Geographic Concentration Risk Geographic Concentration Risk [Member] Due in one year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Reinsurance recoverable and receivable Increase (Decrease) in Reinsurance Recoverable Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Schedule of Cash and Cash Equivalents Schedule of Cash and Cash Equivalents [Table Text Block] Term Loan Long-Term Debt, Gross Schedule of Unrealized Losses Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Real estate exit costs Real Estate Exit Costs [Member] Real Estate Exit Costs Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Schedule of Reconciliation of Reserve Balances for Loss and LAE, Net of Reinsurance Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Net realized gains on investments Gain (Loss) on Investments Debt Instrument [Axis] Debt Instrument [Axis] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] INVESTMENTS Investment [Text Block] Additional paid-in capital Additional Paid in Capital Gross loss and LAE reserves, January 1 Gross loss and LAE reserves, September 30 Liability for Claims and Claims Adjustment Expense Due five years through 10 years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Fair Value Measurement [Domain] Fair Value Measurement [Domain] Financial Instruments [Domain] Financial Instruments [Domain] Variable rate percentage (in percent) Debt Instrument, Basis Spread on Variable Rate Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items] Statistical Measurement [Domain] Statistical Measurement [Domain] Proceeds from issuance of debt and related warrants Proceeds from Issuance of Debt Common stock—option exercises and restricted stock units vesting, net of shares withheld for employee taxes (in shares) Exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Stated percentage (in percent) Debt Instrument, Interest Rate, Stated Percentage Share-Based Payment Arrangement [Abstract] Conversion of Class B to Class A Stock Issued During Period, Value, Conversion of Convertible Securities Beginning balance (in shares) Ending balance (in shares) Temporary Equity, Shares Outstanding Long Term Warrant Long Term Warrant [Member] Long Term Warrant Net loss Net loss Net loss Net Income (Loss) Attributable to Parent Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Series A Convertible Preferred Stock Series A Convertible Preferred Stock [Member] Series A Convertible Preferred Stock Anti-dilutive securities (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Due after one year through five years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Subsequent Event Type [Axis] Subsequent Event Type [Axis] Tranche 4 Share Based Compensation Award Tranche Four [Member] Share Based Compensation Award Tranche Four Debt instrument, floor interest rate (in percent) Debt Instrument, Floor Interest Rate Debt Instrument, Floor Interest Rate Net investment income Net investment income Net Investment Income Equity Component [Domain] Equity Component [Domain] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Other insurance expense (benefit) Other Insurance Expense (Benefit) [Member] Other Insurance Expense (Benefit) Scenario [Axis] Scenario [Axis] Secured debt Secured Debt [Member] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Total assets at fair value Assets, Fair Value Disclosure Restructuring Plan [Axis] Restructuring Plan [Axis] Investment, Name [Domain] Investment, Name [Domain] Warrant compensation expense APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Warrants APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Warrants Plan Name [Axis] Plan Name [Axis] Fair Value Total AFS securities Debt Securities, Available-for-Sale Unrecognized compensation cost Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Plan Name [Domain] Plan Name [Domain] Premiums earned: Premiums Earned, Net [Abstract] Statement of Cash Flows [Abstract] Entity Address, State or Province Entity Address, State or Province Level 1 Fair Value, Inputs, Level 1 [Member] Prepaid reinsurance premiums Prepaid Reinsurance Premiums Outstanding, weighted-average remaining contractual term (in years) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Warrant compensation expense Adjustment of Warrants Granted for Services Award Type [Axis] Award Type [Axis] Warrants issued and outstanding shares percentage (in percent) Class Of Warrants Issued And Outstanding Shares Percentage Class Of Warrants Issued And Outstanding Shares Percentage Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Total restructuring costs Restructuring Costs Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Schedule of AFS Debt Securities Debt Securities, Available-for-Sale [Table Text Block] Entity Listings [Line Items] Entity Listings [Line Items] Other liabilities Other Liabilities Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Trading days weighted