$MCY
MERCURY GENERAL CORP Stock $mcy

$mcy Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000006499621000004 Filed on February 16, 2021

Income Statement

Concept	2020 Q4	2019 Q4	2019 Q3
Revenue	$1.072B	$988.0M	$987.3M
YoY Change	8.46%	20.99%	10.34%
Cost Of Revenue			$2.500M
YoY Change			13.64%
Gross Profit			$984.8M
YoY Change			10.33%
Gross Profit Margin			99.75%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$22.40M	$21.90M	$150.9M
YoY Change	2.28%	33.54%	6.04%
% of Gross Profit			15.32%
Operating Expenses	$860.2M	$955.3M	$902.2M
YoY Change	-9.95%	3.08%	9.98%
Operating Profit			$82.60M
YoY Change			14.22%
Interest Expense	-$4.300M	-$4.300M	$4.300M
YoY Change	0.0%	0.0%	0.0%
% of Operating Profit			5.21%
Other Income/Expense, Net
YoY Change
Pretax Income	$207.1M	$28.47M	$80.84M
YoY Change	627.6%	-124.87%	15.02%
Income Tax	$40.40M	-$3.200M	$11.56M
% Of Pretax Income	19.51%	-11.24%	14.3%
Net Earnings	$166.7M	$31.69M	$69.28M
YoY Change	426.2%	-138.7%	18.27%
Net Earnings / Revenue	15.56%	3.21%	7.02%
Basic Earnings Per Share	$3.01	$0.57	$1.25
Diluted Earnings Per Share	$3.01	$0.57	$1.25
COMMON SHARES
Basic Shares Outstanding	55.36M shares	55.35M shares	55.36M shares
Diluted Shares Outstanding			55.37M shares

Balance Sheet

Concept	2020 Q4	2019 Q4	2019 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$348.5M	$294.4M	$315.4M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets	$10.70M	$6.500M	$5.600M
YoY Change	64.62%	6.56%	-8.2%
LONG-TERM ASSETS
Property, Plant & Equipment	$178.9M	$169.0M	$168.3M
YoY Change	5.88%	10.43%	12.41%
Goodwill	$42.80M	$42.80M	$42.80M
YoY Change	0.0%	0.0%	0.0%
Intangibles	$11.32M	$10.64M	$11.90M
YoY Change	6.45%	-31.53%	-29.57%
Long-Term Investments	$4.729B	$4.312B	$4.218B
YoY Change	9.67%	14.44%	8.04%
Other Assets		$0.00	$0.00
YoY Change		-100.0%
Total Long-Term Assets	$6.318B	$5.883B	$5.868B
YoY Change	7.39%	8.38%	10.57%
TOTAL ASSETS
Total Short-Term Assets	$10.70M	$6.500M	$5.600M
Total Long-Term Assets	$6.318B	$5.883B	$5.868B
Total Assets	$6.328B	$5.889B	$5.873B
YoY Change	7.46%	8.38%	10.54%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$194.4M	$143.3M	$156.3M
YoY Change	35.66%	24.5%	12.77%
Accrued Expenses	$43.80M	$48.00M	$48.70M
YoY Change	-8.75%
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	$248.6M	$191.3M	$205.0M
YoY Change	29.95%	66.2%	47.91%
LONG-TERM LIABILITIES
Long-Term Debt	$372.5M	$372.1M	$372.0M
YoY Change	0.11%	0.11%	0.11%
Other Long-Term Liabilities	$236.1M	$221.4M	$233.4M
YoY Change	6.64%	-16.01%	-2.99%
Total Long-Term Liabilities	$608.6M	$593.5M	$605.4M
YoY Change	2.54%	-6.58%	-1.11%
TOTAL LIABILITIES
Total Short-Term Liabilities	$248.6M	$191.3M	$205.0M
Total Long-Term Liabilities	$608.6M	$593.5M	$605.4M
Total Liabilities	$4.296B	$4.090B	$4.071B
YoY Change	5.04%	7.17%	13.74%
SHAREHOLDERS EQUITY
Retained Earnings	$1.934B	$1.701B	$1.704B
YoY Change	13.7%	11.91%	4.13%
Common Stock	$98.97M	$98.83M	$98.68M
YoY Change	0.14%	0.82%	0.73%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.033B	$1.800B	$1.803B
YoY Change
Total Liabilities & Shareholders Equity	$6.328B	$5.889B	$5.873B
YoY Change	7.46%	8.38%	10.54%

Cashflow Statement

Concept	2020 Q4	2019 Q4	2019 Q3
OPERATING ACTIVITIES
Net Income	$166.7M	$31.69M	$69.28M
YoY Change	426.2%	-138.7%	18.27%
Depreciation, Depletion And Amortization	$22.40M	$21.90M	$150.9M
YoY Change	2.28%	33.54%	6.04%
Cash From Operating Activities	$162.3M	$106.1M	$148.0M
YoY Change	52.97%	82.3%	4.89%
INVESTING ACTIVITIES
Capital Expenditures	-$10.20M	-$8.300M	-$10.90M
YoY Change	22.89%	12.16%	45.33%
Acquisitions
YoY Change
Other Investing Activities	-$90.20M	-$84.00M	-$27.20M
YoY Change	7.38%	-330.77%	-66.63%
Cash From Investing Activities	-$100.4M	-$92.30M	-$38.20M
YoY Change	8.78%	-417.18%	-57.03%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-35.60M	-34.80M	-34.70M
YoY Change	2.3%	0.29%	1.46%
NET CHANGE
Cash From Operating Activities	162.3M	106.1M	148.0M
Cash From Investing Activities	-100.4M	-92.30M	-38.20M
Cash From Financing Activities	-35.60M	-34.80M	-34.70M
Net Change In Cash	26.30M	-21.00M	75.10M
YoY Change	-225.24%	-139.92%	317.22%
FREE CASH FLOW
Cash From Operating Activities	$162.3M	$106.1M	$148.0M
Capital Expenditures	-$10.20M	-$8.300M	-$10.90M
Free Cash Flow	$172.5M	$114.4M	$158.9M
YoY Change	50.79%	74.39%	6.93%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
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CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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CY2020	dei	Document Type DocumentType	10-K
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CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-12257
CY2020	dei	Entity Registrant Name EntityRegistrantName	MERCURY GENERAL CORPORATION
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	CA
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	95-2211612
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	4484 Wilshire Boulevard
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Los Angeles,
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	90010
CY2020	dei	City Area Code CityAreaCode	323
CY2020	dei	Local Phone Number LocalPhoneNumber	937-1060
CY2020	dei	Security12b Title Security12bTitle	Common Stock
CY2020	dei	Trading Symbol TradingSymbol	MCY
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
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CY2020	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	-30127000	USD
CY2019	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	-142314000	USD
CY2018	us-gaap	Increase Decrease In Reinsurance Recoverable IncreaseDecreaseInReinsuranceRecoverable	164739000	USD
CY2020	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-31236000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-72545000	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	13898000	USD
CY2020	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	13828000	USD
CY2019	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	18035000	USD
CY2018	us-gaap	Increase Decrease In Deferred Policy Acquisition Costs IncreaseDecreaseInDeferredPolicyAcquisitionCosts	16980000	USD
CY2020	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	70049000	USD
CY2019	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	91843000	USD
CY2018	us-gaap	Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve IncreaseDecreaseInLiabilityForClaimsAndClaimsAdjustmentExpenseReserve	318799000	USD
