Total current assets Business Combination, Recognized Asset Acquired, Asset, Current Proceeds from dealership divestitures Proceeds from Divestiture of Businesses Type of Brand [Domain] Type of Brand [Domain] Type of Brand [Domain] Other current assets Other Current Assets [Member] Property and equipment, net Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment Schedule of Debt Securities, Available-for-Sale Debt Securities, Available-for-Sale [Table Text Block] Property and equipment, net Disposal Group, Including Discontinued Operation, Property, Plant and Equipment Components of Inventory [Axis] Components of Inventory [Axis] Components of Inventory Award Timing Predetermined Award Timing Predetermined [Flag] Floor plan borrowings—non-trade Proceeds From Floor Plan Borrowings Non Trade Borrowings of floorplan notes payable to parties other than the manufacturer of the new vehicle and all floorplan notes payable related to pre-owned vehicles. Gains (losses) on changes in fair value of debt securities, tax expense (benefit) OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, Tax Entity File Number Entity File Number Additional Paid-in Capital Additional Paid-in Capital [Member] Other long-term assets Other Noncurrent Assets [Member] Interest Rate Swap Interest Rate Swap, January 2022 Interest Rate Swap [Member] Reduction to cost of sales Reduction to New Vehicle Cost of Sales by Automobile Manufacturer Incentives Reduction to New Vehicle Cost of Sales by Automobile Manufacturer Incentives Floor plan repayments—divestitures Repayments Of Floor Plan Payables Non Trade Divestitures Repayment of floor plan payables non trade associated with the sale of the related franchise. Tabular List, Table Tabular List [Table Text Block] Basic— Earnings Per Share, Basic [Abstract] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] 2021 BofA Real Estate Facility 2021 BofA Real Estate Facility [Member] 2021 BofA Real Estate Facility Loaners Disposal Group, Including Discontinued Operation, Operating Lease Liabilities Disposal Group, Including Discontinued Operation, Operating Lease Liabilities Franchises acquired Business Combination, Franchises Acquired Business Combination, Franchises Acquired Contract assets, current Contract with Customer, Asset, after Allowance for Credit Loss, Current Schedule of Discontinued Operations and Related Results of Business Disposal Groups, Including Discontinued Operations [Table Text Block] Share Repurchases Share Repurchase Policy [Policy Text Block] Share Repurchase Policy [Policy Text Block] Franchises & Dealerships Sold Franchises & Dealerships Sold [Member] Franchises & Dealerships Sold 5.00% Senior Notes due 2032 Five Point Zero Zero Percent Percent Senior Notes due 2029 [Member] Five Point Zero Zero Percent Percent Senior Notes due 2029 Gross Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Measurement Basis [Axis] Measurement Basis [Axis] Net income (in dollars per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities REVENUE RECOGNITION Revenue from Contract with Customer [Text Block] Interest Rate Swap, February 2026 Interest Rate Swap, February 2026 [Member] Interest Rate Swap, February 2026 Schedule of Segment Reporting Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Inventory Disclosure [Abstract] Inventory Disclosure [Abstract] Interest Rate Swap, July 20 Interest Rate Swap, July 2020 [Member] Interest Rate Swap 1.1 [Member] FINANCIAL INSTRUMENTS AND FAIR VALUE Derivatives and Fair Value [Text Block] Total assets held for sale Disposal Group, Including Discontinued Operation, Assets Components of Inventory [Domain] Component of Inventory [Domain] Component of Inventory [Domain] Schedule of Carrying Amounts of Investment Securities and Fair Values Schedule of Available-for-Sale Securities Reconciliation [Table Text Block] Adjustment to Compensation, Amount Adjustment to Compensation Amount Other receivables Other Trade Accounts Receivable [Member] Other Trade Accounts Receivable [Member] Other current assets Increase (Decrease) in Other Operating Assets Share-based compensation Share-Based Payment Arrangement, Noncash Expense Repurchase of common stock associated with net share settlement of employee share-based awards Repurchase of common stock associated with net share settlement of employee share-based awards Shares Repurchased During Period Associated With share-Based Awards, Value Shares Repurchased During Period Associated With share-Based Awards, Value Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Proceeds from the disposition of assets Proceeds from Sale of Productive Assets Floor plan interest expense Floor Plan interest Expense Interest expense incurred on vehicle floorplan payable trade and non-trade outstanding during the period. Accounts and Financing Receivables [Table] Accounts and Financing Receivables [Table] Finance and insurance, net Finance And Insurance, Net [Member] Finance And Insurance, Net Asset impairments Asset impairments Asset Impairment Charges Total shareholders' equity Beginning balance Ending balance Equity, Attributable to Parent Measurement Frequency [Axis] Measurement Frequency [Axis] Derivative Instruments, Gain (Loss) [Line Items] Derivative Instruments, Gain (Loss) [Line Items] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-Sale [Table] Other comprehensive income (loss) - net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] TCA TCA [Member] TCA Common stock, shares authorized (in shares) Common Stock, Shares Authorized BMW BMW [Member] BMW INTANGIBLE FRANCHISE RIGHTS Indefinite-Lived Franchise Rights New vehicle floor plan facility New Vehicle