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Weighted average recognition period Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Statement of Financial Position [Abstract] Preferred stock, par value Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Common Stock, Shares, Outstanding Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative And Hedging Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Revolving Secured Line Of Credit [Member] Line of Credit [Member] Warehouse Facility II [Member] Warehouse Facility II [Member] Warehouse Facility II [Member] Warehouse Facility IV [Member] Warehouse Facility IV [Member] Warehouse Facility IV Member Warehouse Facility V [Member] Warehouse Facility V [Member] Warehouse Facility V Member Warehouse Facility VI [Member] Warehouse Facility VI [Member] WarehouseFacilityVI [Member] Warehouse Facility VII [Member] Warehouse Facility VII [Member] Warehouse Facility VII [Member] Warehouse Facility VIII [Member] Warehouse Facility VIII [Member] Warehouse Facility VIII [Member] 2021 Senior Notes [Member] Two Thousand Twenty One Senior Notes [Member] Two Thousand Twenty One Senior Notes [Member] 2023 Senior Notes [Member] Two Thousand Twenty Three Senior Notes [Member] Two Thousand Twenty Three Senior Notes [Member] 2024 Senior Notes [Member] Two Thousand Twenty Four Senior Notes [Member] Two Thousand Twenty Four Senior Notes [Member] 2026 Senior Notes [Member] Two Thousand Twenty Six Senior Notes [Member] Two Thousand Twenty Six Senior Notes [Member] Mortgage [Member] Mortgages [Member] Variable Rate [Axis] Variable Rate 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(Loss) [Member] AOCI Attributable to Parent [Member] Statement [Line Items] Statement [Line Items] Balance, shares Balance Stockholders' Equity Attributable to Parent Net income Net Income (Loss) Attributable to Parent Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Stock-based compensation APIC, Share-based Payment Arrangement, Increase for Cost Recognition Restricted stock awards, net of forfeitures, shares Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Repurchase of common stock, shares Stock Repurchased During Period, Shares Repurchase of common stock Stock Repurchased During Period, Value Balance, shares Balance Description Of Business [Abstract] Description Of Business [Abstract] Description Of Business Nature of Operations [Text Block] Reinsurance [Abstract] Reinsurance [Abstract] Reinsurance Reinsurance [Text Block] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash and cash equivalents Restricted Cash and Cash Equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Debt Debt Disclosure [Text Block] New Accounting Pronouncement Estimated Impact New Accounting Pronouncement Estimated Impact New Accounting Pronouncement Estimated Impact Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Building [Member] Building [Member] Building Improvements [Member] Building Improvements [Member] Data Processing Equipment [Member] Data Processing Equipment [Member] Data Processing Equipment [Member] Software [Member] 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Taxes Stock-based compensation Share-based Payment Arrangement, Noncash Expense Loss on extinguishment of debt Gain (Loss) on Extinguishment of Debt Other Operating Activities, Cash Flow Statement Other Operating Activities, Cash Flow Statement Change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Increase in accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Increase in income taxes receivable Increase (Decrease) in Income Taxes Receivable Increase (decrease) in income taxes payable Increase (Decrease) in Income Taxes Payable Increase in other assets Increase (Decrease) in Other Operating Assets Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash Flows From Investing Activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of restricted securities available for sale Payments to Acquire Available-for-sale Securities Proceeds from sale of restricted securities available for sale Proceeds from Sale and Maturity of Debt Securities, Available-for-sale Maturities of restricted securities available for sale Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Principal collected on Loans receivable Proceeds from Collection of Loans Receivable Advances to Dealers Advances To Dealers The cash outflow for non-recourse payments made to dealers under a portfolio program in exchange for the right to service the underlying consumer loans. Purchases of Consumer Loans Payments to Acquire Loans Receivable Accelerated payments of Dealer Holdback Accelerated Payments of Dealer Holdback The cash outflow for payments made to dealers under our Portfolio Program at the time a pool of 100 or more consumer loans is closed by dealers with a single open pool or at the time 100 consumer loans have been collectively assigned by dealers with multiple open pools. Payments of Dealer Holdback Payments of Dealer Holdback The cash outflow for payments made to dealers under our Portfolio Program from the portion of the collections on the underlying consumer loans that exceed amounts retained by us to recover the advance balance, certain collection costs, and our servicing fee. Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Cash Flows From Financing Activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Borrowings under revolving secured line of credit Proceeds from Long-term Lines of Credit Repayments under revolving secured line of credit Repayments of Long-term Lines of Credit Proceeds from secured financing Proceeds from Issuance of Secured Debt Repayments of secured financing Repayments of Secured Debt Proceeds from issuance of senior notes Proceeds from Issuance of Senior Long-term Debt Repayments of senior notes Repayments of Senior Debt Proceeds from mortgage note Proceeds from Issuance of First Mortgage Bond Payments of debt issuance costs and debt issuance costs Payments of Debt Issuance Costs Repurchase of common stock Payments for Repurchase of Common Stock Other financing activities Proceeds from 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Disclosure [Abstract] Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Restricted cash and cash equivalents Restricted Cash And Cash Equivalents, Fair Value Disclosure Restricted Cash And Cash Equivalents, Fair Value Disclosure Restricted securities available for sale Available-for-sale Securities, Restricted Net investment in Loans receivable Loans Receivable, Fair Value Disclosure Liabilities, Fair Value Disclosure [Abstract] Liabilities, Fair Value Disclosure [Abstract] Revolving secured line of credit Lines of Credit, Fair Value Disclosure Secured financing Secured Financing Fair Value Disclosure Secured Financing Fair Value Disclosure Senior notes Notes Payable, Fair Value Disclosure Other Borrowings Other Borrowings Quarterly Financial Information Disclosure [Abstract] Revenue Revenues Income before provision for income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Net income per share: Basic Earnings Per Share, Basic Net income per share: Diluted Earnings Per Share, Diluted Deferred Tax Assets, Operating Loss Carryforwards Deferred Tax Assets, Operating Loss Carryforwards U.S. federal statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Unrecognized tax benefit that, if recognized, would favorably affect our effective income tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Accrued interest related to uncertain tax positions Unrecognized Tax Benefits, Interest on Income Taxes Accrued Other Income and Other Expense Disclosure [Text Block] Other Income and Other Expense Disclosure [Text Block] Earnings Per Share [Abstract] Schedule Of Weighted Average Shares Outstanding Basic And Diluted Schedule of Weighted Average Number of Shares [Table Text Block] Schedule Of Other Income [Table Text Block] Schedule Of Other Income [Table Text Block] Schedule Of Other Income [Table Text Block] Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table Text Block] Secured Debt [Member] Secured Debt [Member] Term ABS Financing [Member] Term ABS Financing [Member] Term ABS Financing [Member] Senior Notes [Member] Senior Notes [Member] 2020 Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months 2021 Long-term Debt, Maturities, Repayments of Principal in Year Two 2022 Long-term Debt, Maturities, Repayments of Principal in Year Three 2023 Long-term Debt, Maturities, Repayments of Principal in Year Four 2024 Long-term Debt, Maturities, Repayments of Principal in Year Five After 2024 Long-term Debt, Maturities, Repayments of Principal after Year Five Total 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Based Compensation Estimated Allocation Of Recognized Period Costs In Three Years 2023 Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Four Years Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Four Years 2024 Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Five Years Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Five Years Thereafter Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs After Five Years Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs After Five Years Total Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Total Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Total Receivable Type [Axis] Receivable Type [Axis] Receivable [Domain] Receivable [Domain] Dealer Loans [Member] Dealer Loans [Member] Dealer Loans [Member] Purchased Loans [Member] Purchased Loans [Member] Purchased Loans [Member] Loans receivable Loans and Leases Receivable, Net of Deferred Income Allowance for credit losses Loans and Leases Receivable, Allowance Loans receivable, net Loans and Leases Receivable, Net Amount Principal balance outstanding Long-term Line of Credit Principal balance outstanding Senior Notes, Noncurrent Principal balance outstanding Secured Debt Amount available for borrowing Line of Credit Facility, Remaining Borrowing