Property, Plant and Equipment [Abstract] Schedule Of Property And Equipment Property, Plant and Equipment [Table Text Block] Fair Value Disclosures [Abstract] 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] Receivables [Abstract] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] 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] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Transfers Loans And Leases Receivable Transfers Loans and leases receivable transfers. 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Previously Reported [Member] Previously Reported [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Restricted Cash Increase (Decrease) in Restricted Cash Net Cash Provided by (Used in) Investing Activities Net Cash Provided by (Used in) Investing Activities Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Share-based Compensation [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Restricted Stock 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Party Loan Activity Schedule of Related Party Transactions [Table Text Block] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Income Taxes Income Tax Disclosure [Text Block] Document And Entity Information [Abstract] Document and Entity Information (Abstract) Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Public Float Entity Public Float Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Small Business Entity Small Business Debt Disclosure [Abstract] Debt Debt 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] 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 SEC Schedule, 12-17, Insurance Companies, Reinsurance [Abstract] Percentage 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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 Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] 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 Conversion of Stock, Shares 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 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 Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance 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 Deferred Income Tax Liabilities, Net Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash and cash equivalents Restricted Cash and Cash Equivalents Lease Commitments Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Term ABS 2015-1 [Member] TermAssetBackedSecuredFinancingsTwoThousandFifteenOne [Member] TermAssetBackedSecuredFinancingsTwoThousandFifteenOne [Member] Term ABS 2015-2 [Member] TermAssetBackedSecuredFinancingsTwoThousandFifteenTwo [Member] TermAssetBackedSecuredFinancingsTwoThousandFifteenTwo [Member] Term ABS 2016-2 [Member] TermAssetBackedSecuredFinancingsTwoThousandSixteenTwo [Member] TermAssetBackedSecuredFinancingsTwoThousandSixteenTwo [Member] Term ABS 2016-3 [Member] TermAssetBackedSecuredFinancingsTwoThousandSixteenThree [Member] TermAssetBackedSecuredFinancingsTwoThousandSixteenThree [Member] Term ABS 2017-1 [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenOne [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenOne [Member] Term ABS 2017-2 [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenTwo [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenTwo [Member] Term ABS 2017-3 [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenThree [Member] TermAssetBackedSecuredFinancingsTwoThousandSeventeenThree [Member] Term ABS 2018-1 [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenOne [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenOne [Member] Term ABS 2018-2 [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenTwo [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenTwo [Member] Term ABS 2018-3 [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenThree [Member] TermAssetBackedSecuredFinancingsTwoThousandEighteenThree [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Debt financing close date Debt financing close date Debt financing close date Net Book Value Of Loans Pledged As Collateral Net Book Value Of Loans Pledged As Collateral Net Book Value Of Loans Pledged As Collateral 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 Schedule of Credit Losses Related to Financing Receivables, Current and Noncurrent [Table Text Block] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Prime Rate [Member] Prime Rate [Member] LineofCreditTwoThousandNineteen [Member] LineofCreditTwoThousandNineteen [Member] LineofCreditTwoThousandNineteen [Member] Revolving Secured Line Of Credit [Member] Line of Credit [Member] Revolving Secured Line of Credit Future Maximum Borrowing Capacity [Member] Line of Credit Future Maximum Borrowing Capacity [Member] Line of Credit Future Maximum Borrowing Capacity [Member] Warehouse Facilities [Member] Warehouse Facilities [Member] Warehouse facilities member. Warehouse Facility VI [Member] Warehouse Facility VI [Member] WarehouseFacilityVI [Member] 2017 Senior Notes [Member] Two Thousand Seventeen Senior Notes [Member] Two Thousand Seventeen Senior Notes [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] Mortgage [Member] Mortgages [Member] Debt Instrument, Issuance Date Debt Instrument, Issuance Date Debt maturity date Debt Instrument, Maturity Date Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Line of credit facility Line of Credit Facility, Maximum Borrowing Capacity Percentage of net book value of loans Percentage Of Net Book Value Of Loans Percentage of net book value of loans, maximum. 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 Repayments of Senior Debt Redemption price, percentage of principal amount redeemed Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Loss on extinguishment of debt Gain (Loss) on Extinguishment of Debt Debt covenants Debt Instrument Covenant Net Income For Past Two Quarters Debt Instrument Covenant Net Income For Past Two Quarters Proceeds from issuance of senior notes Proceeds from Issuance of Senior Long-term Debt Interest rate Debt Instrument, Interest Rate, Effective Percentage Equity [Abstract] 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. 