CY2020	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	50326000	USD
CY2019	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	119366000	USD
CY2018	us-gaap	Increase Decrease In Unearned Premiums IncreaseDecreaseInUnearnedPremiums	134254000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	51988000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	26493000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	6586000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	142000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	123000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	145000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	14291000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-27163000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	13663000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	605616000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	519678000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	383434000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	878213000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	491795000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	706224000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	168087000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	136560000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	189306000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	250878000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	316860000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	334626000	USD
CY2020	mcy	Paymentsto Acquire Equity Securities Fvni PaymentstoAcquireEquitySecuritiesFVNI	1230785000	USD
CY2019	mcy	Paymentsto Acquire Equity Securities Fvni PaymentstoAcquireEquitySecuritiesFVNI	1174759000	USD
CY2018	mcy	Paymentsto Acquire Equity Securities Fvni PaymentstoAcquireEquitySecuritiesFVNI	1026827000	USD
CY2020	mcy	Proceedsfrom Saleof Equity Securities Fvni ProceedsfromSaleofEquitySecuritiesFVNI	1174540000	USD
CY2019	mcy	Proceedsfrom Saleof Equity Securities Fvni ProceedsfromSaleofEquitySecuritiesFVNI	1088701000	USD
CY2018	mcy	Proceedsfrom Saleof Equity Securities Fvni ProceedsfromSaleofEquitySecuritiesFVNI	954755000	USD
CY2020	mcy	Proceeds From Calls Of Available For Sale Securities ProceedsFromCallsOfAvailableForSaleSecurities	3880000	USD
CY2019	mcy	Proceeds From Calls Of Available For Sale Securities ProceedsFromCallsOfAvailableForSaleSecurities	0	USD
CY2018	mcy	Proceeds From Calls Of Available For Sale Securities ProceedsFromCallsOfAvailableForSaleSecurities	0	USD
CY2020	us-gaap	Increase Decrease In Broker Dealer Related Receivables Payables Net IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet	-873000	USD
CY2019	us-gaap	Increase Decrease In Broker Dealer Related Receivables Payables Net IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet	2536000	USD
CY2018	us-gaap	Increase Decrease In Broker Dealer Related Receivables Payables Net IncreaseDecreaseInBrokerDealerRelatedReceivablesPayablesNet	-4035000	USD
CY2020	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-118830000	USD
CY2019	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	240391000	USD
CY2018	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	-45747000	USD
CY2020	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	39953000	USD
CY2019	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	40088000	USD
CY2018	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	27959000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-20577000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-6247000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-10105000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-411286000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-401201000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-222436000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	139640000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	139071000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	138478000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	701000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	358000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	609000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	0	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-140249000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-138370000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-138120000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	54081000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-19893000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	22878000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	294398000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	314291000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	291413000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	348479000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	294398000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	314291000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	16599000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	16586000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	16586000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	52659000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-14564000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-10989000	USD
CY2020	mcy	Number Of Companies NumberOfCompanies	14	Subsidiary
CY2020Q4	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	11	State
CY2020	mcy	Percentage Of Direct Premiums Written As Private Passenger Automobile Lines Of Insurance PercentageOfDirectPremiumsWrittenAsPrivatePassengerAutomobileLinesOfInsurance	0.70
CY2020	mcy	Percentage Of Private Passenger Automobile Premiums Written In California PercentageOfPrivatePassengerAutomobilePremiumsWrittenInCalifornia	0.88
CY2019	mcy	Percentage Of Private Passenger Automobile Premiums Written In California PercentageOfPrivatePassengerAutomobilePremiumsWrittenInCalifornia	0.88
CY2018	mcy	Percentage Of Private Passenger Automobile Premiums Written In California PercentageOfPrivatePassengerAutomobilePremiumsWrittenInCalifornia	0.87
CY2020	us-gaap	Use Of Estimates UseOfEstimates	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 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.