Floor Plan Facility [Member] New Vehicle Floor Plan Facility [Member] CURRENT ASSETS: Assets, Current [Abstract] Total liabilities and shareholders' equity Liabilities and Equity Recurring Fair Value, Recurring [Member] 2018 Wells Fargo Master Loan Facility 2018 Wells Fargo Master Loan Facility [Member] 2018 Wells Fargo Master Loan Facility [Member] INVESTMENTS Investments Noncurrent Investments Noncurrent Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income Statement Location, by Derivative Instrument Risk [Table] Derivative Instruments, Gain (Loss) [Table] LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] Unrealized (losses) gains on available-for-sale debt securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment and Tax Cover [Abstract] Cover [Abstract] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] ASSETS AND LIABILITIES HELD FOR SALE Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Floor plan notes payable—trade Floor Plan Notes Payable Trade, Gross Floor Plan Notes Payable Trade, Gross Total fair value Debt Securities, Available-for-Sale, Unrealized Loss Position Due after 10 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Operating lease liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating lease liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating lease liabilities Repayments of borrowings Repayments of Secured Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Treasury Stock Treasury Stock, Common [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Domestic Brands Domestic Brands [Member] Domestic Brands [Member] INCOME BEFORE INCOME TAXES Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Amount of surety bond line maintained Amount of Surety Bond Line Maintained Amount of Surety Bond Line maintained in the ordinary course of business. OTHER LONG-TERM LIABILITIES Other Liabilities, Noncurrent Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Operating Segments Operating Segments [Member] Change in fair value of cash flow swaps Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Company Selected Measure Amount Company Selected Measure Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Interest Rate Swap, January 2022 Interest Rate Swap, January 2022 [Member] Interest Rate Swap, January 2022 Income tax benefit (expense) associated with available-for-sale debt securities Comprehensive Income (Loss), Net of Tax, Attributable to Parent Disposal Group Name [Domain] Disposal Group Name [Domain] Name Measure Name Due in 1 year or less Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, Year One Current maturities of operating leases Operating Lease, Liability, Current DEFERRED INCOME TAXES Deferred Income Tax Liabilities, Net Document Fiscal Period Focus Document Fiscal Period Focus Number of dealership locations, sold (in dealership locations) Number Of Dealership Locations, Sold Number Of Dealership Locations, Sold Herb Chambers Dealerships Herb Chambers Dealerships [Member] Herb Chambers Dealerships Award Timing Method Award Timing Method [Text Block] Award Type [Axis] Award Type [Axis] DEFERRED REVENUE Contract with Customer, Liability, Noncurrent Long-term Debt Long-Term Debt Bank of America, N.A. Bank of America, N.A. [Member] Bank of America, N.A. [Member] Total assets Assets Assets Used vehicle retail Used vehicle retail [Member] Used vehicle retail [Member] Trading Symbol Trading Symbol Issuance of common stock, net of forfeitures in connection with share-based payment arrangements (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Entity Address, City or Town Entity Address, City or Town CASH FLOW FROM OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Reduction of new vehicle inventory cost by automobile manufacturer incentives Inventory Adjustments Receivable Type [Axis] Receivable Type [Axis] DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Other segment items Segment Reporting, Other Segment Item, Amount Number of franchises, sold (in franchises) Number of Franchises, Sold Number of Franchises, Sold INVENTORIES Inventory Disclosure [Text Block] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Statement of Income Location, Balance [Domain] Statement of Income Location, Balance [Domain] Restricted Share Units Restricted Stock Units (RSUs) [Member] Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Aggregate purchase price Business Combination, Consideration Transferred 2025 Real Estate Facility 2025 Real Estate Facility [Member] 2025 Real Estate Facility Floor plan notes payable—used non-trade Floor Plan Notes Payable Non Trade, Used, Gross Floor Plan Notes Payable Non Trade, Used, Gross Operating lease right-of-use assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating lease right-of-use assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Operating lease right-of-use assets Stock repurchase program, increase (decrease) in authorized amount Stock Repurchase Program, Increase (Decrease) In Authorized Amount Stock Repurchase Program, Increase (Decrease) In Authorized Amount Entity Emerging Growth Company Entity Emerging Growth Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-Sale [Line Items] Repayments of revolving credit facility Repayments of Lines of Credit Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Less—debt issuance costs Debt Issuance Costs, Net Number of investment categories Number Of Investment Categories Number Of Investment Categories 4.625% Senior Notes due 2029 Four Point Six Two Five Percent Senior Notes due 2029 [Member] Four Point Six Two Five Percent Senior Notes due 2029 Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Business