Capacity Loans pledged as collateral Loans Pledged as Collateral Restricted cash and cash equivalents pledged as collateral Interest rate Line of Credit Facility, Interest Rate at Period End Amount available for borrowing Debt Instrument Amount Available For Borrowing Debt Instrument Amount Available For Borrowing Interest rate Debt Instrument, Interest Rate, Effective Percentage Subsequent Event Type [Axis] 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Maximum hedging reserve Maximum Hedging Reserve Maximum hedging reserve Number of warehouse facilities Number Warehouse Facilities Number Warehouse Facilities Percentage of collections on contributed loans Percentage of collections on contributed loans Percentage of collections on contributed loans Monthly servicing fee per financing Monthly Servicing Fee Per Financing Monthly Servicing Fee Per Financing Senior notes stated interest rate Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Repurchase Date Debt Instrument, Repurchase Date Repayments of senior notes Redemption price, percentage of principal amount redeemed Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Debt covenants Debt Instrument Covenant Net Income For Past Two Quarters Debt Instrument Covenant Net Income For Past Two Quarters Investments, Debt and Equity Securities [Abstract] Schedule Of Restricted Securities Available For Sale Schedule of Available-for-sale Securities 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Resulting from Lapse of Applicable Statute of Limitations Unrecognized tax benefits at December 31 Schedule Of Income Tax Provision Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule Of Deferred Tax Assets And Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule Of Reconciliation Of The U.S. Federal Statutory Rate To Effective Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule Of Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Cumulative Incurred Claims [Table] Liability for Claims and Claims Adjustment Expense [Table] Incident Year [Axis] Incident Year [Axis] Incident Year [Axis] Incident Year [Domain] Incident Year [Domain] [Domain] for Incident Year [Axis] Incident Year 2015 [Member] Incident Year 2015 [Member] Incident Year 2015 [Member] Incident Year 2016 [Member] Incident Year 2016 [Member] Incident Year 2016 [Member] Incident Year 2017 [Member] Incident Year 2017 [Member] Incident Year 2017 [Member] Incident Year 2018 [Member] Incident Year 2018 [Member] Incident Year 2018 [Member] Incident Year 2019 [Member] Incident Year 2019 [Member] Incident Year 2019 [Member] Cumulative Incurred Claims [Line Items] Liability for Claims and Claims Adjustment Expense [Line Items] Cumulative Incurred Claims Liability for Unpaid Claims and Claims Adjustment Expense, Reported Claims, Amount Claims Reserve Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount Cumulative Number Of Reported Claims Loss Contingency, Pending Claims, Number Prospective Adoption of New Accounting Pronouncements [Table] Prospective Adoption of New Accounting Pronouncements [Table] Maximum [Member] Maximum [Member] Prospective Adoption of New Accounting Pronouncements [Axis] Prospective Adoption of New Accounting Pronouncements [Axis] Accounting Guidance [Domain] Accounting Guidance [Domain] Adjustments for New Accounting Pronouncement [Member] Adjustments for New Accounting Pronouncement [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Loans Receivable and related Allowance for Credit Losses [Member] Loans Receivable and the related Allowance for Credit Losses [Member] Loans Receivable and the related Allowance for Credit Losses [Member] Allowance for Credit Losses [Member] Allowance for Credit Losses [Member] Allowance for Credit Losses [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Annual Net Income Impact [Member] Annual Net Income Impact [Member] Annual Net Income Impact Quarterly Net Income Impact [Member] Quarterly Net Income Impact [Member] Quarterly Net Income Impact [Member] Item Effected [Line Items] Item Effected [Line Items] New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Write Off Policy Cap Percentage Based On Future Cash Flows WriteOffPolicyCapPercentageBasedOnFutureCashFlows WriteOffPolicyCapPercentageBasedOnFutureCashFlows Financing Receivable Credit Quality Indicators [Table Text Block] Financing Receivable Credit Quality Indicators [Table Text Block] Schedule Of Percentage Of Consumer Loans Assigned Based On Unit and Dollar Volumes Schedule Of Percentage Of Consumer Loans Assigned Based On Unit Volumes [Table Text Block] Schedule Of Percentage Of Consumer Loans Assigned Based On Unit Volumes Table Text Block SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] Percentage Payment by Period [Table] Percentage Payment by Period [Table] Percentage Payment by Period [Table] Percentage Percentage Payment by Period [Axis] Percentage Percentage Payment by Period [Axis] Percentage Percentage Payment by Period [Axis] Percentage Percentage Payment by Period [Domain] Percentage Percentage Payment by Period [Domain] [Domain] for Percentage Percentage Payment by Period [Axis] Percentage of Claims Paid During Period One [Member] Percentage of Claims Paid During Period One [Member] Percentage of Claims Paid During Period One [Member] Percentage of Claims Paid During Period Two [Member] Percentage of Claims Paid During Period Two [Member] Percentage of Claims Paid During Period Two [Member] Percentage of Claims Paid During Period Three [Member] Percentage of Claims Paid During Period Three [Member] Percentage of Claims Paid During Period Three [Member] Percentage of Claims Paid During Period Four [Member] Percentage of Claims Paid During Period Four [Member] Percentage of Claims Paid During Period Four [Member] Percentage of Claims Paid During Period Five [Member] Percentage of Claims Paid During Period Five [Member] Percentage of Claims Paid During Period Five [Member] Percentage Payment by Period [Line Items] Percentage Payment by Period [Line Items] [Line Items] for Percentage Payment by Period [Table] Payout of Incurred Claims Payout of Incurred Claims Payout of Incurred Claims Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Maximum outstanding balance Line of Credit Facility, Maximum Amount Outstanding During Period Average outstanding balance Line of Credit Facility, Average Outstanding Amount Common shares Weighted Average Number of Shares Issued, Basic Vested restricted stock units Weighted Average Number of Shares, Restricted Stock Basic number of weighted average shares outstanding Weighted Average Number of Shares Outstanding, Basic Dilutive effect of restricted stock and restricted stock units Dilutive Securities Restricted Stock And Restricted Stock Units Dilutive securities restricted stock and restricted stock units. Weighted average shares outstanding: Diluted Weighted Average Number of Shares Outstanding, Diluted Restricted stock outstanding excluded from calculation of diluted net income per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Income Statement [Abstract] Revenues [Abstract] Revenues [Abstract] Finance Charges Revenue Finance Charges Revenue Finance Charges Revenue Premiums earned Premiums Earned, Net Total revenue Costs and expenses [Abstract] Costs and Expenses [Abstract] Salaries and wages Labor and Related Expense General and administrative General and Administrative Expense Sales and marketing Selling and Marketing Expense Provision for credit losses Interest Interest Expense Provision for claims Policyholder Benefits and Claims Incurred, Net Total costs and expenses Costs and Expenses Income before provision for income taxes Provision for income taxes Income Tax Expense (Benefit) Net income Net income per share [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Basic Diluted Weighted average Shares Outstanding [Abstract] Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Basic Diluted Outstanding, Nonvested as of December 31 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Outstanding, Nonvested as of December 31 Weighted Average Grant-Date Fair Value Per Share, Non-vested as of December 31 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value Per Share, Nonvested, Granted Weighted Average Grant-Date Fair Value Per Share, Nonvested, Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value Per Share, Nonvested, Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value Per Share, Non-vested as of December 31 Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent State income taxes Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Effective Income Tax Rate Reconciliation, Deduction, Percent Effective Income Tax Rate Reconciliation, Deduction, Percent Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective tax rate Effective Income Tax Rate Reconciliation, Percent Current provision for income taxes, Federal Current Federal Tax Expense (Benefit) Current provision for income taxes, State Current State and Local Tax Expense (Benefit) Current provision for income taxes Current Income Tax Expense (Benefit) Deferred provision for income taxes, Federal Deferred Federal Income Tax Expense (Benefit) Deferred provision for income taxes, State Deferred State and Local Income Tax Expense (Benefit) Deferred provision for income taxes Deferred Income Tax Expense (Benefit) Interest Unrecognized Tax Benefits, Interest on Income Taxes Expense Unrecognized Tax Benefits, Income Tax Penalties Expense Unrecognized Tax Benefits, Income Tax Penalties Expense Interest and penalties expense (benefit) Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Provision for income taxes Equity [Abstract] Schedule Of Stock Repurchases Class of Treasury Stock [Table Text Block] Balance, beginning of period Transfers Allowance for Loan and Lease Losses, Adjustments, Other Write-offs Allowance for Loan and Lease Losses, Write-offs Recoveries Allowance for Loan and Lease Loss, Recovery of Bad Debts Balance, end of