CY2020	mcy	Percentage By Which Dividend Income On Non Redeemable Preferred Stock Partnership Common Stock Is Partially Tax Sheltered PercentageByWhichDividendIncomeOnNonRedeemablePreferredStockPartnershipCommonStockIsPartiallyTaxSheltered	0.50
CY2020Q4	mcy	Security Deposits By Insurance Companies SecurityDepositsByInsuranceCompanies	15000000	USD
CY2019Q4	mcy	Security Deposits By Insurance Companies SecurityDepositsByInsuranceCompanies	16000000	USD
CY2020	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	627800000	USD
CY2019	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	602100000	USD
CY2018	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	572200000	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	37700000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	42200000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	40900000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2019	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020	us-gaap	Premiums Written Net PremiumsWrittenNet	3610000000	USD
CY2019	us-gaap	Premiums Written Net PremiumsWrittenNet	3730000000	USD
CY2018	us-gaap	Premiums Written Net PremiumsWrittenNet	3500000000	USD
CY2020	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	128000000	USD
CY2020Q4	us-gaap	Contract With Customer Refund Liability ContractWithCustomerRefundLiability	900000	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Gross ReinsuranceRecoverablesGross	31000000	USD
CY2020	us-gaap	Reinsurance Retention Policy Reinsured Risk Percentage ReinsuranceRetentionPolicyReinsuredRiskPercentage	0.71
CY2020	us-gaap	Reinsurance Retention Policy Excess Retention Amount Reinsured ReinsuranceRetentionPolicyExcessRetentionAmountReinsured	717000000	USD
CY2020	us-gaap	Reinsurance Retention Policy Amount Retained ReinsuranceRetentionPolicyAmountRetained	40000000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	56000000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	57000000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	49000000	USD
CY2020	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	28000000	USD
CY2019	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	71000000	USD
CY2018	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	-257000000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P4Y
CY2020	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	18000000.0	USD
CY2019	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	16300000	USD
CY2018	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	16000000.0	USD
CY2020	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	11800000	USD
CY2019	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	10500000	USD
CY2018	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	10500000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	1200000	USD
CY2020Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	1200000	USD
CY2019Q4	us-gaap	Contract With Customer Refund Liability ContractWithCustomerRefundLiability	700000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	4800000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	4400000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Accumulated Amortization CapitalizedContractCostAccumulatedAmortization	2100000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Accumulated Amortization CapitalizedContractCostAccumulatedAmortization	300000	USD
CY2020	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	1800000	USD
CY2019	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	300000	USD
CY2019Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	1445000	USD
CY2018Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	1458000	USD
CY2017Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	1258000	USD
CY2020	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-10294000	USD
CY2019	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-6162000	USD
CY2018	us-gaap	Premium Receivable Credit Loss Expense Reversal PremiumReceivableCreditLossExpenseReversal	-6463000	USD
CY2020	mcy	Premium Receivable Allowancefor Credit Loss Writeoff PremiumReceivableAllowanceforCreditLossWriteoff	4406000	USD
CY2019	mcy	Premium Receivable Allowancefor Credit Loss Writeoff PremiumReceivableAllowanceforCreditLossWriteoff	7000000	USD
CY2018	mcy	Premium Receivable Allowancefor Credit Loss Writeoff PremiumReceivableAllowanceforCreditLossWriteoff	6908000	USD
CY2020	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	812000	USD
CY2019	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	825000	USD
CY2018	us-gaap	Premiums Receivable Allowance For Doubtful Accounts Recoveries PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries	645000	USD
CY2020Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	10000000	USD
CY2019Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	1445000	USD
CY2018Q4	us-gaap	Premiums Receivable Allowance For Doubtful Accounts PremiumsReceivableAllowanceForDoubtfulAccounts	1458000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	USD
CY2018Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	USD
CY2017Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	USD
CY2020	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	-68000	USD
CY2019	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	USD
CY2018	us-gaap	Reinsurance Recoverable Credit Loss Expense Reversal ReinsuranceRecoverableCreditLossExpenseReversal	0	USD
CY2020	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2019	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2018	us-gaap	Reinsurance Loss On Uncollectible Accounts In Period Amount ReinsuranceLossOnUncollectibleAccountsInPeriodAmount	0	USD
CY2020	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	USD
CY2019	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	USD
CY2018	us-gaap	Reinsurance Recoverable Allowance For Credit Loss Recovery ReinsuranceRecoverableAllowanceForCreditLossRecovery	0	USD
CY2020Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	91000	USD
CY2019Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	USD
CY2018Q4	us-gaap	Reinsurance Recoverables Allowance ReinsuranceRecoverablesAllowance	0	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	1884000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	4296000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-2412000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	2413000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	1066000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	1347000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	549000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	3563000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain Loss DebtSecuritiesAvailableForSaleRealizedGainLoss	-3014000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	75591000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	80134000	USD
CY2020	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-4543000	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	47411000	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	28089000	USD
CY2019	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	19322000	USD
CY2018	us-gaap	Equity Securities Fv Ni Realized Gain EquitySecuritiesFvNiRealizedGain	43420000	USD
CY2018	us-gaap	Equity Securities Fv Ni Realized Loss EquitySecuritiesFvNiRealizedLoss	45607000	USD
CY2018	us-gaap	Equity Securities Fv Ni Realized Gain Loss EquitySecuritiesFvNiRealizedGainLoss	-2187000	USD
CY2020	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	146000	USD
CY2020	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	2438000	USD
CY2020	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-2292000	USD
CY2019	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	177000	USD
CY2019	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	2133000	USD
CY2019	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-1956000	USD
CY2018	mcy	Shortterm Investments Realized Gain ShorttermInvestmentsRealizedGain	61000	USD
CY2018	mcy	Shortterm Investments Realized Loss ShorttermInvestmentsRealizedLoss	2429000	USD
CY2018	mcy	Shortterm Investments Realized Gain Loss ShorttermInvestmentsRealizedGainLoss	-2368000	USD
CY2020Q4	mcy	Trading Securities Debt Maturities Within One Year Fair Value TradingSecuritiesDebtMaturitiesWithinOneYearFairValue	246708000	USD