Combination [Domain] Business Combination [Domain] Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Incremental common shares (in shares) Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares Mercedes-Benz; Sprinter Mercedes-Benz; Sprinter [Member] Mercedes-Benz; Sprinter PEO PEO [Member] ACCOUNTS RECEIVABLE Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Schedule of Amortized Cost and Fair Value of TCA's Investment Investments Classified by Contractual Maturity Date [Table Text Block] Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Acquired Including Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Acquired Including Goodwill Changes in operating assets and liabilities, net of acquisitions and divestitures— Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Results Reclassified from Accumulated Other Comprehensive Income/(Loss) to Earnings Debt Securities, Available-for-Sale, Loss Reclassified from Accumulated OCI into Income, Effective Portion Debt Securities, Available-for-Sale, Loss Reclassified from Accumulated OCI into Income, Effective Portion Ford Franchise Ford Franchise [Member] Ford Franchise Retained Earnings Retained Earnings [Member] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Floor plan notes payable offset account Floor Plan Notes Payable Trade, Offsets Floor Plan Notes Payable Trade, Offsets Statement of Income: Income Statement [Abstract] Cash and cash equivalents CASH AND CASH EQUIVALENTS, beginning of period CASH AND CASH EQUIVALENTS, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Guarantee Obligations Guarantee Obligations [Member] Income tax expense Income Tax Expense (Benefit) 12 months or longer, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer Change in fair value of cash flow swaps, tax expense (benefit) Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax Investments, fair value Investments, Fair Value Disclosure Long-term debt, including current portion Long Term Debt and Lease Obligations, Including Unamortized Premium (Discount) Long Term Debt and Lease Obligations, Including Unamortized Premium (Discount) Loaners, net Disposal Group, Including Discontinued Operation, Loaners Disposal Group, Including Discontinued Operation, Loaners Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Floor plan notes payable—new non-trade Floor Plan Notes Payable Non Trade, New, Gross Floor Plan Notes Payable Non Trade, New, Gross Product and Service [Domain] Product and Service [Domain] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Change in fair value of cash flow swaps, net of reclassification adjustment Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Business Combination [Table] Business Combination [Table] Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] OTHER EXPENSES (INCOME): Other Income and Expenses [Abstract] Business Combination, Recognized Asset Acquired and Liability Assumed Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Income tax (expense) benefit associated with cash flow swaps Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax, Parent Floor Plan Notes Payable [Table] Floor Plan Notes Payable [Table] Floor Plan Notes Payable [Table] City Area Code City Area Code ACQUISITIONS AND DIVESTITURES Mergers, Acquisitions and Dispositions Disclosures [Text Block] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Mortgage notes payable bearing interest at fixed rates Mortgages [Member] Components of Inventory [Line Items] Components of Inventory [Line Items] Components of Inventory [Line Items] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Number of assets held-for-sale Number Of Assets Held-For-Sale Number Of Assets Held-For-Sale Schedule of Contract with Customer, Assets Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] CASH FLOW FROM INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Debt instrument, conversion, maximum convertible amount, amount subtracted from contractual total Debt Instrument, Conversion, Maximum Convertible Amount, Amount Subtracted from Contractual Total Debt Instrument, Conversion, Maximum Convertible Amount, Amount Subtracted from Contractual Total Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Operating lease right-of-use assets Disposal Group, Including Discontinued Operation, Operating Lease ROU Assets Disposal Group, Including Discontinued Operation, Operating Lease ROU Assets Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Interest receivable Interest Receivable Disposed of by sale Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] 4.75% Senior Notes due 2030 Four Point Seven Five Percent Senior Notes due 2030 [Member] Four Point Seven Five Percent Senior Notes due 2030 [Member] Proceeds from the sale of debt securities—available-for-sale Proceeds from Sale of Debt Securities, Available-for-Sale Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Other current assets Business Combination, Recognized Asset Acquired, Other Asset, Current Parts and services Parts and Services [Member] Parts and services [Member] GOODWILL Goodwill Goodwill Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Assets held for sale Asset, Held-for-Sale, Not Part of Disposal Group, Current Equity Components [Axis] Equity Components [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Total by maturity Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Fair Value Number of reportable segments Number of Reportable Segments Inventories, net Business Combination, Recognized Asset Acquired, Inventory, Current Supplemental Cash Flow Information [Abstract] Supplemental Cash Flow Information [Abstract] Loaner Vehicle Floorplan