period Restricted Securities Available For Sale Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event [Line Items] Subsequent Event [Line Items] Reinsurance [Table] Reinsurance [Table] Reinsurance [Table] Trust Assets And Reinsurance Liabilities [Axis] Trust Assets And Reinsurance Liabilities [Axis] Trust Assets And Reinsurance Liabilities Axis Trust Assets And Reinsurance Liabilities [Domain] Trust Assets And Reinsurance Liabilities [Domain] Trust Assets And Reinsurance Liabilities Domain Trust Assets [Member] Trust Assets [Member] Trust Assets Member Unearned Premium [Member] Unearned Premium [Member] Unearned Premium Member Claims Reserve [Member] Claims Reserve [Member] Claims Reserve Member Reinsurance [Line Items] Reinsurance [Line Items] [Line Items] for Reinsurance [Table] Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Corporate bonds [Member] Corporate Bond Securities [Member] US Government and agency securities [Member] US Government Agencies Debt Securities [Member] Asset-backed Securities [Member] Asset-backed Securities [Member] Mortgage-backed securities [Member] Collateralized Mortgage Backed Securities [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Cost Available-for-sale Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax Total restricted securities available for sale Property, Plant and Equipment [Abstract] Property And Equipment Property, Plant and Equipment Disclosure [Text Block] Schedule Of Comparison Of The Carrying Value And Estimated Fair Value Of These Financial Instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Schedule Of Assets And Liabilities, Measured At Fair Value On A Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Schedule Of Terms Of Interest Rate Cap Agreements Schedule of Interest Rate Derivatives [Table Text Block] Schedule Of Effect Of Derivative Instruments Not Designated As Hedging Instruments In Consolidated Statements Of Income Derivatives Not Designated as Hedging Instruments [Table Text Block] Number of consumers required to group advances Number Of Consumers Required To Group Advances Number Of Consumers Required To Group Advances Number of Consumer Loans assigned to receive accelerated Dealer Holdback payment Number Of Consumer Loans Assigned To Receive Accelerated Dealer Holdback Payment Number Of Consumer Loans Assigned To Receive Accelerated Dealer Holdback Payment Servicing fee percentage in collections Service Fee Income As Percentage Of Collections Service fee income as a percentage of collections. Number Of Consumer Loans Assigned To Receive Dealer Holdback Payment Number Of Consumer Loans Assigned To Receive Dealer Holdback Payment Number Of Consumer Loans Assigned To Receive Dealer Holdback Payment One-time enrollment fee in program Revenue From Enrollment And Registration Fees In Program Revenue From Enrollment And Registration Fees In Program Percentage of enrollment fee of first accelerated dealer holdback payment Percentage Of Revenue From Enrollment And Registration Fees In Program Percentage Of Revenue From Enrollment And Registration Fees In Program Cumulative Paid Claims [Table] Cumulative Paid Claims [Table] Cumulative Paid Claims [Table] Cumulative Paid Claims [Line Items] Cumulative Paid Claims [Line Items] [Line Items] for Cumulative Paid Claims [Table] Cumulative Paid Claims Cumulative Paid Claims Cumulative Paid Claims Class of Treasury Stock [Table] Class of Treasury Stock [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Open Market [Member] Open Market [Member] Open Market [Member] Other [Member] Other Stock Repurchase Program [Member] Other Stock Repurchase Program [Member] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Increase in number of shares authorized for repurchase Stock Repurchase Program Number Of Shares Authorized To Be Repurchased Increase Stock Repurchase Program Number Of Shares Authorized To Be Repurchased Increase Number of shares authorized for repurchase Stock Repurchase Program, Number of Shares Authorized to be Repurchased Common stock repurchased, shares Common stock repurchased, value Schedule Of Property And Equipment Property, Plant and Equipment [Table Text Block] Other Assets [Member] Other Assets [Member] Secured financings [Member] Secured financings [Member] Secured financings [Member] Unamortized Debt Issuance Costs Unamortized Debt Issuance Expense Unamortized Discount Debt Instrument, Unamortized Discount Debt Instrument, Carrying Amount Debt Instrument, Fair Value Disclosure Debt Instrument, Principal Outstanding Debt Instrument, Principal Outstanding Debt Instrument, Principal Outstanding Schedule Of Reinsurance Activity Schedule Of Reinsurance Activity [Table Text Block] The tabular disclosure pertaining to the existence, magnitude and information about insurance that has been ceded to or assumed from another insurance company, including the methodologies and assumptions used in determining recorded amounts. Schedule Of Trust Assets And Reinsurance Liabilities Schedule Of Trust Assets And Reinsurance Liabilities [Table Text Block] Schedule Of Trust Assets And Reinsurance Liabilities Table Text Block Cumulative Incurred Claims Schedule of Liability for Unpaid Claims and Claims Adjustment Expense [Table Text Block] Cumulative Paid Claims Cumulative Paid Claims [Table Text Block] [Table Text Block] for Cumulative Paid Claims [Table] Percentage Payout Of Incurred Claims Percentage Payout Of Incurred Claims [Table Text Block] [Table Text Block] for Percentage Payout Of Incurred Claims [Table] Loan Pool Performance Meets Or Exceeds Initial Estimates [Member] Loan Pool Performance Meets Or Exceeds Initial Estimates [Member] Loan Pool Performance Meets Or Exceeds Initial Estimates [Member] Loan Pool Performance Less Than Initial Estimates [Member] Loan Pool Performance Less Than Initial Estimates [Member] Loan Pool Performance Less Than Initial Estimates [Member] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Estimated Fair Value, Less than 12 Months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Gross Unrealized Losses, Less than 12 Months Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Estimated Fair Value,12 Months or More Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Gross Unrealized Losses, 12 Months or More Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Total Estimated Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Total Gross Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Summary Of Restricted Stock Activity Schedule Of Share-Based Compensation, Restricted Stock, Activity [Table Text Block] Schedule Of Share-Based Compensation, Restricted Stock, Activity [Table Text Block] Summary Of Restricted Stock Units Activity Share-based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Schedule Of Stock Based Compensation Expense Share-based Payment Arrangement, Cost by Plan [Table Text Block] Schedule Of Future Share-Based Compensation Cost Schedule Of Compensation Cost For Share Based Payment Arrangements Expected Future Compensation Cost By Plan [Table Text Block] Schedule Of Compensation Cost For Share Based Payment Arrangements Expected Future Compensation Cost By Plan [Table Text Block] Net Income Per Share Earnings Per Share [Text Block] Balance, beginning of period Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield New Consumer Loan assignments Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Additions Accretion Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion Provision for credit losses Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications (to) from Nonaccretable Difference Forecast changes Certain Loans Acquired In Transfer Accounted For As Loans Accretable Yield Reclassifications From Nonaccretable Difference Forecast Changes Change in the estimate of cash flows expected to be collected, after acquisition of a loan, which results in an increase in accretable yield (for example, if actual cash flows are significantly greater than previously expected). This relates to loans with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. Transfers Certain Loans Acquired In Transfer Accounted For As Loans Accretable Yield Transfers Certain Loans Acquired In Transfer Accounted For As Loans Accretable Yield Transfers Balance, end of period Schedule Of Loans Receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Summary Of Changes In Loans Receivable Schedule Of Changes In Accounts Notes Loans And Financing Receivable [Table Text Block] Schedule Of Changes In Accounts Notes Loans And Financing Receivable [Table Text Block] Summary Of Changes In Accretable Yield Summary Of Changes In Accretable Yield [Table Text Block] Summary of changes in the accretable yield. Summary Of Information Related To New Consumer Loan Assignments Schedule Of New Consumer Loan Assignments [Table Text Block] Schedule of new consumer loan assignments. Schedule Of Consumer Loans Forecasted Collection Percentage Schedule Of Consumer Loans Forecasted Collection Percentage [Text Block] Schedule Of Consumer Loans Forecasted Collection Percentage [Text Block] Schedule Of Consumer Loans Performance Schedule Of Consumer Loans Performance [Table Text Block] Schedule Of Consumer Loans Performance [Table Text Block] Summary Of Changes In Allowance For Credit Losses Financing Receivable, Allowance for Credit Loss [Table Text Block] Stock-based compensation expense Summary Of Significant Accounting Policies Significant Accounting Policies [Text Block] Schedule Of Quarterly Financial Data Quarterly Financial Information [Table Text Block] Lease Commitments Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Segment Reporting [Abstract] Business Segment And Other Information Segment Reporting Disclosure [Text Block] Number of Operating Segments Number of Operating Segments Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Domain] Timing of Transfer of Good or Service [Domain] Transferred over Time [Member] Transferred over Time [Member] Transferred