CY2020Q4	mcy	Trading Securities Debt Maturities After One Through Five Years Fair Value TradingSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	693068000	USD
CY2020Q4	mcy	Trading Securities Debt Maturities After Five Through Ten Years Fair Value TradingSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	540052000	USD
CY2020Q4	mcy	Trading Securities Debt Maturities After Ten Years Fair Value TradingSecuritiesDebtMaturitiesAfterTenYearsFairValue	2069982000	USD
CY2020Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	3549810000	USD
CY2020	us-gaap	Net Investment Income NetInvestmentIncome	140586000	USD
CY2019	us-gaap	Net Investment Income NetInvestmentIncome	146868000	USD
CY2018	us-gaap	Net Investment Income NetInvestmentIncome	141483000	USD
CY2020	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5728000	USD
CY2019	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5605000	USD
CY2018	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	5645000	USD
CY2020	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	134858000	USD
CY2019	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	141263000	USD
CY2018	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	135838000	USD
CY2020	mcy	Percentage Of Unadjusted Fair Value Obtained PercentageOfUnadjustedFairValueObtained	0.983
CY2020Q4	mcy	Two Private Equity Funds Using Nav TwoPrivateEquityFundsUsingNAV	78200000	USD
CY2020Q4	mcy	One Private Equity Fund Using Nav OnePrivateEquityFundUsingNAV	1200000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	464946000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	481046000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	286023000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	312060000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	178923000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	168986000	USD
CY2020	us-gaap	Depreciation Depreciation	28000000.0	USD
CY2019	us-gaap	Depreciation Depreciation	23200000	USD
CY2018	us-gaap	Depreciation Depreciation	19900000	USD
CY2017Q3	mcy	Numberof Acres NumberofAcres	6	acre
CY2017Q3	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	12200000	USD
CY2017Q3	mcy	Promissory Note Receivedin Sale Of Property Planand Equipment PromissoryNoteReceivedinSaleOfPropertyPlanandEquipment	5700000	USD
CY2017Q3	mcy	Stated Interest Rate On Promissory Note StatedInterestRateOnPromissoryNote	0.035
CY2020	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="margin-bottom:5pt;margin-top:11pt;text-align:center"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:88.742%"><tr><td style="width:1.0%"/><td style="width:54.254%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:13.232%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.623%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:13.232%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.623%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:13.236%"/><td style="width:0.1%"/></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%">2020</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><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%">2019</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><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%">2018</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%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">233,166 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">215,131 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td 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%">198,151 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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%">641,616 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">620,120 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">589,144 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align: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%">(627,788)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(602,085)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(572,164)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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%">246,994 </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 colspan="3" style="background-color:#ffffff;padding:0 1pt"/><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%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">233,166 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">215,131 </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"/></tr></table></div>
CY2019Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	233166000	USD
CY2018Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	215131000	USD
CY2017Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	198151000	USD
CY2020	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	641616000	USD
CY2019	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	620120000	USD
CY2018	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Additions DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAdditions	589144000	USD
CY2020	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	627788000	USD
CY2019	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	602085000	USD
CY2018	us-gaap	Deferred Policy Acquisition Costs And Present Value Of Future Profits Amortization1 DeferredPolicyAcquisitionCostsAndPresentValueOfFutureProfitsAmortization1	572164000	USD
CY2020Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	246994000	USD
CY2019Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	233166000	USD
CY2018Q4	us-gaap	Deferred Policy Acquisition Costs And Value Of Business Acquired DeferredPolicyAcquisitionCostsAndValueOfBusinessAcquired	215131000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	15814000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	15146000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	338000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	0	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	13000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	0	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	1697000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	2196000	USD
CY2020	us-gaap	Lease Cost LeaseCost	17862000	USD
CY2019	us-gaap	Lease Cost LeaseCost	17342000	USD
CY2018	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	14900000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	40554000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	44909000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	43825000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	47996000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	3107000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	0	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2836000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	0	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P3Y9M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P4Y4M24D
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P5Y1M6D
CY2020Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.0282
CY2019Q4	us-gaap	Lessee Operating Lease Discount Rate LesseeOperatingLeaseDiscountRate	0.0302
CY2020Q4	us-gaap	Lessee Finance Lease Discount Rate LesseeFinanceLeaseDiscountRate	0.0082
CY2019Q4	us-gaap	Lessee Finance Lease Discount Rate LesseeFinanceLeaseDiscountRate	0
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	15539000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	14289000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	13000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	0	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	609000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	8673000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	15372000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	3047000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	15370000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	622000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	12739000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	622000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	8095000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	622000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4388000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	622000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2832000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	398000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	2985000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	0	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	46409000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	2886000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	2584000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	50000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	43825000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2836000	USD
CY2020Q4	mcy	Lessee Operating Lease Not Yet Commenced Amount LesseeOperatingLeaseNotYetCommencedAmount	5000000	USD
CY2020Q4	mcy	Notes Payable Principal NotesPayablePrincipal	375000000	USD
CY2019Q4	mcy	Notes Payable Principal NotesPayablePrincipal	375000000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	2468000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium And Debt Issuance Costs Net DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet	2867000	USD
CY2020Q4	us-gaap	Notes Payable NotesPayable	372532000	USD
CY2019Q4	us-gaap	Notes Payable NotesPayable	372133000	USD
CY2017Q1	us-gaap	Repayments Of Debt RepaymentsOfDebt	320000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	375000000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	375000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	0	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	77000	USD
CY2020	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	USD
CY2019	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2019Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2020Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	75962000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	64640000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	11322000	USD
CY2019Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	74313000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	63677000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	10636000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1000000.0	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5100000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5500000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	1067000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	1043000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	879000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	851000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	807000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense After Year Five FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive	5275000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	9922000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	69554000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	18109000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	14190000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	12340000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	40413000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-39244000	USD
CY2020	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	81894000	USD
CY2019	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	58522000	USD
CY2018	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	-25054000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1172000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-1430000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	1982000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	828000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	890000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-1815000	USD
CY2020	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	2000000	USD
CY2019	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	-540000	USD
CY2018	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	167000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	70726000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16679000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	16172000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	13168000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	41303000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-41059000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	83894000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	57982000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-24887000	USD
CY2018	mcy	Tax Cutsand Jobs Act Changein Tax Rate Deferred Tax Liability Income Tax Benefit TaxCutsandJobsActChangeinTaxRateDeferredTaxLiabilityIncomeTaxBenefit	8600000	USD
CY2020	mcy	Tax Cutsand Jobs Act Changein Tax Rate Deferred Tax Liability Income Tax Benefit TaxCutsandJobsActChangeinTaxRateDeferredTaxLiabilityIncomeTaxBenefit	5600000	USD
CY2019	mcy	Tax Cutsand Jobs Act Changein Tax Rate Deferred Tax Liability Income Tax Benefit TaxCutsandJobsActChangeinTaxRateDeferredTaxLiabilityIncomeTaxBenefit	6700000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	96285000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	79394000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-6429000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	12270000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	12909000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	13507000	USD
CY2020	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1335000	USD
CY2019	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1276000	USD
CY2018	us-gaap	Income Tax Reconciliation Deductions Dividends IncomeTaxReconciliationDeductionsDividends	1082000	USD
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1678000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-869000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	439000	USD
CY2020	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	983000	USD
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	526000	USD
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	390000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Contingencies Domestic IncomeTaxReconciliationTaxContingenciesDomestic	0	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Contingencies Domestic IncomeTaxReconciliationTaxContingenciesDomestic	-2588000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Contingencies Domestic IncomeTaxReconciliationTaxContingenciesDomestic	0	USD
CY2020	mcy	Effective Income Tax Rate Reconciliation Reductionto Alternative Minimum Tax Credit Amount EffectiveIncomeTaxRateReconciliationReductiontoAlternativeMinimumTaxCreditAmount	0	USD
CY2019	mcy	Effective Income Tax Rate Reconciliation Reductionto Alternative Minimum Tax Credit Amount EffectiveIncomeTaxRateReconciliationReductiontoAlternativeMinimumTaxCreditAmount	0	USD
CY2018	mcy	Effective Income Tax Rate Reconciliation Reductionto Alternative Minimum Tax Credit Amount EffectiveIncomeTaxRateReconciliationReductiontoAlternativeMinimumTaxCreditAmount	-4088000	USD
CY2020	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-1447000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-4296000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-610000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	83894000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	57982000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-24887000	USD
CY2020	mcy	Effective Income Tax Rate Reconciliation Reductionto Alternative Minimum Tax Credit Percent EffectiveIncomeTaxRateReconciliationReductiontoAlternativeMinimumTaxCreditPercent	0.066
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	61067000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	8105000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Unearned Premiums Reserve DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsUnearnedPremiumsReserve	58448000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	15090000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsLossReserves	12769000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Impairment Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsImpairmentLosses	293000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Impairment Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsImpairmentLosses	314000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	14432000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Reserves DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsReserves	8099000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	6401000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	3348000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	97283000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	82978000	USD