average price Warrants Issued Exercise Price, Trading Days Weighted Average Price Warrants Issued Exercise Price, Trading Days Weighted Average Price Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Total liabilities Liabilities Unearned premiums Increase (Decrease) in Unearned Premiums Geographical [Axis] Geographical [Axis] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Prior years Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years Direct Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Gross Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Gross Increase (Decrease) in Temporary Equity [Roll Forward] Increase (Decrease) in Temporary Equity [Roll Forward] Vested Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Amortized cost, short term investments Debt Securities, Available-for-Sale, Amortized Cost, Current Conversion of stock, shares converted Conversion of Stock, Shares Converted Short-term investments (amortized cost: $0.4 and zero at September 30, 2022 and December 31, 2021, respectively) Debt Securities, Available-for-Sale, Current Workforce reduction Restructuring and Related Cost, Number of Positions Eliminated Change in net unrealized gains (losses) on investments: AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Document Type Document Type Weighted-Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] SOFR Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] Net realized gains on investments Debt Securities, Available-for-Sale, Realized Gain (Loss) Number of Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Forfeited, expired or canceled (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period Assets Assets, Fair Value Disclosure [Abstract] Restructuring Type [Axis] Restructuring Type [Axis] Beginning balance, weighted-average grant date fair value (in dollars per share) Ending balance, weighted-average grant date fair value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value LONG-TERM DEBT Debt Disclosure [Text Block] Entity Shell Company Entity Shell Company Class B Shares Common Class B [Member] Investments: Investments [Abstract] Direct Direct Premiums Earned Schedule of Net Investment Income Investment Income [Table Text Block] Debt Instrument, Covenant Compliance [Domain] Debt Instrument, Covenant Compliance [Domain] Debt Instrument, Covenant Compliance [Domain] Net Investment Income [Line Items] Net Investment Income [Line Items] Financial Instrument [Axis] Financial Instrument [Axis] Other investments Other Investments Subsequent event Subsequent Event [Member] Document Period End Date Document Period End Date Tranche 1 Share-Based Payment Arrangement, Tranche One [Member] Warrants issuance costs Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Schedule of Carrying Amounts and Fair Values of Financial Instruments Fair Value, Liabilities Measured on Recurring and Nonrecurring Basis [Table Text Block] AA+, AA, AA-, A-1 Standard & Poor's, AA Plus, AA, AA Minus, A Minus One Rating [Member] Standard & Poor's, AA Plus, AA, AA Minus, A Minus One Rating Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-Sale [Table] Schedule of AOCI Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Total assets Assets Total paid Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid Debt Disclosure [Abstract] Earnings Per Share [Abstract] Income Statement Location [Axis] Income Statement Location [Axis] Tranche 3 Share-Based Payment Arrangement, Tranche Three [Member] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Schedule of Credit Ratings Fair Value, Concentration of Risk [Table Text Block] Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Exercised, weighted-average exercise price (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Purchases of indefinite-lived intangible assets and transaction costs Payments For Asset Acquisitions Payments For Asset Acquisitions Long-term debt Long-Term Debt, Fair Value Accounting Policies [Abstract] Accounting Policies [Abstract] Net realized losses (gains) on investments reclassified from AOCI to net loss Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent Total Premiums Written, Gross Redeemable convertible preferred stock, $0.0001 par value, 100.0 shares authorized, 14.1 shares issued and outstanding at September 30, 2022 and December 31, 2021 (liquidation preference of $126.5) Beginning balance Ending balance Temporary Equity, Carrying Amount, Attributable to Parent Loss before income tax expense Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] LOSS PER SHARE Earnings Per Share [Text Block] Due after one year through five years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Reinsurance recoverable on unpaid losses Plus reinsurance recoverable on unpaid losses Reinsurance Recoverable for Unpaid Claims and Claims Adjustments Municipal securities Municipal Bonds [Member] Short-term investments Short-Term Investments [Member] Award Type [Domain] Award Type [Domain] Residential mortgage-backed securities Residential Mortgage-Backed Securities [Member] Shares issued (in shares) Class of Warrant or Right, Number of Securities Called by Warrants or Rights Unrecognized compensation cost, period of recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Total, unrealized loss Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Restructuring Plan [Domain] Restructuring Plan [Domain] Schedule of Fair Value Fair Value, by Balance Sheet Grouping [Table Text Block] Entity Registrant Name Entity Registrant Name SUBSEQUENT EVENTS Subsequent Events [Text Block] Insurance [Abstract] Accounts payable and accrued expenses Accounts Payable and Accrued Liabilities Reclassification of early-exercised stock options from liabilities APIC, Share-Based Payment Arrangement, Recognition and Exercise Covenant Scenario 1 Covenant Scenario 1 [Member] Covenant Scenario 1 Entity Address, City or Town Entity Address, City or Town Assumed Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Assumed Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Assumed Gross Written Premiums Gross Written Premiums [Member] Gross Written Premiums Operating expenses: Operating Expenses [Abstract] Basis of Consolidation Consolidation, Policy [Policy Text Block] Minimum Minimum [Member] Due in one year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Statement of Financial Position [Abstract] Entity Emerging Growth Company Entity Emerging Growth Company Debt Instrument, Covenant Compliance [Axis] Debt Instrument, Covenant Compliance [Axis] Debt Instrument, Covenant Compliance Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Commitments and Contingencies Disclosure [Abstract] Investment, Name [Axis] Investment, Name [Axis] FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] Trading Symbol Trading Symbol Entity File Number Entity File Number Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Investment Income [Table] Investment Income [Table] Entity Listings [Table] Entity Listings [Table] External Credit Rating, Standard & Poor's [Domain] External Credit Rating, Standard & Poor's [Domain] Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Restricted stock unit expense Restricted stock unit expense Restricted stock units Restricted Stock Units (RSUs) [Member] Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Use of Estimates Use of Estimates, Policy [Policy Text Block] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Other comprehensive loss: Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Assumed Assumed Premiums Earned Concentration percentage (in percent) Concentration Risk, Percentage Subsequent Events [Abstract] Total revenues Revenues Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value [Table] Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table] Root Reinsurance Company, Ltd. Root Reinsurance Company, Ltd. [Member] Root Reinsurance Company, Ltd. Accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities INCOME TAXES Income Tax Disclosure [Text Block] 2020 Equity Incentive Plan 2020 Equity Incentive Plan [Member] 2020 Equity Incentive Plan 12 months or more, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Exercise price (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Loss per common share: basic (both Class A and B) (in dollars per share) Earnings Per Share, Basic Covenant Scenario 2 Covenant Scenario 2 [Member] Covenant Scenario 2 Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] LOSS AND LOSS ADJUSTMENT EXPENSE RESERVES Insurance Disclosure [Text Block] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Counterparty Name [Domain] Counterparty Name [Domain] Treasury Stock Treasury Stock [Member] Sales and marketing Selling and Marketing Expense Total stockholders’ equity Beginning balance Ending balance Stockholders' Equity Attributable to Parent Forfeited, expired or canceled, weighted-average grant date fair value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Due five years through 10 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Vesting [Domain] Vesting [Domain] Allowance for Expected Credit Losses Debt Securities, Available-for-Sale, Allowance for Credit Loss Entity Interactive Data Current Entity Interactive Data Current Commercial mortgage backed securities Commercial Mortgage-Backed Securities [Member] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Ceded Ceded Premiums Earned Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Sales of investments Proceeds from Sale of Debt Securities, Available-for-Sale Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Accumulated Loss Retained Earnings [Member] Georgia GEORGIA Unrecognized compensation cost, options Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Class A and Class B Common Stock(1) Common Stock [Member] Schedule of Share-Based Compensation