Facility Loaner Vehicle Notes Payable - OEMs [Member] Loaner Vehicle Notes Payable - OEMs Amortized Cost Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost Other Performance Measure, Amount Other Performance Measure, Amount Entity Address, State or Province Entity Address, State or Province Total current liabilities Liabilities, Current Real Estate Real Estate [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Individual: Individual [Axis] Other current assets Other Assets, Current Additional paid-in capital Additional Paid in Capital, Common Stock Repurchase of common stock associated with net share settlement of employee share-based awards (in shares) Shares Repurchased During Period Associated With share-Based Awards, Shares Shares Repurchased During Period Associated With share-Based Awards, Shares Net cash provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Results Reclassified from Accumulated Other Comprehensive Income/(Loss) to Earnings Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net Infiniti Infiniti [Member] Infiniti Gain on dealership divestitures, net Gain on divestitures, net Gain on divestitures, net Gain (Loss) on Disposition of Business Interest payments made excluding amounts capitalized Interest Paid, Excluding Capitalized Interest, Operating Activity Document Fiscal Year Focus Document Fiscal Year Focus Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Lender Name [Axis] Lender Name [Axis] OPERATING LEASE RIGHT-OF-USE ASSETS Operating Lease, Right-of-Use Asset Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Schedule of Available-for-sale Securities [Table] Schedule of Gain (Loss) on Securities [Table] Entity Interactive Data Current Entity Interactive Data Current Amortization of costs incurred to obtain a contract with a customer Contract with Customer, Asset, Amortization of costs to obtain a contract with a customer Contract with Customer, Asset, Amortization of costs to obtain a contract with a customer 2021 Real Estate Facility 2021 Real Estate Facility [Member] 2021 Real Estate Facility Deferred Revenue Location [Axis] Deferred Revenue Location [Axis] Deferred Revenue Location Carrying Value: Reported Value Measurement [Member] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Other selling, general and administrative expense Other Selling, General and Administrative Expense SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] 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] U.S. Treasuries US Treasury Securities [Member] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Current maturities of long-term debt Less—current portion, net of debt issuance costs Long-Term Debt and Lease Obligation, Current Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Luxury Brands Luxury Brands [Member] Luxury Brands [Member] Other liabilities Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Table] Fair Value, Recurring and Nonrecurring [Table] Selling, general, and administrative Selling, General and Administrative Expense Depreciation and amortization Depreciation, Depletion and Amortization OTHER LONG-TERM ASSETS Other Assets, Noncurrent Weighted brand mix (percent) Brand Mix Brand Mix Entity Central Index Key Entity Central Index Key PEO Name PEO Name TOTAL REVENUE Revenues Revenues Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Revolving credit facility Revolving Credit Facility [Member] Finance Lease, Liability Finance Lease, Liability Arrangement Duration Trading Arrangement Duration Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual Deferred revenue—current Contract with Customer, Liability, Current Number of collision repair centers (in collision repair centers) Number of Collision Repair Centers Number of Collision Repair Centers Segments [Axis] Segments [Axis] Audi Audi [Member] Audi Schedule of Derivative Instruments Fair Value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Total accounts receivable Accounts Receivable, before Allowance for Credit Loss, Current Schedule of Long Lived Assets Held-for-sale [Table] Long-Lived Asset, Held-for-Sale [Table] Contract assets, long-term Contract with Customer, Asset, after Allowance for Credit Loss, Noncurrent Repurchase and retirement of common stock (in shares) Repurchase and retirement of common stock (in shares) Stock Repurchased and Retired During Period, Shares Notional Principal at Maturity Derivative Liability, Notional Amount, at Maturity Derivative Liability, Notional Amount, at Maturity ASSETS Assets [Abstract] Credit Facility [Axis] Credit Facility [Axis] Results Recognized in Accumulated Other Comprehensive Income/(Loss) (Effective Portion) OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment, before Tax Underlying Security Market Price Change Underlying Security Market Price Change, Percent Statement of Financial Position Location, Balance [Axis] Statement of Financial Position Location, Balance [Axis] Debt Instrument [Axis] Debt Instrument [Axis] Business Combination [Line Items] Business Combination [Line Items] Credit Facility [Domain] Credit Facility [Domain] SHAREHOLDERS' EQUITY: Equity, Attributable to Parent [Abstract] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Operating lease liabilities Operating Lease Liability, Operating Activities Operating Lease Liability, Operating Activities Number of states (in states) Number of States in which Entity Operates Entity Address, Address Line One Entity Address, Address Line One New vehicles New Vehicles [Member] New Vehicles Share repurchases Treasury Stock, Value, Acquired, Cost Method Interest rate swap, net gain amount expected to be reclassified in the next