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 Maximum outstanding balance Line of Credit Facility, Maximum Amount Outstanding During Period Average outstanding balance Line of Credit Facility, Average Outstanding Amount Net Income Per Share Earnings Per Share [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] Investments, Debt and Equity Securities [Abstract] Restricted Securities Available For Sale Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Other Income and Expenses [Abstract] Other Income and Other Expense Disclosure [Text Block] Other Income and Other Expense Disclosure [Text Block] Depreciation Depreciation Secured Debt [Member] Secured Debt [Member] Term ABS Financing [Member] Term ABS Financing [Member] Term ABS Financing [Member] Senior Notes [Member] Senior Notes [Member] 2019 Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months 2020 Long-term Debt, Maturities, Repayments of Principal in Year Two 2021 Long-term Debt, Maturities, Repayments of Principal in Year Three 2022 Long-term Debt, Maturities, Repayments of Principal in Year Four 2023 Long-term Debt, Maturities, Repayments of Principal in Year Five After 2023 Long-term Debt, Maturities, Repayments of Principal after Year Five Total Long-term Debt, Gross Stock-Based Compensation Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Principal balance outstanding Long-term Line of Credit Principal balance outstanding Senior Notes, Noncurrent Principal balance outstanding Amount 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Income Total revenue Revenues 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 Provision for Loan and Lease Losses Interest Interest Expense Loss on extinguishment of debt Total costs and expenses Costs and Expenses Income before provision for income taxes Provision for income taxes Net income Net Income (Loss) Attributable to Parent Net income per share [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Basic Earnings Per Share, Basic Diluted Earnings Per Share, Diluted Weighted average Shares Outstanding [Abstract] Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Basic Weighted Average Number of Shares Outstanding, Basic Diluted Weighted Average Number of Shares Outstanding, Diluted Statement of Financial Position [Abstract] Preferred stock, par value 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[Member] Incident Year 2018 [Member] Incident Year 2018 [Member] Incident Year 2018 [Member] 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 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] 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 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 Restricted stock outstanding excluded from calculation of diluted net income per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Data Quarterly Financial Information [Text Block] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] 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] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Ancillary Product Profit Sharing [Member] Ancillary Product Profit Sharing Income [Member] Ancillary Product Profit Sharing [Member] Remarketing Fees [Member] Remarketing Fees [Member] Remarketing Fees [Member] GPS-SID Fees [Member] GPS-SID Fees [Member] GPS-SID Fees [Member] Interest Income [Member] Interest [Member] Interest [Member] Dealer Enrollment Fees [Member] Dealer Enrollment Fees [Member] Dealer Enrollment Fees [Member] Dealer Support Products And Services [Member] Dealer Support Products And Services [Member] Dealer Support Products And Services [Member] Other [Member] Other [Member] Other [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] One-time enrollment fee in program Revenue From Enrollment And Registration Fees In Program Revenue From Enrollment And Registration Fees In Program Percentage of first accelerated Dealer Holdback payment retained Payment Holdback Percentage Payment Holdback Percentage Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Affiliated Dealer Activity [Member] Affiliated Entity [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Dealer Loan revenue Revenue from Related Parties Dealer Loan revenue, percentage Percentage Of Related Party Transaction Revenues From Transaction Percentage Of Related Party Transaction Revenues From Transaction New Consumer Loan assignments 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. New Consumer Loan assignments, percentage Percentage Of Advances To Dealers Percentage Of Advances To Dealers Accelerated Dealer Holdback payments 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. Accelerated Dealer Holdback payments, percentage Percentage Of Accelerated Payments Of Dealer Holdback Percentage Of Accelerated Payments Of Dealer Holdback Dealer Holdback payments 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. Dealer Holdback payments, percentage Percentage Of Payments Of Dealer Holdback Percentage Of Payments Of Dealer Holdback Loans Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] US Government and agency securities [Member] US Government Agencies Debt Securities [Member] Corporate bonds [Member] Corporate Bond 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 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 Unrecognized tax benefits at January 1 Unrecognized Tax Benefits Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Reductions for tax positions of prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Reductions as a result of a lapse of the statute of limitations Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations Unrecognized tax benefits at December 31 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] Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities Revolving secured line of credit Senior notes Deferred income taxes, 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, $.01 par value, 1,000,000 shares authorized, none issued Preferred Stock, Value, Issued Common stock, $.01 par value, 80,000,000 shares authorized, 19,877,381 and 20,132,972 shares issued and outstanding as of December 31, 2016 and December 31, 2015, 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 Stockholders' Equity Attributable to Parent Total Liabilities and Shareholders' Equity Liabilities and Equity Revenue Net income Net income per share: Basic Net income per share: Diluted Derivative And Hedging Instruments Derivative Instruments and Hedging Activities Disclosure [Text Block] Principles Of Consolidation Consolidation, Policy [Policy Text Block] Business Segment Information Segment Reporting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Cash And Cash Equivalents And Restricted Cash And Cash Equivalents Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Restricted Securities Available