Expense Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Other comprehensive loss Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Other comprehensive loss before reclassifications OCI, before Reclassifications, Net of Tax, Attributable to Parent Premiums receivable, net of allowance of $3.3 and $5.4 at September 30, 2022 and December 31, 2021, respectively Premiums Receivable, Net Shares available for issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant Class of Stock [Axis] Class of Stock [Axis] Summary of RSU Activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Statement [Table] Statement [Table] Bad debt expense Premium Receivable, Credit Loss Expense (Reversal) Vested, weighted-average grant date fair value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Document Quarterly Report Document Quarterly Report Term Loan Term Loan C [Member] Term Loan C Technology and development Technology And Development Expense [Member] Technology And Development Expense Statistical Measurement [Axis] Statistical Measurement [Axis] All others states All Other States [Member] All Other States Accumulated loss Retained Earnings (Accumulated Deficit) Due after 10 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 U.S. Treasury securities and agencies US Treasury and Government [Member] Equity Components [Axis] Equity Components [Axis] Scenario [Domain] Scenario [Domain] AAA Standard & Poor's, AAA Rating [Member] Colorado COLORADO Less than 12 months, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Document Fiscal Year Focus Document Fiscal Year Focus Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Statement [Line Items] Statement [Line Items] Beginning balance (in shares) Ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Losses and loss adjustment expenses reserves Increase (Decrease) in Liability for Claims and Claims Adjustment Expense Reserve Variable Rate [Domain] Variable Rate [Domain] Effects of Reinsurance [Line Items] Effects of Reinsurance [Line Items] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Assumed Assumed Premiums Written Premiums written: Premiums Written, Net [Abstract] Gross Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] OTHER COMPREHENSIVE LOSS AND ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME Comprehensive Income (Loss) Note [Text Block] Organizational Realignment Organizational Realignment [Member] Organizational Realignment Type of Restructuring [Domain] Type of Restructuring [Domain] Document Transition Report Document Transition Report Local Phone Number Local Phone Number Loss and loss adjustment expenses Liability For Claims And Claims Adjustment Expense [Member] Liability For Claims And Claims Adjustment Expense Summary of Option Activity Share-Based Payment Arrangement, Option, Activity [Table Text Block] Operating loss Operating Income (Loss) Common stock, shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Credit rating Credit Rating Concentration Risk [Member] Credit Rating Concentration Risk Treasury stock, beginning balance (in shares) Treasury stock, ending balance (in shares) Treasury Stock, Shares Adjustments to reconcile net loss to net cash used in operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Income tax expense Income Tax Expense (Benefit) Geographical [Domain] Geographical [Domain] Beginning balance Ending balance Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Nonvested Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Income Statement [Abstract] Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Additional Paid-in Capital Additional Paid-in Capital [Member] Number of tranches Class Of Warrant Or Right, Number Of Tranches Class Of Warrant Or Right, Number Of Tranches Document Fiscal Period Focus Document Fiscal Period Focus Ceded Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Ceded Liability For Unpaid Claims And Claims Adjustment Expense, Incurred Claims, Ceded Exercised, aggregate intrinsic value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value Weighted-average common shares outstanding: diluted (both Class A and B) (in shares) Weighted Average Number of Shares Outstanding, Diluted Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Total investments Investments Common stock, value Common Stock, Value, Issued Carrying amount Reported Value Measurement [Member] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Granted, weighted-average grant date fair value (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Schedule of Anti-Dilutive Securities Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Net realized gains on investments Realized Investment Gains (Losses) Debt instrument, issued shares insurance policies (in shares) Debt Instrument, Covenant Compliance, Insurance Policies Issued Debt Instrument, Covenant Compliance, Insurance Policies Issued Fee and other income Other Income Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Cash, cash equivalents and restricted cash at beginning of period Cash, cash equivalents and restricted cash at end of period Total cash, cash equivalents and restricted cash shown in the condensed consolidated statements of cash flows Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Insurance subsidiaries amount Debt Instrument, Covenant Compliance, Minimum Cash And Cash Equivalents Debt Instrument, Covenant Compliance, Minimum Cash And Cash Equivalents AFS securities Debt Securities, Available For Sale [Member] Debt Securities, Available For Sale Schedule of Comprehensive Loss For Reinsurance Schedule of Direct and Assumed Written Premiums Effects of Reinsurance [Table Text Block] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Term Loan warrants issued Adjustments to Additional Paid in Capital, Warrant Issued Proceeds from exercise of stock options and restricted stock units, net of tax proceeds/(withholding) Proceeds from Stock Options Exercised Common stock, shares issued (in shares) Common Stock, Shares, Issued Income Statement Location [Domain] Income Statement Location [Domain] Total, fair value Debt Securities, Available-for-Sale, Unrealized Loss Position Amendment Flag Amendment Flag Net cash (used in) provided by investing activities Net Cash Provided by (Used in) Investing Activities Debt amount Debt Instrument, Face Amount Investment Type [Axis] Investment Type [Axis] Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Other insurance expense (benefit) Other Insurance Expense (Income) Other Insurance Expense (Income) Gross Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Entity Current Reporting Status Entity Current Reporting Status Cash expenditures Payments for Restructuring Net paid loss and LAE related to: Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid [Abstract] Severance, benefits, and related costs Employee Severance [Member] Federal income tax rate (in percent) Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Tranche 5 Share Based Compensation Award Tranche Five [Member] Share Based Compensation Award Tranche Five Counterparty Name [Axis] Counterparty Name [Axis] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Outstanding, beginning balance (in shares) Outstanding, ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Unamortized discount, debt issuance costs and warrants Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Liabilities: Liabilities [Abstract] Depreciation and amortization Depreciation, Amortization and Accretion, Net Repayments of long-term debt Repayments of Long-Term Debt Sales and marketing Selling and Marketing Expense [Member] Stock option expense Options to purchase common stock Share-Based Payment Arrangement, Option [Member] Indiana MISSOURI Common stock—option exercises and restricted stock units vesting, net of shares withheld for employee taxes Stock Issued During Period, Value, Stock Options Exercised Forfeited, expired or canceled (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Long-term debt and warrants Total Long-Term Debt RESTRUCTURING COSTS Restructuring and Related Activities Disclosure [Text Block] Common stock, shares authorized (in shares) Common Stock, Shares Authorized Carvana Carvana [Member] Carvana Other investments Other investments Other Investment Companies [Member] Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Total operating expenses Operating Expenses Maximum Maximum [Member] Accumulated other comprehensive (loss) income Accumulated Other Comprehensive Income (Loss), Net of Tax Effects of Reinsurance [Table] Effects of Reinsurance [Table] Class A Shares Common Class A [Member] Nevada NEVADA Cash and cash equivalents Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Change in fair value of equity securities Equity Securities, FV-NI, Gain (Loss) Software costs Software Costs [Member] Software Costs Entity Small Business Entity Small Business Measurement Basis [Axis] Measurement Basis [Axis] Schedule of Stockholders' Equity Note, Warrants or Rights Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] Revenues: Revenues [Abstract] Restricted cash Restricted cash Restricted Cash Purchases of investments Payments to Acquire Debt Securities, Available-for-Sale BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Significant Accounting Policies [Text Block] Net premiums earned Net premiums earned Premiums Earned, Net Louisiana LOUISIANA Number of Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Root Insurance Company Root Insurance Company [Member] Root Insurance Company Payment-in-kind interest expense Paid-in-Kind Interest Outstanding, aggregate intrinsic value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Title of 12(b) Security Title of 12(b) Security Interest on bonds Bonds [Member] Conversion of stock, shares issued Conversion of Stock, Shares Issued Subsequent Event [Line Items] Subsequent Event [Line Items] Debt Instrument [Line Items] Debt Instrument [Line Items] Accrued interest payable Interest Payable Less than 12 months, unrealized loss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Class of Stock [Line Items] Class of Stock [Line Items] Reinsurance recoverable and receivable, net of allowance of $0.1 and $0.2 at September 30, 2022 and December 31, 2021, respectively Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments Investments, Debt and Equity Securities [Abstract] Technology and development Technology And Development Expense Technology And Development Expense 12 months or more, unrealized loss Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Liabilities, Redeemable Convertible Preferred Stock and Stockholders’ Equity Liabilities and Equity [Abstract] Estimated Fair Value Estimate of Fair Value Measurement [Member] Granted, weighted-average exercise price (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Amortized Cost Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Forfeited, expired and canceled, weighted-average exercise price (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Current year Current Year Claims and Claims Adjustment Expense Severance, benefits, and related costs Restructuring Charges Other assets Increase (Decrease) in Other Operating Assets Credit Rating, Standard & Poor's [Axis] Credit Rating, Standard & Poor's [Axis] NATURE OF BUSINESS Nature of Operations [Text Block] Warrant Warrants to purchase common stock Warrant [Member] Entity Filer Category Entity Filer Category Weighted-average common shares outstanding: basic (both Class A and B) (in shares) Weighted Average Number of Shares Outstanding, Basic Reinsurance premiums payable Reinsurance Payable Debt instrument, covenant compliance, maximum monthly cash spend Debt Instrument, Covenant Compliance, Maximum Monthly Cash Spend Debt Instrument, Covenant Compliance, Maximum Monthly Cash Spend Prior years Incurred losses and LAE attributable to prior accident years Prior Year Claims and Claims Adjustment Expense Ownership percentage (as percent) Equity Method Investment, Ownership Percentage Total share-based compensation expense Share-Based Payment Arrangement, Expense Commitments and Contingencies (Note 11) Commitments and Contingencies Security Exchange Name Security Exchange Name Outstanding, beginning balance, weighted-average exercise price (in dollars per share) Outstanding, ending balance, weighted-average exercise price (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Gain on lease modification Gain (Loss) On Lease Modification Gain (Loss) On Lease Modification Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] General and administrative General and Administrative Expense General and Administrative Expense [Member] South Carolina SOUTH CAROLINA Conversion of Class B to Class A (in shares) Stock Issued During Period, Shares, Conversion of Convertible Securities Prepaid reinsurance premiums Increase (Decrease) in Prepaid Reinsurance Premiums Root Property & Casualty Insurance Company Root Property & Casualty Insurance Company [Member] Root Property & Casualty Insurance Company Interest on deposits and cash equivalents Cash and Cash Equivalents [Member] Cover [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Level 3 Fair Value, Inputs, Level 3 [Member] Fixed maturities available-for-sale, at fair value (amortized cost: $126.6 and $129.5 at September 30, 2022 and December 31, 2021, respectively) Debt Securities, Available-for-Sale, Noncurrent SHARE-BASED COMPENSATION Share-Based Payment Arrangement [Text Block] Restructuring and Related Activities [Abstract] Total fixed maturities Fixed Maturities [Member] Other assets Other Assets Net premiums written Premiums Written, Net Net incurred loss and LAE related to: Losses and LAE incurred: Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims [Abstract] Investments [Domain] Investments [Domain] Allowance for premiums receivable Premium Receivable, Allowance for Credit Loss Forecast Forecast [Member] Total liabilities, redeemable convertible preferred stock and stockholders’ equity Liabilities and Equity Debt instrument, term Debt Instrument, Term Current year Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year Pennsylvania PENNSYLVANIA Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] A+, A, A- Standard & Poor's, A Plus, A, A Minus Rating [Member] Standard & Poor's, A Plus, A, A Minus Rating Fair value of warrants percentage (in percent) Fair Value Of Warrants Percentage Fair Value Of Warrants Percentage Organization, Consolidation and Presentation of Financial Statements [Abstract] AOCI Attributable to Parent, Net of Tax [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Level 2 Fair Value, Inputs, Level 2 [Member] Current Fiscal Year End Date Current Fiscal Year End Date Oklahoma