twelve months Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Stated interest rate of debt instrument Stated interest rate of debt instrument Debt Instrument, Interest Rate, Stated Percentage Less—Allowance for credit losses Accounts Receivable, Allowance for Credit Loss, Current Investments [Domain] Investments [Domain] LONG-TERM LEASE LIABILITY Operating Lease, Liability, Noncurrent Dealerships Dealerships [Member] Dealerships Schedule of Components of Inventory [Table] Schedule of Components of Inventory [Table] Schedule of Components of Inventory [Table] Floor Plan Notes Payable [Line Items] Floor Plan Notes Payable [Line Items] Floor Plan Notes Payable [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Fair Value as of Grant Date Award Grant Date Fair Value Entity Registrant Name Entity Registrant Name Floor plan repayments—non-trade Repayments Of Floor Plan Payables Non Trade Repayments of floorplan notes payable to parties other than the manufacturer of the new vehicle and all floorplan notes payable related to pre-owned vehicles. Costs incurred to obtain a contract with a customer Contract with Customer, Costs to Obtain Contract Contract with Customer, Costs to Obtain Contract Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Municipal Municipal Bonds [Member] Held-for-sale Disposal Group, Held-for-Sale, Not Discontinued Operations [Member] Accounts payable and accrued liabilities Disposal Group, Including Discontinued Operation, Liabilities Other interest expense, net Other interest expense, net Interest Expense, Other Personnel costs Labor and Related Expense Total Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] Manufacturer receivables Manufacturer Receivables [Member] Manufacturer Receivables [Member] Schedule of Long-term Debt Schedule of Long-Term Debt Instruments [Table Text Block] Deferred Sales Commissions Deferred Sales Commissions [Member] Deferred Sales Commissions Document Quarterly Report Document Quarterly Report Less than 12 months, fair value Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months Parts and accessories Parts and accessories [Member] Parts and Accessories Long-term debt Long-Term Debt, Fair Value Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Schedule of Floor Plan Notes Payable Schedule of Debt [Table Text Block] Investment Type [Axis] Investment Type [Axis] Income tax benefit (expense) associated with available-for-sale debt securities Other Comprehensive Income (Loss), Available-for-Sale Securities, Tax, Portion Attributable to Parent Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Restatement Determination Date: Restatement Determination Date [Axis] Payments to acquire businesses, gross Payments to Acquire Businesses, Gross Non-PEO NEO Non-PEO NEO [Member] Amount of letters of credit outstanding Letters of Credit Outstanding, Amount Fair value of interest rate swaps Interest Rate Cash Flow Hedge Derivative at Fair Value, Net Schedule of Carrying Values and Fair Values of Liabilities Fair Value, Liabilities Measured on Recurring Basis [Table Text Block] Notional Principal at Inception Derivative Liability, Notional Amount Gross Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Name Trading Arrangement, Individual Name Assets: Disposal Group, Including Discontinued Operation, Assets [Abstract] Award Type [Domain] Award Type [Domain] Results Recognized in Accumulated Other Comprehensive Income/(Loss) (Effective Portion) Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax Equity Awards Adjustments Equity Awards Adjustments [Member] Advertising Advertising Expense Other adjustments, net Other Noncash Income (Expense) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Fair Value: Estimate of Fair Value Measurement [Member] Real estate facility Real Estate Facility [Member] Real Estate Facility MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Due in 1-5 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year One Through Five Name Awards Close in Time to MNPI Disclosures, Individual Name Used vehicle Used Vehicle [Member] Used Vehicle Type of Brand [Axis] Type of Brand [Axis] Type of Brand [Axis] Dealership Location Dealership Location [Member] Dealership Location Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Franchise Franchise [Member] REVENUE: Revenues [Abstract] New and used vehicle New and Used Vehicle [Member] New and used vehicle [Member] Due in 5-10 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Share-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Treasury stock, at cost; 22,147,927 and 22,109,690 shares, respectively Treasury Stock, Value Floor plan notes payable—trade, net Increase (Decrease) In Floor Plan Notes Payable Trade The net change during the reporting periods of floor plan notes payable with the manufacturer of new vehicles. Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax LONG-TERM DEBT Long-Term Debt and Lease Obligation Financial Instruments [Domain] Financial Instruments [Domain] Unrealized gain on changes in fair value of debt securities, net of reclassification adjustment and tax expense OCI, Debt Securities, Available-for-Sale, Gain (Loss), after Adjustment and Tax Increases related to revenue recognized, inclusive of adjustments to constraint, during the period Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress Segments [Domain] Segments [Domain] Schedule of Derivative Instruments Effect on Accumulated Other Comprehensive Income Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block] Statement of Income Location, Balance [Axis] Statement of Income Location, Balance [Axis] Land Rover Land Rover [Member] Land Rover New vehicle New Vehicle [Member] New vehicle [Member] Performance share units Performance Shares [Member] INVESTMENTS Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Chevrolet Franchise Chevrolet Franchise [Member] Chevrolet Franchise Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Liabilities: Disposal Group, Including Discontinued Operation, Liabilities [Abstract] Floor plan notes payable-trade Disposal Group, Including Discontinued Operation, Operating Leases, Current Maturities Disposal Group, Including Discontinued Operation, Operating Leases, Current Maturities Statement of Financial Position Location, Balance [Domain] Statement of Financial Position Location, Balance [Domain] Inventories, net Increase (Decrease) in Inventories Used vehicle floor plan facility Used Vehicle Floor Plan Facility [Member] Used Vehicle Floor Plan Facility [Member] Inventories, net Total inventories Inventory, Net Earnings per Share Earnings Per Share, Policy [Policy Text Block] COST OF SALES: Cost of Revenue [Abstract] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Company Selected Measure Name Company Selected Measure Name Rent and related expenses Rent And Related Expenses Rent And Related Expenses Fair Value Measurement [Domain] Fair Value Measurement [Domain] Total debt outstanding Long-Term Debt and Lease Obligation, Including Current Maturities Senior Notes Senior Notes [Member] Purchases of debt securities—available-for-sale Payments to Acquire Debt Securities, Available-for-Sale Preferred stock, $.01 par value; 10,000,000 shares authorized; none issued or outstanding Preferred Stock, Value, Issued Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Total liabilities assumed Business Combination, Recognized Liability Assumed, Liability All Executive Categories All Executive Categories [Member] Common stock, $.01 par value; 90,000,000 shares authorized; 40,099,276 and 41,338,419 shares issued, including shares held in treasury, respectively Common Stock, Value, Issued Short-term investments Short-Term Investments COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted COMMITMENTS AND CONTINGENCIES (Note 13) Commitments and Contingencies Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Derivative [Table] Derivative [Table] Intangible franchise rights Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived Business Combination [Axis] Business Combination [Axis] Entity Small Business Entity Small Business Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding FLOOR PLAN NOTES PAYABLE DEBT Long-Term Debt [Text Block] Document Transition Report Document Transition Report Due in 1-5 years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five Number of dealership locations (in dealership locations) Number Of Dealership Locations Number Of Dealership Locations Short-term investments Short-Term Investments [Member] Underlying Securities Award Underlying Securities Amount Debt securities, available-for-sale, realized gain Debt Securities, Available-for-Sale, Realized Gain Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Loaner Vehicle Notes Payable - Bank of America Loaner Vehicle Notes Payable - Bank of America [Member] Loaner Vehicle Notes Payable - Bank of America Due after 10 years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 10 Add—unamortized premium Debt Instrument, Unamortized Premium Diluted— Earnings Per Share, Diluted [Abstract] Proceeds from revolving credit facility Proceeds from Lines of Credit Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] 2023 Syndicated Revolving Credit Facility 2019 Bank of America Revolving Credit Facility [Member] 2019 Bank of America Revolving Credit Facility [Member] Volvo Franchise Volvo Franchise [Member] Volvo Franchise Goodwill Disposal Group, Including Discontinued Operation, Goodwill Dealerships acquired Business Combination, Dealerships Acquired Business Combination, Dealerships Acquired Inventory Disposal Group, Including Discontinued Operation, Inventory Mortgage and other asset-backed securities Mortgage And Other Assets Backed Securities [Member] Mortgage And Other Assets Backed Securities Document Type Document Type Level 3 Fair Value, Inputs, Level 3 [Member] Name Outstanding Recovery, Individual Name Loss Contingencies [Table] Loss Contingencies [Table] Product and Service [Axis] Product and Service [Axis] Number of instruments held Derivative, Number of Instruments Held Derivative Contract [Domain] Derivative Contract [Domain] Notes payable Notes Payable Debt securities, available-for-sale, realized loss Debt Securities, Available-for-Sale, Realized Loss All Individuals All Individuals [Member] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Name Forgone Recovery, Individual Name Total current assets Assets, Current Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Stock repurchase program, authorized amount Share Repurchase Program, Authorized, Amount Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Disposal Group Name [Axis] Disposal Group Name [Axis] Repurchases of common stock, associated with net share settlements of employee share-based awards Payment, Tax Withholding, Share-Based Payment Arrangement Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Schedule of Derivative Instruments Schedule of Derivative Instruments [Table Text Block] Schedule of Business Organization Schedule of Business Organization [Table] Schedule of Business Organization [Table] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] CURRENT LIABILITIES: Liabilities, Current [Abstract] Floor plan notes payable—non-trade, net Floor plan notes payable—non-trade, net Floor Plan Notes Payable