CY2020Q4	mcy	Deferred Tax Liabilities Acquisition Costs DeferredTaxLiabilitiesAcquisitionCosts	51869000	USD
CY2019Q4	mcy	Deferred Tax Liabilities Acquisition Costs DeferredTaxLiabilitiesAcquisitionCosts	48964000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	56531000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Unrealized Gains On Trading Securities DeferredTaxLiabilitiesUnrealizedGainsOnTradingSecurities	41273000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	12632000	USD
CY2020Q4	mcy	Deferred Tax Liabilities Undistributed Insurance Subsidiaries DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries	3382000	USD
CY2019Q4	mcy	Deferred Tax Liabilities Undistributed Insurance Subsidiaries DeferredTaxLiabilitiesUndistributedInsuranceSubsidiaries	2855000	USD
CY2020Q4	mcy	Deferred Tax Liabilities Tax Amortization In Excess Of Book Amortization DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization	4666000	USD
CY2019Q4	mcy	Deferred Tax Liabilities Tax Amortization In Excess Of Book Amortization DeferredTaxLiabilitiesTaxAmortizationInExcessOfBookAmortization	3264000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	9335000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	6481000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	138415000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	110942000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	41132000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	27964000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Period Increase Decrease UnrecognizedTaxBenefitsPeriodIncreaseDecrease	-1400000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	6051000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	10615000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1417000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	4564000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	4634000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	6051000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	6200000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	7200000	USD
CY2020	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	200000	USD
CY2019	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	-100000	USD
CY2018	us-gaap	Income Tax Examination Penalties And Interest Expense IncomeTaxExaminationPenaltiesAndInterestExpense	500000	USD
CY2020Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	3100000	USD
CY2019Q4	us-gaap	Income Tax Examination Penalties And Interest Accrued IncomeTaxExaminationPenaltiesAndInterestAccrued	2800000	USD
CY2020	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-bottom:5pt;margin-top:11pt"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.853%"><tr><td style="width:1.0%"/><td style="width:59.222%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.637%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.532%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.637%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:0.532%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:11.640%"/><td style="width:0.1%"/></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%">2020</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><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%">2019</span></td><td colspan="3" style="border-top:1pt solid #000000;padding:0 1pt"/><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%">2018</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%">$</span></td><td style="background-color:#cceeff;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,921,255 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">1,829,412 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td 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%">1,510,613 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 19pt;text-align:left;text-indent:-4.5pt;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;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%">(76,100)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(180,859)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">(64,001)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:justify;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%"> Cumulative effect of adopting ASU 2016-13 </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%">149 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 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:9pt;font-weight:400;line-height:100%">Reinsurance recoverables on unpaid losses, as adjusted</span></td><td colspan="2" style="background-color:#ffffff;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%">(75,951)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #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%">(180,859)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #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%">(64,001)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:100%">Net reserves at January 1, as adjusted</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%">1,845,304 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #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%">1,648,553 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #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%">1,446,612 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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 colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000;padding:0 1pt"/></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%">2,372,364 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,696,230 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,483,693 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 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%">22,979 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">9,794 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">93,096 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align: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%">2,395,343 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,706,024 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,576,789 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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 colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 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%">1,366,661 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,651,550 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,543,828 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 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%">937,142 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">857,872 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">831,020 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align: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%">2,303,803 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,509,422 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">2,374,848 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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%">1,936,844 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,845,155 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,648,553 </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 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%">54,460 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">76,100 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">180,859 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align: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%">1,991,304 </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 colspan="3" style="background-color:#ffffff;padding:0 1pt"/><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%">$</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">1,921,255 </span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:100%">$</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%">1,829,412 </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"/></tr></table></div>
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1921255000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1829412000	USD
CY2017Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1510613000	USD
CY2019Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	76100000	USD
CY2018Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	180859000	USD
CY2017Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	64001000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1648553000	USD
CY2017Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1446612000	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	2372364000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	2696230000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense	2483693000	USD
CY2020	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	22979000	USD
CY2019	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	9794000	USD
CY2018	us-gaap	Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense	93096000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	2395343000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	2706024000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1	2576789000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1366661000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1651550000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1	1543828000	USD
CY2020	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	937142000	USD
CY2019	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	857872000	USD
CY2018	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1 LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1	831020000	USD
CY2020	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2303803000	USD
CY2019	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2509422000	USD
CY2018	us-gaap	Payments For Losses And Loss Adjustment Expense PaymentsForLossesAndLossAdjustmentExpense	2374848000	USD
CY2020Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1936844000	USD
CY2019Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1845155000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1648553000	USD
CY2020Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	54460000	USD
CY2019Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	76100000	USD
CY2018Q4	mcy	Reissuance Recoverable ReissuanceRecoverable	180859000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1991304000	USD
CY2019Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1921255000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1829412000	USD
CY2018Q4	us-gaap	Liability For Catastrophe Claims Carrying Amount LiabilityForCatastropheClaimsCarryingAmount	289000000	USD
CY2020Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Allocated Claim Adjustment Expense Net ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndAllocatedClaimAdjustmentExpenseNet	1820077000	USD
CY2020Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	54460000	USD
CY2020Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claim Adjustment Expense Other Reconciling Item ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseOtherReconcilingItem	676000	USD
CY2020Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claims Adjustment Expense Accumulated Unallocated Claim Adjustment Expense ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseAccumulatedUnallocatedClaimAdjustmentExpense	116091000	USD
CY2020Q4	us-gaap	Shortduration Insurance Contracts Liability For Unpaid Claims And Claim Adjustment Expense Aggregate Reconciling Items ShortdurationInsuranceContractsLiabilityForUnpaidClaimsAndClaimAdjustmentExpenseAggregateReconcilingItems	116767000	USD
CY2020Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1991304000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	139640000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	139071000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	138478000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.5225
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.5125
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.5025
CY2020Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	222000000	USD
CY2020	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	121000000	USD
CY2019	us-gaap	Payments Of Ordinary Dividends PaymentsOfOrdinaryDividends	114000000	USD
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CY2019	us-gaap	Deferred Compensation Arrangement With Individual Contributions By Employer DeferredCompensationArrangementWithIndividualContributionsByEmployer	9900000	USD
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CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	123000	USD
CY2020	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	0	USD
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CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period1 ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1	P4Y
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CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	67500	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	43.01
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	0	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	0
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CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	43.01
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P7Y1M6D
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	621000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	32500	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	43.01
CY2020	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P7Y1M6D
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	299000	USD
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CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	42000	USD
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CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55358000	shares
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CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55351000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	5.78
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-5728000	USD
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CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	374607000	USD
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55358000	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	6.77
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	320087000	USD
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55360000	shares
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.78
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CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55335000	shares
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.10
CY2020Q2	mcy	Catastrophe Claims Maximum Exposure Carrying Amount CatastropheClaimsMaximumExposureCarryingAmount	78000000.0	USD
CY2020	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	128000000	USD
CY2020	us-gaap	Increase Decrease In Unearned Premiums Net IncreaseDecreaseInUnearnedPremiumsNet	128000000	USD
CY2020Q1	us-gaap	Premiums Earned Net PremiumsEarnedNet	922574000	USD
CY2020Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	811897000	USD
CY2020Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	899304000	USD
CY2020Q4	us-gaap	Premiums Earned Net PremiumsEarnedNet	921860000	USD
CY2020Q1	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	-240990000	USD
CY2020Q2	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	166829000	USD
CY2020Q3	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	58865000	USD
CY2020Q4	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	87968000	USD
CY2020Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-180705000	USD
CY2020Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	285466000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	146631000	USD
CY2020Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	207110000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	-139204000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	228211000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	118857000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	166743000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-2.51
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.12
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.15
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.01
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-2.51
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.15
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.12
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.01
CY2020Q1	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6300
CY2020Q2	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6300
CY2020Q3	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6300
CY2020Q4	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6325
CY2019Q1	us-gaap	Premiums Earned Net PremiumsEarnedNet	870245000	USD
CY2019Q2	us-gaap	Premiums Earned Net PremiumsEarnedNet	888776000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	915012000	USD
CY2019Q4	us-gaap	Premiums Earned Net PremiumsEarnedNet	925384000	USD
CY2019Q1	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	104227000	USD
CY2019Q2	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	50281000	USD
CY2019Q3	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	24021000	USD
CY2019Q4	us-gaap	Fair Value Option Changes In Fair Value Gain Loss1 FairValueOptionChangesInFairValueGainLoss1	18173000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	167169000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	101595000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	80840000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	28465000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	135867000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	83250000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69282000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	31688000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.46
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.50
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.25
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.57
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.45
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.50
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.25
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.57
CY2019Q1	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6275
CY2019Q2	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6275
CY2019Q3	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6275
CY2019Q4	us-gaap	Dividends Payable Amount Per Share DividendsPayableAmountPerShare	0.6300
CY2020	mcy	Number Of Companies NumberOfCompanies	14	Subsidiary
CY2020Q4	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	11	State
CY2020	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	1	segment
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	3555600000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	3599400000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	3368400000	USD
CY2020	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	2395300000	USD
CY2019	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	2706000000.0	USD
CY2018	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	2576800000	USD
CY2020	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	913700000	USD
CY2019	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	871400000	USD
CY2018	us-gaap	Other Underwriting Expense OtherUnderwritingExpense	816800000	USD
CY2020	us-gaap	Underwriting Income Loss UnderwritingIncomeLoss	246600000	USD
CY2019	us-gaap	Underwriting Income Loss UnderwritingIncomeLoss	22000000.0	USD
CY2018	us-gaap	Underwriting Income Loss UnderwritingIncomeLoss	-25200000	USD
CY2020	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	134900000	USD
CY2019	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	141300000	USD
CY2018	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	135800000	USD
CY2020	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	85700000	USD
CY2019	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	222800000	USD
CY2018	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-133500000	USD
CY2020	us-gaap	Other Income OtherIncome	8300000	USD
CY2019	us-gaap	Other Income OtherIncome	9000000.0	USD
CY2018	us-gaap	Other Income OtherIncome	9300000	USD
CY2020	us-gaap	Interest Expense InterestExpense	17000000.0	USD
CY2019	us-gaap	Interest Expense InterestExpense	17000000.0	USD
CY2018	us-gaap	Interest Expense InterestExpense	17000000.0	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	458500000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	378100000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-30600000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	374600000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	320100000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-5700000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	3555600000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	3599400000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	3368400000	USD
CY2020	us-gaap	Direct Premiums Written DirectPremiumsWritten	3654200000	USD
CY2019	us-gaap	Direct Premiums Written DirectPremiumsWritten	3774600000	USD
CY2018	us-gaap	Direct Premiums Written DirectPremiumsWritten	3550900000	USD
CY2020Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	4460115000	USD
CY2020Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Fair Value SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue	4729270000	USD
CY2020Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Carrying Amount SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCarryingAmount	4729270000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Cost SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost	4115618000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Fair Value SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesFairValue	4312161000	USD
CY2019Q4	us-gaap	Summary Of Investments Other Than Investments In Related Parties Carrying Amount SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCarryingAmount	4312161000	USD
CY2020	mcy	Proceedsfrom Subsidiary Entity Dividendsor Distributions ProceedsfromSubsidiaryEntityDividendsorDistributions	12100000	USD
CY2019	mcy	Proceedsfrom Subsidiary Entity Dividendsor Distributions ProceedsfromSubsidiaryEntityDividendsorDistributions	5200000	USD
CY2020	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	121000000	USD
CY2019	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	114431433	USD
CY2018	us-gaap	Proceeds From Dividends Received ProceedsFromDividendsReceived	135000000	USD
CY2017Q1	us-gaap	Repayments Of Debt RepaymentsOfDebt	320000000	USD
CY2020	us-gaap	Direct Premiums Earned DirectPremiumsEarned	3603780000	USD
CY2019	us-gaap	Direct Premiums Earned DirectPremiumsEarned	3655233000	USD
CY2018	us-gaap	Direct Premiums Earned DirectPremiumsEarned	3416687000	USD
CY2020	us-gaap	Ceded Premiums Earned CededPremiumsEarned	56212000	USD
CY2019	us-gaap	Ceded Premiums Earned CededPremiumsEarned	56725000	USD
CY2018	us-gaap	Ceded Premiums Earned CededPremiumsEarned	48941000	USD
CY2020	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	8067000	USD
CY2019	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	910000	USD
CY2018	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	665000	USD
CY2020	us-gaap	Premiums Earned Net PremiumsEarnedNet	3555635000	USD
CY2019	us-gaap	Premiums Earned Net PremiumsEarnedNet	3599418000	USD
CY2018	us-gaap	Premiums Earned Net PremiumsEarnedNet	3368411000	USD

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$MCY
MERCURY GENERAL CORP Stock $mcy

2020 Q4 Form 10-K Financial Statement

#000006499621000004 Filed on February 16, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MCY MERCURY GENERAL CORP Stock $mcy

2020 Q4 Form 10-K Financial Statement

#000006499621000004 Filed on February 16, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MCY
MERCURY GENERAL CORP Stock $mcy