OKLAHOMA Amortized Cost Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost [Abstract] Realized gains on investments Debt Securities, Available-for-Sale, Realized Gain Vesting [Axis] Vesting [Axis] Loss per common share: diluted (both Class A and B) (in dollars per share) Earnings Per Share, Diluted Tranche 2 Share-Based Payment Arrangement, Tranche Two [Member] Conversion ratio Stockholders' Equity Note, Stock Split, Conversion Ratio Amortized cost, fixed maturities Debt Securities, Available-for-Sale, Amortized Cost, Noncurrent Payment of preferred stock and related warrants issuance costs Payments of Stock Issuance Costs Common stock—share-based compensation expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Concentration Risk Type [Axis] Concentration Risk Type [Axis] Due after 10 years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Net loss and LAE reserves, January 1 Net loss and LAE reserves, September 30 Liability for Unpaid Claims and Claims Adjustment Expense, Net Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Capitalization of internally developed software Payments to Develop Software Corporate debt securities Corporate Debt Securities [Member] Investment expense Investment Income, Investment Expense BBB+, BBB, BBB- Standard & Poor's, BBB Plus, BBB, BBB Minus Rating [Member] Standard & Poor's, BBB Plus, BBB, BBB Minus Rating Entity Address, Address Line Two Entity Address, Address Line Two Entity Address, Address Line One Entity Address, Address Line One REINSURANCE GEOGRAPHICAL BREAKDOWN OF GROSS WRITTEN PREMIUM Reinsurance [Text Block] Class of Stock [Domain] Class of Stock [Domain] Ceded Ceded Premiums Written Fair Value Disclosures [Abstract] Interest expense Interest Expense Loss and loss adjustment expenses Total incurred Total incurred Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims Changes in net unrealized losses on investments OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, after Tax Short-term investments Debt Securities Available For Sale Current [Member] Debt Securities Available For Sale Current Realized gain value Gross Investment Income, Operating Utah UTAH Schedule of Long Term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Equity [Abstract] Subsequent Event [Table] Subsequent Event [Table] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Entity Tax Identification Number Entity Tax Identification Number Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract] Premiums receivable Increase (Decrease) in Premiums Receivable Reinsurance premiums payable Increase (Decrease) in Reinsurance Payables Net increase (decrease) in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Fair value of warrants Warrants Not Settleable in Cash, Fair Value Disclosure Restructuring Costs Restructuring and Related Costs [Table Text Block] Entity Central Index Key Entity Central Index Key Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Weighted-Average Grant Date Fair Value per Share Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Short Term Warrant Short Term Warrant [Member] Short Term Warrant Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Allowance for credit loss Reinsurance Recoverable, Allowance for Credit Loss City Area Code City Area Code General and administrative General and Administrative Expense Assets Assets [Abstract] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Other debt obligations Other Debt Obligations [Member] Statement of Stockholders' Equity [Abstract] Redeemable convertible preferred stock (as converted to common stock) Nonvested Shares Subject To Repurchase [Member] Nonvested Shares Subject To Repurchase Direct Direct Premiums Written Proceeds from maturities, call and pay downs of investments Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-Sale Fair Value Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value [Abstract] Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Share-based compensation Share-Based Payment Arrangement, Noncash Expense Preferred stock, liquidation preference Preferred Stock, Liquidation Preference, Value Variable Rate [Axis] Variable Rate [Axis] Warrants outstanding (in shares) Class of Warrant or Right, Outstanding Other liabilities Increase (Decrease) in Other Operating Liabilities Purchases of fixed assets Payments to Acquire Property, Plant, and Equipment Schedule of Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Texas TEXAS Realized losses on investments Debt Securities, Available-for-Sale, Realized Loss Unearned premiums Unearned Premiums Loss and loss adjustment expense reserves Liability For Claims And Claims Adjustment Expense, Gross Liability For Claims And Claims Adjustment Expense, Gross Workforce reduction, percent Restructuring and Related Cost, Number of Positions Eliminated, Period Percent Nonvested shares subject to repurchase Redeemable Convertible Preferred Stock [Member]