Non Trade Amounts borrowed to finance the purchase of specific new and, to a lesser extent, used vehicle inventories with non-trade lenders (lenders that are not captive finance subsidiaries of the manufacturer). Other long-term assets and liabilities, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Level 1 Fair Value, Inputs, Level 1 [Member] Net income (in dollars per share) Earnings Per Share, Diluted Loaner vehicle amortization Cost, Depreciation and Amortization Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Title of 12(b) Security Title of 12(b) Security Due in 5-10 years Debt Securities, Available-for-Sale, Fair Value, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Interest Rate Swap, May 2021 Interest Rate Swap, May 2021 [Member] Interest Rate Swap, May 2021 Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Number of franchises (in franchises) Number of Franchises Number of Franchises Treasury stock (in shares) Treasury stock, beginning balance (in shares) Treasury stock, ending balance (in shares) Treasury Stock, Common, Shares Change in right-of-use assets Change in Operating Lease, Right of Use Asset Change in Operating Lease, Right of Use Asset EARNINGS PER SHARE: Earnings Per Share [Abstract] Consolidation Items [Domain] Consolidation Items [Domain] Floor plan notes payable offset account Floor Plan Notes Payable Non Trade, Offsets Floor Plan Notes Payable Non Trade, Offsets Total other expenses, net Nonoperating Income (Expense) Sale of vehicle parts and accessories Sale Of Parts and Services [Member] Sale Of Parts and Services Investments, Debt and Equity Securities [Abstract] Number of vehicle brands (in vehicle brands) Number of Vehicle Brands Number of Vehicle Brands GROSS PROFIT Gross Profit Retirement of common stock Stock Repurchased and Retired During Period, Value Capital expenditures—excluding real estate Payments to Acquire Property, Plant, and Equipment, Excluding Real Estate Payments to Acquire Property, Plant, and Equipment, Excluding Real Estate Contracts-in-transit, net Increase (Decrease) in Contract with Customer, Liability Nissan Franchise Nissan Franchise [Member] Nissan Franchise Gain (Loss) on Securities [Line Items] Gain (Loss) on Securities [Line Items] Franchise rights Disposal Group, Including Discontinued Operation, Intangible Assets Income taxes paid, net Income Taxes Paid, Net Shares repurchased (in shares) Treasury Stock, Shares, Acquired Award Timing Disclosures [Line Items] Chrysler Jeep Dodge Ram Franchise Chrysler Jeep Dodge Ram Franchise [Member] Chrysler Jeep Dodge Ram Franchise Schedule of Inventory Schedule of Inventory, Current [Table Text Block] Long-term debt, gross Long-Term Debt, Gross Measurement Frequency [Domain] Measurement Frequency [Domain] Current maturities of operating leases Asset, Held-for-Sale, Not Part of Disposal Group Business Organization [Line Items] Business Organization [Line Items] Business Organization [Line Items] Parts and service Parts And Service [Member] Parts And Service NET INCOME Net income Net Income (Loss) Attributable to Parent Intersegment Eliminations Intersegment Eliminations [Member] Schedule of Unrealized Loss on Investments Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value [Table Text Block] Expiration Date Trading Arrangement Expiration Date Toyota Franchise Toyota Franchise [Member] Toyota Franchise PROPERTY AND EQUIPMENT, net Property, Plant and Equipment, Net Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Purchases of treasury stock Payments for repurchase of common stock Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Long Lived Assets Held-for-sale [Line Items] Long-Lived Assets Held-for-Sale [Line Items] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Accounts receivable, net Increase (Decrease) in Accounts Receivable Beginning balance Ending balance Contract with Customer, Asset, after Allowance for Credit Loss Contracts-in-transit, net Contracts In Transit Contracts-in-transit represent receivables from third-party finance companies for the portion of new and used vehicle purchase price financed by customers through sources arranged by us. Entity Current Reporting Status Entity Current Reporting Status Receivables [Abstract] Receivables [Abstract] Derivative [Line Items] Derivative [Line Items] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Mid-line Import Brands Mid-line Import Brands [Member] Mid-line Import Brands [Member] INCOME FROM OPERATIONS INCOME FROM OPERATIONS Operating Income (Loss) Line of Credit Line of Credit [Member] Due in 1 year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Capital expenditures—real estate Payments to Acquire Real Estate Retained earnings Retained Earnings (Accumulated Deficit) Financial Instrument [Axis] Financial Instrument [Axis] Loaner vehicles transferred from other current assets to inventory Loaner Vehicles, Amount Transferred from Other Current Assets to Inventory Loaner vehicles transferred from other current assets to inventory on the condensed consolidated balance sheets Balance Sheet: Statement of Financial Position [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Executive Category: Executive Category [Axis] 12 months or longer, unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Current Fiscal Year End Date Current Fiscal Year End Date Collision centers acquired Business Combination, Collision Centers Acquired Business Combination, Collision Centers Acquired Less than 12 months, unrealized losses Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Impairment of Intangible Assets, Finite-Lived Impairment of Intangible Assets, Finite-Lived Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Reastated Credit Agreement Reastated Credit Agreement [Member] Reastated Credit Agreement [Member] Liabilities associated with assets held for sale Disposal Group, Including Discontinued Operation, Liabilities, Current Schedule of Accounts Receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Payables and Accruals [Abstract] Payables and Accruals [Abstract] Statement [Table] Statement [Table] Business Combination Business Combination [Table Text Block] Adjustments to reconcile net income to net cash provided by operating activities— Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] CASH FLOW FROM FINANCING ACTIVITIES: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Net assets acquired Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill Used vehicle wholesale Used vehicle wholesale [Member] Used vehicle wholesale [Member] Accounts receivable, net Accounts receivable, net Receivables, Net, Current Total unrealized losses Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Fiscal Year Maturity [Abstract] Deferred revenue Contract with Customer, Liability 4.50% Senior Notes due 2028 Four Point Five Zero Percent Senior Notes due 2028 [Member] Four Point Five Zero Percent Senior Notes due 2028 [Member] Antidilutive securities excluded from computation of earnings per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount WEIGHTED AVERAGE SHARES OUTSTANDING: Weighted Average Number of Shares Outstanding, Diluted [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities, Current Amendment Flag Amendment Flag Fair Value Debt Securities, Available-for-Sale, Fair Value, Fiscal Year Maturity [Abstract] Schedule of Fair Value, Assets Measured on Recurring and Nonrecurring Basis Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Table Text Block] Used vehicles Used Vehicles [Member] Used Vehicles Termination Date Trading Arrangement Termination Date Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Deferred revenue Increase (Decrease) in Contract with Customer, Asset Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Disclosure of Long-Lived Assets Held-for-Sale Disclosure of Long-Lived Assets Held-for-Sale [Table Text Block] Receivable [Domain] Receivable [Domain] Business Combination, Acquiree's Revenue since Acquisition Date, Actual Business Combination, Acquiree's Revenue since Acquisition Date, Actual Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Stock repurchase program, remaining authorized repurchase amount Share Repurchase Program, Remaining Authorized, Amount SUPPLEMENTAL CASH FLOW INFORMATION Cash Flow, Supplemental Disclosures [Text Block] Floor plan notes payable—trade, net Floor plan notes payable—trade, net Floor Plan Notes Payable Trade Amounts borrowed to finance the purchase of specific new vehicle inventories with the corresponding manufacturers' captive finance subsidiaries ("trade lenders"). Disposal Group Classification [Domain] Disposal Group Classification [Domain] Transferred to receivables from contract assets recognized at the beginning of the period Contract with Customer, Asset, Reclassified to Receivable Number of businesses acquired Business Combination, Number of Businesses Acquired Segment Reporting [Abstract] TOTAL COST OF SALES Cost of sales Cost of Revenue Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Number of dealerships under investigation Loss Contingency, Number Of Dealerships Under Investigation Loss Contingency, Number Of Dealerships Under Investigation Debt Disclosure [Abstract] Debt Disclosure [Abstract] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Entity Tax Identification Number Entity Tax Identification Number Vehicle receivables Vehicle Receivables [Member] Vehicle Receivables [Member] Interest payments made including amounts capitalized Interest Paid, Including Capitalized Interest, Operating and Investing Activities Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued (in shares) Common Stock, Shares, Issued Use of Estimates Use of Estimates, Policy [Policy Text Block] Number of dealerships that violated FTC Act Loss Contingency, Dealerships That Violated FTC Act, Number Loss Contingency, Dealerships That Violated FTC Act, Number Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Loss Contingencies [Line Items] Loss Contingencies [Line Items] Insider Trading Arrangements [Line Items] Security Exchange Name Security Exchange Name Vehicle repair and maintenance services Vehicle Repair and Maintenance Services [Member] Vehicle repair and maintenance services [Member] Total by maturity Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] OPERATING EXPENSES: Operating Expenses [Abstract] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Statement [Line Items] Statement [Line Items] Change in Contract with Customer, Asset [Roll Forward] Change in Contract with Customer, Asset [Roll Forward] Change in Contract with Customer, Asset [Roll Forward] Consolidation Items [Axis] Consolidation Items [Axis] Deferred Revenue Location [Domain] Deferred Revenue Location [Domain] Deferred Revenue Location [Domain] Deferral of SG&A expense (related to capitalized contract costs offset by amortization) Deferral Of Selling, General And Administrative Expenses Deferral Of Selling, General And Administrative Expenses Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Common Stock Common Stock [Member] Fair Value Debt Securities, Available-for-Sale Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate Corporate Debt Securities [Member] Porsche Porsche [Member] Porsche Net decrease in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation