Insider Trading Arrangements [Line Items] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Accrued investment income Accrued Investment Income Receivable Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Additional paid-in capital Additional Paid in Capital Consolidated Balance Sheets [Abstract] Basic (in dollars per share) Basic net income per share (in dollars per share) Net purchases of property and equipment Payments for (Proceeds from) Productive Assets Cash paid during period - Interest Interest Paid, Excluding Capitalized Interest, Operating Activities Ceded Credit Risk, Reinsurer [Domain] Ceded Credit Risk, Reinsurer [Axis] Ceded Credit Risk [Line Items] Ceded Credit Risk [Table] Current income taxes Increase (Decrease) in Income Taxes Payable Reinsurance balances payable Increase (Decrease) in Reinsurance Payables Net sales of short-term investments Payments for (Proceeds from) Short-Term Investments Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accrued expenses Increase (Decrease) in Accrued Liabilities Due from affiliate Increase (Decrease) Due from Affiliates Losses and loss expenses Balance at end of period Balance at January 1 Liability for Claims and Claims Adjustment Expense Class B Common Stock [Member] Common Class B [Member] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Common stock Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Attributable to Parent Percentage of accumulation of losses Contracts in Force Subject to Participation through Reinsurance, Ratio Corporate Securities [Member] Corporate Debt Securities [Member] Interest rate Debt instrument due date Deferred policy acquisition costs Deferred Policy Acquisition Cost Amortization of deferred policy acquisition costs Deferred Policy Acquisition Costs, Amortization Expense Deferred acquisition costs Increase (Decrease) in Deferred Policy Acquisition Costs Depreciation, amortization and other non-cash items Depreciation, Depletion and Amortization, Nonproduction Diluted (in dollars per share) Diluted net income per share (in dollars per share) Compensation expense in stock compensation plans Share-Based Payment Arrangement, Expense Income tax benefit of stock compensation plans Share-Based Payment Arrangement, Expense, Tax Benefit Equity Securities [Member] Equity Securities [Member] Net losses and loss expenses Policyholder dividends Policyholder Dividends, Expense Other underwriting expenses Other Underwriting Expense Fixed interest rate on advance Federal Home Loan Bank, Advance, Branch of FHLBank, Interest Rate FHLB stock purchased and owned Federal Home Loan Bank Stock Reinsurance Transactions [Abstract] Consolidated Statements of Income [Abstract] After tax decrease in retained earnings Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle Income Taxes Income Tax Disclosure [Text Block] Federal income taxes recoverable Income Taxes Receivable Net cash paid during period - Taxes Income Taxes Paid, Net Accrued investment income Increase (Decrease) in Accrued Investment Income Receivable Incurred related to [Abstract] Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract] Liability for Claims and Claims Adjustment Expense [Abstract] Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract] Other intangible assets Intangible Assets, Net (Excluding Goodwill) Goodwill Goodwill Interest Interest Expense, Operating and Nonoperating Total investments Investments Investments Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Total liabilities Liabilities Liabilities Liabilities [Abstract] Total liabilities and stockholders' equity Liabilities and Equity Liabilities and Stockholders' Equity Liabilities and Equity [Abstract] Borrowing capacity currently available Line of Credit Facility, Current Borrowing Capacity Line of Credit Facility, Lender [Domain] Unsecured demand line of credit Line of credit facility remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Line of Credit Facility [Abstract] Line of Credit Facility [Abstract] Lender Name [Axis] Line of Credit Facility [Line Items] Line of Credit Facility [Table] Lines of Credit [Member] Line of Credit [Member] Borrowings under lines of credit Long-Term Line of Credit Outstanding borrowings Long-Term Debt Total paid Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Held to maturity, at amortized cost (net of allowance for expected credit losses of $1,353,571 and $1,325,847) Balance at beginning of period Balance at end of period Held to maturity, carrying value Mortgage-Backed Securities [Member] Collateralized Mortgage-Backed Securities [Member] Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Cash Flows from Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Investing Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Net income Net income Allocation of net income Net Income (Loss) Available to Common Stockholders, Basic Investment income, net of investment expenses Net investment income Net Investment Income Impact of New Accounting Standard [Abstract] Installment payment fees Insurance Commissions and Fees Valuation allowance related to the portion of operating loss carryforwards Operating Loss Carryforwards, Valuation Allowance Total revenues Revenues Revenues: Revenues: [Abstract] Revenues [Abstract] Other, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Unrealized loss on securities: Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax [Abstract] Unrealized holding loss during the period, net of income