For Sale Restricted Available-For-Sale Securities [Policy Text Block] Restricted Available-For-Sale Securities [Policy Text Block] Loans Receivable And Allowance For Credit Losses Policy Loans Receivable, Policy [Policy Text Block] Property And Equipment Property, Plant and Equipment, Policy [Policy Text Block] Deferred Debt Issuance Costs Debt Related Commitment Fees And Debt Issuance Costs Policy Text Block Debt Related Commitment Fees And Debt Issuance Costs Policy Text Block Derivative Instruments Derivatives, Policy [Policy Text Block] Finance Charges Finance Charges Policy [Policy Text Block] Finance Charges Policy [Policy Text Block] Reinsurance Reinsurance Accounting Policy [Policy Text Block] Stock-Based Compensation Plans Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Employee Benefit Plan Compensation Related Costs, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Advertising Costs Advertising Costs, Policy [Policy Text Block] New Accounting Updates New Accounting Pronouncements, Policy [Policy Text Block] Subsequent Events Subsequent Events, Policy [Policy Text Block] 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] 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] 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 Cash Flow, Supplemental Disclosures [Text Block] Cash Flow, Supplemental Disclosures [Text Block] Schedule of Cash and Cash Equivalents [Table Text Block] Schedule of Cash and Cash Equivalents [Table Text Block] 2019 Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Next Twelve Months Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs Next Twelve Months 2020 Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Two Years Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Two Years 2021 Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Three Years Employee Service Share Based Compensation Estimated Allocation Of Recognized Period Costs In Three Years 2022 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 2023 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 Related Party Transactions Related Party Transactions Disclosure [Text Block] Statement of Cash Flows [Abstract] Cash Flows From Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Provision for credit losses Amortization Amortization of Debt Issuance Costs and Discounts Increase (Decrease) in Deferred Income Taxes Increase (Decrease) in Deferred Income Taxes Stock-based compensation Share-based Compensation 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] Increase in restricted cash and cash equivalents 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 Purchases of Consumer Loans Payments to Acquire Loans Receivable Accelerated payments of Dealer Holdback Payments of Dealer Holdback Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Net cash 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 mortgage note Proceeds from Issuance of First Mortgage Bond Repayments of senior notes Payments of debt issuance costs and debt issuance costs Payments of Debt Issuance Costs Repurchase of common stock Payments for Repurchase of Common Stock Tax benefits from stock-based compensation plans Excess Tax Benefit from Share-based Compensation, Financing Activities Other financing activities Proceeds from (Payments for) Other Financing Activities Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase in cash and cash equivalents and restricted cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Supplemental Cash Flow Information [Abstract] Supplemental Cash Flow Information [Abstract] Cash paid during the period for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Cash paid during the period for income taxes Income Taxes Paid, Net Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Carrying Amount [Member] Reported Value Measurement [Member] Estimated Fair Value [Member] Estimate of Fair Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Assets, Fair Value Disclosure [Abstract] Assets, Fair Value Disclosure [Abstract] Liabilities, Fair Value Disclosure [Abstract] Liabilities, Fair Value Disclosure [Abstract] Stock-based compensation expense 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] 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] Property And Equipment Property, Plant and Equipment Disclosure [Text Block] Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] 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] Computer Software, Intangible Asset [Member] Office Furniture And Equipment [Member] Office Equipment [Member] Leasehold Improvements [Member] Leasehold Improvements [Member] Software Development [Member] Software Development [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Member] Cash and Cash Equivalents [Member] Restricted Cash And Cash Equivalents [Member] Restricted Cash And Cash Equivalents [Member] Restricted Cash And Cash Equivalents Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Summary Of Significant Accounting Policies [Line Items] Number of Portfolio Segments Number of Portfolio Segments Number of Portfolio Segments Number of Reportable Segments Number of Reportable Segments Uninsured cash and cash equivalents Cash, Uninsured Amount Monthly fee charged Dealer in Portfolio Program Monthly Fee Portfolio Program Monthly Fee Portfolio Program Period after Consumer Loan assignment that Dealer Loans written off Period After Determination Dealer Loan Write Off Period After Determination Dealer Loan Write Off Period after month of purchase that Purchased Loans written off Period After Determination Purchased Loan Write Off Period After Determination Purchased Loan Write Off Estimated useful lives Property, Plant and Equipment, Estimated Useful Lives Threshold to determine likelihood of being sustained Threshold To Determine Probability Threshold To Determine Probability Employer matching contribution, match percentage Defined Contribution Plan, Employer Matching Contribution, Percent of Match Matching contribution Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Employer matching contribution, additional match percentage DefinedContributionPlanAdditionalEmployerMatchingContributionPercentofMatch DefinedContributionPlanAdditionalEmployerMatchingContributionPercentofMatch Additional matching contribution DefinedContributionPlanAdditionalEmployerMatchingContributionPercent DefinedContributionPlanAdditionalEmployerMatchingContributionPercent Maximum matching contribution Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Recognized compensation expense Defined Contribution Plan, Cost Advertising expense Advertising Expense 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 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. 