at Point in Time [Member] Transferred at Point in Time [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Third Party Providers [Member] Third Party Providers [Member] Third Party Providers [Member] Dealers [Member] Dealers [Member] Dealers [Member] Stock Repurchases Stock Repurchases [Text Block] The entire disclosure for an entity's stock repurchases, including the description of the share repurchase program authorized by an entity's board of directors, the number of shares repurchased, the cost of the shares repurchased, the remaining maximum dollar value of shares available for repurchase under the program, and other information necessary to a fair presentation. Balance, beginning of period New Consumer Loan assignments New Consumer Loan Assignments New consumer loan assignments Principal collected on Loans receivable Accelerated Dealer Holdback payments Dealer Holdback payments Transfers Loans And Leases Receivable Transfers Loans and leases receivable transfers. Balance, end of period Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Principal Debt Outstanding Schedule of Principal Debt Outstanding [Table Text Block] Schedule of Principal Debt Outstanding [Table Text Block] Schedule Of General Information Of Financing Transaction Schedule of Debt [Table Text Block] Schedule Of Additional Information Related To Debt Instruments Schedule Of Additional Information Related To Debt Instruments [Table Text Block] Schedule Of Additional Information Related To Debt Instruments [Table Text Block] Summary Of Debt Schedule of Long-term Debt Instruments [Table Text Block] Summary of Term ABS Debt ScheduleOfAssetBackedDebtInstrumentsTextBlock [Table Text Block] ScheduleOfAssetBackedDebtInstrumentsTextBlock [Table Text Block] Scheduled Principal Maturities Of Debt Schedule of Maturities of Long-term Debt [Table Text Block] ASSETS: Assets [Abstract] Loans receivable (including $1.4 from affiliates as of December 31, 2016) Loans receivable, net Property and equipment, net Property, Plant and Equipment, Net Income taxes receivable Income Taxes Receivable Other assets Other Assets Total Assets Assets LIABILITIES AND SHAREHOLDERS' EQUITY: Liabilities and Equity [Abstract] Liabilities: Liabilities [Abstract] Revolving secured line of credit Secured financing Deferred income taxes, net Deferred Income Tax Liabilities, Net Income taxes payable Accrued Income Taxes Total Liabilities Liabilities Shareholders' Equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Shareholders' Equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.01 par value, 1,000,000 shares authorized, none issued Preferred Stock, Value, Issued Common stock, $0.01 par value, 80,000,000 shares authorized, 18,352,779 and 18,972,558 shares issued and outstanding as of December 31, 2019 and December 31, 2018, respectively Common Stock, Value, Issued Paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total Shareholders' Equity Total Liabilities and Shareholders' Equity Liabilities and Equity Loans Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Contractual net cash flows at the time of assignment Loans Receivable Contractual Net Cash Flows At Assignment Loans Receivable Contractual Net Cash Flows At Assignment Expected net cash flows at the time of assignment Loans Receivable Expected Net Cash Flows At Assignment Loans Receivable Expected Net Cash Flows At Assignment Fair value at the time of assignment Loans Receivable Fair Value Of Net Cash Flows At Assignment Loans Receivable Fair Value Of Net Cash Flows At Assignment Derivative [Table] Derivative [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] 5.50% Cap Interest Rate [Member] Five Point Five Percent Cap Interest Rate [Member] 5.5% Cap Interest Rate [Member] 6.50% Cap Interest Rate [Member] Six Point Five Percent Cap Interest Rate [Member] Six Point Five Percent Cap Interest Rate [Member] Additional 6.50% Cap Interest Rate [Member] Additional Six Point Five Percent Cap Interest Rate [Member] Additional Six Point Five Percent Cap Interest Rate [Member] Second Additional 6.50% Cap Interest Rate [Member] Second Additional Six Point Five Percent Cap Interest Rate [Member] Second Additional Six Point Five Percent Cap Interest Rate [Member] 5.00% Cap Interest Rate [Member] Five Percent Cap Interest Rate [Member] 5% Cap Interest Rate [Member] Derivative [Line Items] Derivative [Line Items] Derivative, Notional Amount Derivative, Notional Amount Cap Interest Rate Derivative, Cap Interest Rate Interest rate swap fair value Derivative Asset, Fair Value, Amount Not Offset Against Collateral Percentage of first accelerated Dealer Holdback payment retained Payment Holdback Percentage Payment Holdback Percentage Fair Value Of Financial Instruments Fair Value Disclosures [Text Block] Land and land improvements Land and Land Improvements Building and improvements Buildings and Improvements, Gross Data processing equipment and software Data Processing Equipment And Software Data Processing Equipment And Software Office furniture and equipment Furniture and Fixtures, Gross Leasehold improvements Leasehold Improvements, Gross Total property and equipment Property, Plant and Equipment, Gross Less: Accumulated depreciation on property and equipment Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, Plant and Equipment, Net, Total Schedule of Cash and Cash Equivalents [Table Text Block] Schedule of Cash and Cash Equivalents [Table Text Block] Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Interest Expense [Member] Interest Expense [Member] Interest Rate Caps [Member] Interest Rate Cap [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Not Designated as Hedging Instrument [Member] Not Designated as Hedging Instrument [Member] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Amount of (Loss) / Gain Recognized in Income on Derivatives Derivative, Gain (Loss) on Derivative, Net Allowance for credit losses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Deferred state net operating loss Deferred Tax Assets, Operating Loss Carryforwards, State and Local Other, net Deferred Tax Assets, Other Total deferred tax assets Deferred Tax Assets, Gross Valuation of Loans receivable Deferred Tax Liabilities, Financing Arrangements Deferred Loan origination costs Deferred Tax Liabilities, Deferred Expense, Debt Issuance Costs Other, net Deferred Tax Liabilities, Other Total deferred tax liabilities Deferred Tax Liabilities, Net Deferred income taxes, net Outstanding, as of December 31 Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number Granted Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted Converted Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures Outstanding, as of December 31 Vested Weighted Average Grant-Date Fair Value Per Share, Outstanding as of December 31 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Weighted Average Grant Date Fair Value The weighted average fair value of awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. Weighted Average Grant-Date Fair Value Per Share, Nonvested, Converted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Converted, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Converted, Weighted Average Grant Date Fair Value Weighted Average Grant-Date Fair Value Per Share, Outstanding as of December 31 Weighted Average Grant-Date Fair Value Per Share, Vested as of December 31 Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Weighted Average Grant Date Fair Value Share based compensation arrangement by share based payment award equity instruments other than options vested weighted average grant date fair value. Aggregate Intrinsic Value, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Aggregate Intrinsic Value, Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested Weighted Average Remaining Contractual Term, Outstanding Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Weighted Average Remaining Contractual Term, Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Weighted Average Remaining Contractual Terms Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested, Weighted Average Remaining Contractual Terms Net assumed written premiums Assumed Premiums Written Net premiums earned Amortization of capitalized acquisition costs Amortization of Acquisition Costs Quarterly Financial Data Quarterly Financial Information [Text Block] Within one year, cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Over one year to five years, cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Over five years to ten years, cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost Over ten years, cost Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost Total restricted securities available for sale, cost Debt Securities, Available-for-sale, Amortized Cost Within one year, estimated fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Over one year to five years, estimated fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Over five years to ten years, estimated fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value Over ten years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value Total restricted securities available for sale, estimated fair value Age of Consumer Loans contractual payments due with no forecasted future net cash flows Period After Consumer Loans With No Forecasted Future Net Cash Flows Period After Consumer Loans With No Forecasted Future Net Cash Flows Impact of Forecast Change on Credit Losses Impact of Forecast Change on Credit Losses Impact of Forecast Change on Credit Losses Impact of Forecast Change on Finance Charges Impact of Forecast Change on Finance Charges Impact of Forecast Change on Finance Charges Impact of Forecast Change on Net Income Impact of Forecast Change on Net Income Impact of Forecast Change on Net Income Impact of Forecast Change on Loan Portfolio Yield Impact of Forecast Change on Loan Portfolio Yield Impact of Forecast Change on Loan Portfolio Yield