tax benefit of $82,974 and $1,964,085 Income tax benefit on unrealized holding (loss) income arising during the period Other Other Liabilities Other Other Nonoperating Income (Expense) Due from affiliate Paid related to [Abstract] Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Cash dividends paid Payments of Dividends Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Premiums earned [Abstract] Premiums Earned, Net, by Business [Abstract] Premiums receivable Premiums Receivable, Net Premiums receivable Increase (Decrease) in Premiums Receivable Prepaid reinsurance premiums Prepaid Reinsurance Premiums Prepaid reinsurance premiums Increase (Decrease) in Prepaid Reinsurance Premiums Issuance of common stock Proceeds from Issuance of Common Stock Available for sale Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Held to maturity Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities Cash from option exercises Proceeds from Stock Options Exercised Property and equipment, net Property, Plant and Equipment, Net Purchases of fixed maturities, held to maturity Payments to Acquire Held-to-Maturity Securities Reinsurance [Abstract] Reinsurance receivable Increase (Decrease) in Reinsurance Recoverable Net balance at January 1 Net balance at end of period Liability for Unpaid Claims and Claims Adjustment Expense, Net Cumulative effect of adoption of updated accounting guidance for credit losses at January 1 Retained earnings Retained Earnings (Accumulated Deficit) Net premiums earned Premiums earned Premiums Earned, Net Summary of Insurance Subsidiaries' Liabilities for Losses and Loss Expenses Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Current year Current Year Claims and Claims Adjustment Expense Prior years Prior Year Claims and Claims Adjustment Expense Segment Information Segment Reporting Disclosure [Text Block] Financial Data by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Segment Reporting Information [Line Items] Schedule of Segment Reporting Information, by Segment [Table] Unrecognized compensation expense related to nonvested share-based compensation granted under the plan Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Consolidated Statements of Cash Flows [Abstract] Consolidated Statements of Comprehensive Income (Loss) [Abstract] Consolidated Statement of Stockholders' Equity [Abstract] Stockholders' Equity Equity, Attributable to Parent [Abstract] Underwriting loss [Abstract] Revenues, Excluding Interest and Dividends [Abstract] Obligations of States and Political Subdivisions [Member] US States and Political Subdivisions Debt Securities [Member] U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member] US Treasury and Government [Member] GAAP underwriting loss Underwriting Income (Loss) Number of shares used in diluted computation (in shares) Weighted Average Number of Shares Outstanding, Diluted Director and employee stock options (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment Weighted-average shares outstanding (in shares) Number of shares used in basic computation (in shares) Weighted Average Number of Shares Outstanding, Basic Common Stock [Member] Cash Cash Corporate Securities [Member] Debt Security, Corporate, US [Member] Due in one year or less, amortized cost Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Due after one year through five years, amortized cost Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Due after five years through ten years, amortized cost Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Due after ten years, amortized cost Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Mortgage-backed securities, amortized cost Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Amortized Cost Due in one year or less, estimated fair value Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Due after one year through five years, estimated fair value Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Due after five years through ten years, estimated fair value Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Due after ten years, estimated fair value Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Mortgage-backed securities, estimated fair value Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value Available For Sale [Abstract] Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract] Available For Sale [Abstract] Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Available for sale, at fair value Available for sale, estimated fair value Total available for sale, estimated fair value Debt Securities, Held-to-Maturity [Table] Held To Maturity [Abstract] Debt Securities, Held-to-Maturity, Fair Value, Maturity [Abstract] Held to maturity, estimated fair value Total held to maturity, estimated fair value Debt Securities, Held-to-Maturity, Fair Value Due in one year or less, estimated fair value Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Due after one year through five years, estimated fair value Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Due after five years through ten years, estimated fair value Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Due after ten years, estimated fair value Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Mortgage-backed securities, estimated fair value Debt Securities, Held-to-Maturity, Maturity, without Single Maturity Date, Fair Value Total assets Assets Collateral pledged at carrying value Financing Receivable, before Allowance