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 Deferred Tax Assets, Operating Loss Carryforwards Deferred Tax Assets, Operating Loss Carryforwards Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Deferred Tax Assets, Valuation Allowance 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 Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Incentive Plan [Member] Incentive Plan [Member] Incentive Plan [Member] Minimum [Member] Minimum [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Fifteen Year Vesting [Member] Fifteen Year Vesting [Member] [Member] Fifteen Year Vesting [Member] [Member] Ten Year Vesting [Member] Ten Year Vesting [Member] Ten Year Vesting [Member] Five Year Vesting [Member] Five Year Vesting [Member] Five Year Vesting [Member] Three Year Vesting [Member] Three Year Vesting [Member] Three Year Vesting [Member] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Chief Executive Officer [Member] Chief Executive Officer [Member] Number of additional shares authorized for issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Total authorized shares for plan issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Shares available for issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Weighted average fair value of shares granted Fair value of shares vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Restricted stock units converted to common stock, shares Intrinsic value of restricted stock units exercised Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercises in Period, Total Intrinsic Value Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on non-option equity instruments exercised (or share units converted) into shares. Weighted average recognition period Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Credit Score, FICO [Axis] Credit Score, FICO [Axis] Credit Score, FICO [Domain] Credit Score, FICO [Domain] Percentage Of Contracts With FICO Score Lower Than 650 Or No FICO Score [Member] Percentage Of Contracts With FICO Score Lower Than 650 Or No FICO Score [Member] Percentage Of Contracts With FICO Score Lower Than 650 Or No FICO Score [Member] Financing Receivable, Recorded Investment [Line Items] Financing Receivable, Recorded Investment [Line Items] Financing Receivable, Credit Quality, Additional Information Financing Receivable, Credit Quality, Additional Information Schedule Of Restricted Securities Available For Sale Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Schedule Of Restricted Securities Available For Sale By Aging Catagory Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Table Text Block] Schedule Of Cost And Estimated Fair Values Of Debt Securities By Contractual Maturity Investments Classified by Contractual Maturity Date [Table Text Block] Derivative Instruments, Gain (Loss) [Table] Derivative Instruments, Gain (Loss) [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] 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 Reinsurance Reinsurance [Text Block] Schedule Of Quarterly Financial Data Quarterly Financial Information [Table 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] Statement of Comprehensive Income [Abstract] Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax [Abstract] Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax [Abstract] Unrealized gain (loss) on securities, net of tax Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Fair Value Of Financial Instruments Fair Value Disclosures [Text Block] 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 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 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 Stock Repurchased During Period, Shares Common stock repurchased, value Stock Repurchased During Period, Value Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Paid-In Capital [Member] Additional Paid-in Capital [Member] Retained Earnings [Member] Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Balance, shares Balance Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Restricted stock awards, net of forfeitures, shares Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Repurchase of common stock, shares Repurchase of common stock Tax benefits from stock-based compensation plans Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation Balance, shares Balance Description Of Business [Table] Description Of Business [Table] Description Of Business [Table] Payments For Proceeds From Loans Receivable Programs [Axis] Payments For Proceeds From Loans Receivable Programs [Axis] Payments For Proceeds From Loans Receivable Programs Axis Payments For Proceeds From Loans Receivable Programs [Domain] Payments For Proceeds From Loans Receivable Programs [Domain] Payments For Proceeds From Loans Receivable Programs Domain Portfolio Program [Member] Portfolio Program [Member] Portfolio Program Member Purchase Program [Member] Purchase Program [Member] Purchase Program Member Description Of Business [Line Items] Description Of Business [Line Items] Description Of Business [Line Items] Percentage of new consumer loans in unit volume Percentage Of New Consumer Loans In Unit Volume Percentage of new consumer loans in unit volume Percentage of new consumer loans in dollar volume Percentage Of New Consumer Loans In Dollar Volume Percentage of new consumer loans in dollar volume Schedule Of Stock Repurchases Class of Treasury Stock [Table 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 Cumulative Incurred Claims [Table] Liability for Claims and Claims Adjustment Expense [Table] 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 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 Balance, beginning of period Balance, end of period Rent expense Operating Leases, Rent Expense, Net 2018 Operating Leases, Future Minimum Payments, Next Rolling Twelve Months 2019 Operating Leases, Future Minimum Payments, Due in Rolling Year Two 2020 Operating Leases, Future Minimum Payments, Due in Rolling Year Three 2021 Operating Leases, Future Minimum Payments, Due in Rolling Year Four 2022 Operating Leases, Future Minimum Payments, Due in Rolling Year Five Total Operating Leases, Future Minimum Payments Due