(708,525)</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:10pt;font-weight:400;line-height:100%">(654,612)</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:10pt;font-weight:400;line-height:100%">(633,385)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Balance, end of year</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">293,844 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">266,475 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">258,259 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr></table></div>
CY2022Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	266475000	usd
CY2021Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	258259000	usd
CY2020Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	246994000	usd
CY2023	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	735894000	usd
CY2022	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	662828000	usd
CY2021	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	644650000	usd
CY2023	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	708525000	usd
CY2022	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	654612000	usd
CY2021	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	633385000	usd
CY2023Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	293844000	usd
CY2022Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	266475000	usd
CY2021Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	258259000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	11674000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	14747000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	15846000	usd
CY2023	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	1241000	usd
CY2022	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	1288000	usd
CY2021	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	719000	usd
CY2023	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	40000	usd
CY2022	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	54000	usd
CY2021	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	25000	usd
CY2023	us-gaap	Variable Lease Cost VariableLeaseCost	1100000	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	2184000	usd
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	1500000	usd
CY2023	us-gaap	Sublease Income SubleaseIncome	799000	usd
CY2022	us-gaap	Sublease Income SubleaseIncome	492000	usd
CY2021	us-gaap	Sublease Income SubleaseIncome	11000	usd
CY2023	us-gaap	Lease Cost LeaseCost	13256000	usd
CY2022	us-gaap	Lease Cost LeaseCost	17781000	usd
CY2021	us-gaap	Lease Cost LeaseCost	18079000	usd
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	14406000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	20183000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	14231000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	21924000	usd
CY2023Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	2996000	usd
CY2022Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	4233000	usd
CY2023Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2841000	usd
CY2022Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	3573000	usd
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y7M6D
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P2Y10M24D
CY2023Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P2Y6M
CY2022Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P3Y6M
CY2023Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.0437
CY2022Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.0284
CY2023Q4	us-gaap	Lessee Finance Lease Discount Rate LesseeFinanceLeaseDiscountRate	0.0137
CY2022Q4	us-gaap	Lessee Finance Lease Discount Rate LesseeFinanceLeaseDiscountRate	0.0129
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	14010000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	15815000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	16158000	usd
CY2023	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	41000	usd
CY2022	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	54000	usd
CY2021	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	25000	usd
CY2023	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1102000	usd
CY2022	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1504000	usd
CY2021	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	825000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	6587000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	4677000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	4904000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	1951000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	1115000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	7282000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	1449000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4039000	usd
CY2023Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2022Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	usd
CY2022	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1032000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	2351000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	405000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	1362000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	0	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	243000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	0	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	15277000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	2886000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	1046000	usd
CY2023Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	45000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	14231000	usd
CY2023Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2841000	usd
CY2023Q4	mcy	Lessee Operating Lease Lease Not Yet Commenced Amount LesseeOperatingLeaseLeaseNotYetCommencedAmount	3000000	usd
CY2023Q4	mcy	Notes Payable Principal NotesPayablePrincipal	575000000	usd
CY2022Q4	mcy	Notes Payable Principal NotesPayablePrincipal	400000000	usd
CY2023Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	1271000	usd
CY2022Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	1670000	usd
CY2023Q4	us-gaap	Notes Payable NotesPayable	573729000	usd
CY2022Q4	us-gaap	Notes Payable NotesPayable	398330000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	200000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	375000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	0	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	575000000	usd
CY2023	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	usd
CY2022	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	usd
CY2023Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	75962000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	67629000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	8333000	usd
CY2022Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	75962000	usd
CY2022Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	66750000	usd
CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	9212000	usd
CY2022	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	900000	usd
CY2022	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1000000	usd
CY2021	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1100000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	851000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	807000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	807000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	807000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	807000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	2854000	usd
CY2023Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	6933000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-3840000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-62355000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	37391000	usd
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	10523000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-93562000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	11349000	usd
CY2023	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	6683000	usd
CY2022	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	-155917000	usd
CY2021	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	48740000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-2958000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	784000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1542000	usd
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-633000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-2910000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	1088000	usd
CY2023	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-3591000	usd
CY2022	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-2126000	usd
CY2021	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	2630000	usd
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-6798000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-61571000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	38933000	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	9890000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-96472000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	12437000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3092000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-158043000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51370000	usd
CY2023	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	20880000	usd
CY2022	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-140850000	usd
CY2021	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	62854000	usd
CY2023	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	13640000	usd
CY2022	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	11864000	usd
CY2021	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	11577000	usd
CY2023	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1237000	usd
CY2022	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1364000	usd
CY2021	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1311000	usd
CY2023	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-3539000	usd
CY2022	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1597000	usd
CY2021	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2134000	usd
CY2023	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	639000	usd
CY2022	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	279000	usd
CY2021	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	843000	usd
CY2023	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-11000	usd
CY2022	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-2647000	usd
CY2021	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-1573000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3092000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-158043000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	51370000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	75394000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	67285000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	25340000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	21606000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	11262000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	11578000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Trading Securities DeferredTaxAssetsUnrealizedLossesOnTradingSecurities	166000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Unrealized Losses On Trading Securities DeferredTaxAssetsUnrealizedLossesOnTradingSecurities	22802000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	8743000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	6511000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	120905000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	129782000	usd
CY2023Q4	mcy	Deferred Tax Liabilities Acquisition Costs DeferredTaxLiabilitiesAcquisitionCosts	61707000	usd
CY2022Q4	mcy	Deferred Tax Liabilities Acquisition Costs DeferredTaxLiabilitiesAcquisitionCosts	55960000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	6801000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	11029000	usd
CY2023Q4	mcy	Deferred Tax Liabilities Undistributed Insurance Subsidiaries DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries	1511000	usd
CY2022Q4	mcy	Deferred Tax Liabilities Undistributed Insurance Subsidiaries DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries	1898000	usd
CY2023Q4	mcy	Deferred Tax Liabilities Tax Amortization In Excess Of Book Amortization DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization	8904000	usd
CY2022Q4	mcy	Deferred Tax Liabilities Tax Amortization In Excess Of Book Amortization DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization	7466000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	8969000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	10526000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	87892000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	86879000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	33013000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	42903000	usd
CY2023Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	19700000	usd
CY2022Q4	us-gaap	Operating Loss Carryforwards OperatingLossCarryforwards	5700000	usd
CY2023Q4	mcy	Operating Loss Carryforwards Subject To Expiration OperatingLossCarryforwardsSubjectToExpiration	2100000	usd
CY2023Q4	mcy	Operating Loss Carryforwards Not Subject To Expiration OperatingLossCarryforwardsNotSubjectToExpiration	17600000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-2100000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4380000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4380000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	2118000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	2262000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4380000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	3900000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	6600000	usd
CY2023	mcy	Income Tax Examination Penalties And Interest Benefit IncomeTaxExaminationPenaltiesAndInterestBenefit	1200000	usd
CY2022	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	400000	usd
CY2021	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	300000	usd
CY2023Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	2500000	usd
CY2022Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	3700000	usd
CY2023	us-gaap	Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense	<div style="margin-top:6pt;text-align:justify;text-indent:27pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The following table presents the activity in loss and loss adjustment expense reserves:</span></div><div style="margin-top:11pt"><table style="border-collapse:collapse;display:inline-table;margin-bottom:5pt;vertical-align:text-bottom;width:99.853%"><tr><td style="width:1.0%"></td><td style="width:59.222%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:11.637%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.532%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:11.637%"></td><td style="width:0.1%"></td><td style="width:0.1%"></td><td style="width:0.532%"></td><td style="width:0.1%"></td><td style="width:1.0%"></td><td style="width:11.640%"></td><td style="width:0.1%"></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="15" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Year Ended December 31,</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="3" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2023</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2022</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="border-bottom:1pt solid #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2021</span></td></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td colspan="15" style="border-top:1pt solid #000000;padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(Amounts in thousands)</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Gross reserves at January 1</span></td><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,584,910 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#cceeff;padding:0 1pt"></td><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,226,430 </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 style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,991,304 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 19pt;text-align:left;text-indent:-4.5pt;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Reinsurance recoverables on unpaid losses</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(25,323)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(41,379)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(54,461)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net reserves at January 1</span></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,559,587 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;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 #000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,185,051 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;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 #000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,936,843 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Incurred losses and loss adjustment expenses related to:</span></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:0 1pt"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 19pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;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:10pt;font-weight:400;line-height:100%">3,553,801 </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:10pt;font-weight:400;line-height:100%">3,314,938 </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:10pt;font-weight:400;line-height:100%">2,786,246 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 19pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;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:10pt;font-weight:400;line-height:100%">(35,948)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">47,281 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(26,091)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total incurred 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:10pt;font-weight:400;line-height:100%">3,517,853 </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:10pt;font-weight:400;line-height:100%">3,362,219 </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:10pt;font-weight:400;line-height:100%">2,760,155 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Loss and loss adjustment expense payments related to:</span></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 19pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;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:10pt;font-weight:400;line-height:100%">2,080,690 </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:10pt;font-weight:400;line-height:100%">1,862,006 </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:10pt;font-weight:400;line-height:100%">1,601,998 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 19pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;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:10pt;font-weight:400;line-height:100%">1,243,196 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,125,677 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">909,949 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Total payments</span></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">3,323,886 </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:10pt;font-weight:400;line-height:100%">2,987,683 </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:10pt;font-weight:400;line-height:100%">2,511,947 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Net reserves at December 31</span></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,753,554 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,559,587 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,185,051 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 19pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Reinsurance recoverables on unpaid losses</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">32,148 </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:10pt;font-weight:400;line-height:100%">25,323 </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:10pt;font-weight:400;line-height:100%">41,379 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">Gross reserves at December 31</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,785,702 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,584,910 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,226,430 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"></td></tr></table></div>
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	2584910000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	2226430000	usd
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1991304000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	25323000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	41379000	usd
CY2020Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	54461000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2559587000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2185051000	usd
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1936843000	usd
CY2023	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	3553801000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	3314938000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	2786246000	usd
CY2023	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-35948000	usd
CY2022	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	47281000	usd
CY2021	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	-26091000	usd
CY2023	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	3517853000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	3362219000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	2760155000	usd
CY2023	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	2080690000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1862006000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1601998000	usd
CY2023	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	1243196000	usd
CY2022	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	1125677000	usd
CY2021	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	909949000	usd
CY2023	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	3323886000	usd
CY2022	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2987683000	usd
CY2021	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2511947000	usd
CY2023Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2753554000	usd
CY2022Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2559587000	usd
CY2021Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	2185051000	usd
CY2023Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	32148000	usd
CY2022Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	25323000	usd
CY2021Q4	us-gaap	Reinsurance Recoverables On Unpaid Losses Gross ReinsuranceRecoverablesOnUnpaidLossesGross	41379000	usd
CY2023Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	2785702000	usd
CY2022Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	2584910000	usd
CY2021Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	2226430000	usd
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CY2023	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	3517900000	usd
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CY2023Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Fair Value SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue	5228520000	usd
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Files In Submission

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$MCY
MERCURY GENERAL CORP Stock $mcy

2024 Q1 Form 10-K Financial Statement

#000006499624000002 Filed on February 13, 2024

Income Statement

Balance Sheet

Cashflow Statement

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$MCY MERCURY GENERAL CORP Stock $mcy

2024 Q1 Form 10-K Financial Statement

#000006499624000002 Filed on February 13, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MCY
MERCURY GENERAL CORP Stock $mcy