for Credit Loss Financial Instruments [Domain] Statement [Table] Antidilutive Securities, Name [Domain] Investments in the fair value hierarchy Investments, Fair Value Disclosure Assets Assets [Abstract] Statement [Line Items] Numerator [Abstract] Net Income (Loss) Available to Common Stockholders, Basic [Abstract] Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Line Items] Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) [Member] Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) [Member] Fair Value Measurements Fair Value Disclosures [Text Block] Class of Stock [Domain] Treasury stock, at cost Treasury Stock, Value Fixed Maturities [Member] Fixed Maturities [Member] Purchases of fixed maturities, available for sale Payments to Acquire Debt Securities, Available-for-Sale Available for sale Class A Common Stock [Member] Common Class A [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Deferred income taxes Increase (Decrease) in Deferred Income Taxes Other expenses, net Other Cost and Expense, Operating Net income per share: Basic net income per share [Abstract] Earnings Per Share, Basic [Abstract] Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] Diluted net income per share [Abstract] Earnings Per Share, Diluted [Abstract] Number of options to purchase Class A shares excluded (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Antidilutive Securities [Axis] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Net Income Per Share [Abstract] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Antidilutive Securities Excluded From Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Equity Method Investments [Table] Debt Securities, Available-for-sale [Line Items] Schedule of Held-to-Maturity Securities [Line Items] Schedule of Equity Method Investments [Line Items] Class of Stock [Axis] Unearned premiums Unearned Premiums Reinsurance balances payable Reinsurance Payable Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Income before income tax expense [Abstract] Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest [Abstract] Ending balance Beginning balance Total stockholders' equity Equity, Attributable to Parent Income tax expense Income tax expense (benefit) Unearned premiums Increase (Decrease) in Unearned Premiums Held To Maturity [Abstract] Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity [Abstract] Due in one year or less, amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Year One Due after one year through five years, amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five Due after five years through ten years, amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 5 through 10 Due after ten years, amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year 10 Mortgage-backed securities, amortized cost Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, without Single Maturity Date Preferred stock, $.01 par value, authorized 2,000,000 shares; none issued Preferred Stock, Value, Issued Other Other Income Gain (Loss) on Securities [Line Items] Expenses: Benefits, Losses and Expenses [Abstract] Total expenses Benefits, Losses and Expenses Equity Components [Axis] Additional Paid-In Capital [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Retained Earnings [Member] Accumulated Net Unrealized Investment Losses [Member] AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Accumulated Other Comprehensive Loss [Member] AOCI Attributable to Parent [Member] Equity Component [Domain] Options [Member] Net investment gains Net investment gains Investment gains Borrowings Long-Term Debt [Text Block] Issuance of common stock (stock compensation plans) Stock Issued During Period, Value, New Issues Share-based compensation Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture Issuance of common stock (stock compensation plans) (in shares) Stock Issued During Period, Shares, New Issues Share-based compensation (in shares) Allocation of net income Net Income (Loss) Available to Common Stockholders, Diluted Cash dividends declared Dividends, Common Stock Ending balance (in shares) Beginning balance (in shares) Shares, Issued Weighted-average shares effect of dilutive securities [Abstract] Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Net Income Per Share Denominator [Abstract] Weighted Average Number of Shares Outstanding, Basic [Abstract] Denominator [Abstract] Weighted Average Number of Shares Outstanding, Diluted [Abstract] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items] Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table] Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Net adjustments Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities Reinsurance Reinsurance [Text Block] Organization Nature of Operations [Text Block] Accrued expenses Accrued Liabilities Cash dividends declared to stockholders Dividends Payable Real Estate [Member] Income before income tax expense Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Numerator [Abstract] Net Income (Loss) Attributable to Parent, Diluted [Abstract] Operating Segments [Member] Operating Segments [Member] Financial Data by Segment [Abstract] Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract] Measurement Frequency [Domain] Fair Value Hierarchy and NAV [Domain] Other Other Assets Recurring Basis [Member] Organization [Abstract] Investments [Abstract] Fair Value Hierarchy and NAV [Axis] Measurement Frequency [Axis] Investments in Available-for-Sale Fixed Maturity and Equity Securities Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Income Taxes [Abstract] Fair Value Measurements [Abstract] Borrowings [Abstract] Total available for sale, amortized cost Debt Securities, Available-for-Sale, Amortized Cost Schedule of Gain (Loss) on Securities [Table] Share-Based Compensation Compensation and Employee Benefit Plans [Text Block] Share-Based Compensation [Abstract] Allowance for Expected Credit Losses Grant of stock options APIC, Share-Based Payment Arrangement, Option, Increase for Cost Recognition Basis of Presentation Basis of Accounting [Text Block] Fixed Maturities with Unrealized Losses Unrealized Gain (Loss) on Investments [Table Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Gross Investment Gains and Losses before Applicable Income Taxes Realized Gain (Loss) on Investments [Table Text Block] Impact of New Accounting Standards [Abstract] Segment Information [Abstract] Accounts receivable - securities Accounts Receivable from Securitization Accounting Standards Update [Domain] Reconciliation of Numerators and Denominators Used in Basic and Diluted Per Share Computations Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Investments [Domain] Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Accounting Standards Update [Axis] Organization Financial Instrument [Axis] Impact of New Accounting Standards Federal Home Loan Bank of Stock Purchased, Collateral Pledged and Assets Related [Abstract] Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract] Credit Facility [Axis] Credit Facility [Domain] Weighted average period of unrecognized compensation expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Impact of New Accounting Standards Accounting Standards Update and Change in Accounting Principle [Text Block] Number of operating segments Number of Operating Segments Net unrealized losses arising prior to reclassification date OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment and Tax Other comprehensive income (loss) Other comprehensive loss Fair Value Measurement Inputs and Valuation Techniques [Abstract] Investment Type [Axis] Schedule of Investments [Table] Schedule of Investments [Line Items] Property Insurance [Member] Premiums and losses related to certain products SEC Schedule, 12-17, Insurance Companies, Reinsurance, Premium, Percentage Assumed to Net Reinsurance Receivable [Table] Reinsurance Receivable [Line Items] Personal Lines [Member] Property and Casualty, Personal Insurance [Member] Commercial Lines [Member] Property and Casualty, Commercial Insurance [Member] Reinsurance receivable (net of allowance for expected credit losses of $932,350 and $1,394,074) Balance at beginning of period Balance at end of period Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments Balance at beginning of period Balance at end of period Reinsurance receivable, allowance for expected credit losses Reinsurance Recoverable, Allowance for Credit Loss Reinsurance Receivable, Net of Allowance for Expected Credit Losses [Abstract] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification out of Accumulated Other Comprehensive Income [Member] Reclassification adjustment for (gains) losses included in net income, net of income tax expense (benefit) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Income tax (benefit) expense on reclassification adjustment for losses (gains) Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Available for sale, gross unrealized losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Available for sale, gross unrealized gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Held to maturity, gross unrealized losses Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss Held to maturity, gross unrealized gains Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain Federal Home Loan Bank, Advances, Option [Axis] Federal Home Loan Bank, Advances, Option [Domain] Federal home loan bank, cash advance at fixed rate advances Federal Home Loan Bank, Advances, Fixed Rate Current year Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year Plus reinsurance recoverable Less reinsurance recoverable Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Total incurred Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Prior years Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years Deferred tax asset, net Deferred Income Tax Assets, Net Losses and loss expenses Increase (Decrease) in Liability for Claims and Claims Adjustment Expense Reserve Treasury Stock [Member] Treasury Stock, Common [Member] Net increase (decrease) in cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Cash at end of period Cash at beginning of period Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Lease income Operating Lease, Lease Income Less than 12 months, unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss More than 12 months, unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Debt Securities, Available-for-Sale [Table] Less than 12 months, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months More than 12 months, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Equity securities, at fair value Estimated fair value Equity Securities, FV-NI, Current Cost Equity Securities, FV-NI, Cost Gross gains Gross unrealized gains on equity securities Gross losses Gross unrealized losses on equity securities Equity Securities, FV-NI, Unrealized Loss Workers' Compensation Insurance [Member] Liability Insurance [Member] ASU 2016-13 [Member] Held-to-Maturity Fixed-Maturity Securities Debt Securities, Held-to-Maturity, Allowance for Credit Loss [Table Text Block] Reinsurance Receivable Allowance for Expected Credit Losses [Abstract] Debt Securities, Held-to-Maturity, Allowance for Credit Loss [Roll Forward] Current period change for expected credit losses Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Period Increase (Decrease) Current period change for expected credit losses Reinsurance Recoverable, Allowance for Credit Loss, Period Increase (Decrease) Balance at beginning of period Balance at end of period Held to maturity, allowance for expected credit losses Held to maturity, allowance for credit loss Allowance for Expected Credit Losses [Abstract] Allowance for Expected Credit Losses [Abstract] Reinsurance Recoverable, Allowance 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Measurement [Domain] Minimum [Member] Minimum [Member] Consolidation Items [Axis] Consolidation Items [Domain] FHLB of Pittsburgh [Member] Federal Home Loan Bank of Pittsburgh [Member] Consolidated Entities [Axis] Consolidated Entities [Domain] Product and Service [Domain] Product and Service [Axis] Cumulative Effect, Period of Adoption [Axis] Cumulative Effect, Period of Adoption [Domain] Cumulative Effect, Period of Adoption, Adjustment [Member] Cover [Abstract] Document Type Document Quarterly Report Document Transition Report Entity Interactive Data Current Amendment Flag Document Fiscal Year Focus Document Fiscal Period Focus Document Period End Date Entity Registrant Name Entity Central Index Key Entity File Number Entity Tax Identification Number Entity Incorporation, State or Country Code Current Fiscal Year End Date Entity Current Reporting Status Entity Shell Company Entity Filer Category Entity Small Business Entity Emerging Growth Company Entity Address, Address Line One Entity Address, Address Line Two Entity Address, City or Town Entity Address, State or Province Entity Address, Postal Zip Code City Area Code Local Phone Number Entity Listings [Table] Entity Listings [Line Items] Title of 12(b) Security Trading Symbol Security Exchange Name Entity Common Stock, Shares Outstanding The retention amount of Catastrophe reinsurance agreement contracts. Catastrophe Reinsurance Agreement Contracts Retention Amount Catastrophe reinsurance, set retention amount The amount of workers' compensation and retention amount for workers' compensation losses. Workers' Compensation and Retention Amount Workers' compensation and retention amount Information by reinsurer or group of third party reinsurance. Third Party Reinsurance [Member] Third Party Reinsurance [Member] The retention amount of loss reinsurance agreement contracts. Loss Reinsurance Agreement Contracts Retention Amount Loss reinsurance agreement contracts retention amount The percentage of share in results of pooled business owned by third party. Percentage of Share in Results of Pooled Business Owned by Third Party Percentage of share in results of pooled business owned by third party The maximum amount of loss coverage under reinsurance agreement of property catastrophe. Maximum Amount of Loss Coverage Under Reinsurance Agreement of Property Catastrophe Maximum amount of loss coverage under reinsurance agreement of property catastrophe The amount of statutory accounting practices underwriting income (loss). Statutory Accounting Practices Underwriting Income (Loss) SAP underwriting loss The amount of GAAP adjustments related to underwriting (income) loss. GAAP Adjustments Related to Underwriting (Income) Loss GAAP adjustments Debt Securities, Fair Value and Unrealized Losses by Fixed Maturities [Abstract] The number of securities classified as available for sale in unrealized loss position held by the entity. Number of Securities Classified as Available for Sale in Unrealized Loss Position Number of fixed maturity securities classified as available for sale The amount of amortized cost of bond held at balance sheet date. Amortized Cost of Bond Held Amortized cost of bond held Percentage of threshold limit for investment held at balance sheet date. Threshold Limit for Investment Held Percentage of which the company held security of any issuer The amount of aggregate fair value of bond held at balance sheet date. Aggregate Fair Value of Bond Held Aggregate fair value of bond held A revenue bond issued by a municipality to finance the building or extension of water and sewer systems. Interest and principal payments on the bond are derived from and are limited to revenues received from charges to the users of the systems. Water And Sewer Utility Bonds [Member] Water and Sewer Utility Bonds [Member] Education Bonds are financial products designed specifically for saving and investing to meet lifelong education expenses for yourself, your family or others dear and important to you. Education Bond [Member] Education Bonds [Member] Special revenue bond means any security or other instrument, under which a payment obligation is created, issued by or on behalf of or payable or guaranteed by a governmental unit to finance a project serving a substantial public purpose, and not payable from any of the sources enumerated in subsection (p) of this section; or securities which are the functional equivalent of the foregoing issued by a not-for-profit corporation. Special Revenue Bond [Member] Special Revenue Bonds [Member] Percentage of different kind of bond included in investment in special revenue bonds. Percentage of Different Kind of Bond Included in Investment in Special Revenue Bonds Percentage of investments in special revenue bonds The amount of reclassification adjustment out of accumulated other comprehensive income amortization of unrecognized loss during the reporting period. Reclassification Adjustment out of Accumulated Other Comprehensive Income Amortization of Unrecognized Loss Amortization of other comprehensive loss Tabular disclosure of cost and estimated fair value of equity securities. Schedule of Cost and Estimated Fair Value of Equity Securities [Table Text Block] Cost and Estimated Fair Values of Equity Securities Tabular disclosure of amortized cost and estimated fair value of fixed maturities securities. Schedule of Amortized Cost and Estimated Fair Value of Fixed Maturities Securities [Table Text Block] Amortized Cost and Estimated Fair Values of Fixed Maturities Amount, after allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Deferred Tax Assets, Net, Other Other deferred tax assets, net Operating loss carryforwards [Abstract] Operating Loss Carryforwards [Abstract] Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI); amount less than prior quarter. Equity Securities, FV-NI, Unrealized Loss Amount Less Than Prior Quarter Gross unrealized losses on equity securities Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI); amount less than prior quarter. Equity Securities, FV-NI, Unrealized Gain Amount Less than Prior Quarter Gross unrealized gains on equity securities Amount of gross realized gain/losses on investment. Gross Realized Gain/Loss on Investments Net realized gains (losses) Amount of gross realized loss on investment. Gross Realized Loss on Investments Gross realized losses Amount of credit impairment charges on investments. Credit Impairment Charges on Investments Credit impairment charges Amount of gross realized gain on investment. Gross Realized Gain on Investments Gross realized gains Net Gains and Losses from Investments [Abstract] Amortized Cost and Estimated Fair Values of Fixed Maturities [Abstract] Cost and Estimated Fair Value of Equity Securities [Abstract] Employee service share based compensation tax benefit realized from exercise of stock option. Employee Service Share Based Compensation Tax Benefit Realized from Exercise of Stock Option Tax benefit for tax deductions related to option exercises Basis of Presentation [Abstract] The percentage of voting power owned by major shareholder. Percentage of Voting Power Owned by Major Shareholder Voting power percentage of outstanding common stock The percentage of stock ownership held by major shareholder. Stock Ownership Percentage Held by Major Shareholder Stock ownership percentage held by major shareholder The percentage of share in results of pooled business subsidiary. Percentage of Share in Results of Pooled Business Subsidiary Percentage of share in results of pooled business subsidiary Organizations [Abstract] Organization [Abstract] Name of the entity. Donegal Mutual Insurance Company [Member] Donegal Mutual Insurance Company [Member] Donegal Mutual [Member] Insurance subsidiary, Atlantic States Insurance Company ("Atlantic States"). Atlantic States [Member] Atlantic States [Member] Information by name of manufacturers and traders trust company. Manufacturers And Traders Trust Company [Member] Manufacturers and Traders Trust Company [Member] Pledged assets separately reported assets pledged as collateral at par. Pledged Assets Separately Reported Assets Pledged As Collateral At Par Collateral pledged, at par (carrying value $39,592,120) Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share [Abstract] Antidilutive Securities Excluded from Computation of Earnings (Loss) Per Share [Abstract] The minimum percentage of excess class A common stock dividend over class B dividend for declaration and payment of cash dividends. Minimum Percentage of Excess Class A Common Stock Dividend Over Class B Dividend Minimum percentage of class A common stock declared dividend excess over class B dividend Tabular disclosure of federal home loan bank borrowing capacity. Federal Home Loan Bank of Stock Purchased, Collateral Pledged and Assets Related [Table Text Block] FHLB of Stock Purchased, Collateral Pledged and Assets Related Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments at cost, which approximates fair value. Short-term Investments at Cost Short-term investments, at cost, which approximates fair value Fixed Maturities Investments [Abstract] Fixed maturities Investment [Abstract] Investments Investments [Abstract] Percentage of development related to net carried reserves and resulted primarily from lower-than-expected severity in the workers' compensation and personal automobile lines of business, partially offset by higher-than-expected severity in the commercial automobile and commercial multi-peril lines of business, for accident years. Managements Assertion of Adequacy of Insurance Reserves Percentage Percentage of development The entire disclosure for liability for losses and loss expenses. Liability For Losses And Loss Expenses [Text Block] Liabilities for Losses and Loss Expenses Liabilities for Losses and Loss Expenses [Abstract] Sales of Fixed Maturities [Abstract] Sales of fixed maturities: Maturity of Fixed Maturities [Abstract] Maturity of fixed maturities: