Total ending managed receivables as percentage by major credit grade Total ending managed receivables as percentage by major credit grade Total ending managed receivables as percentage by major credit grade. Thirty One To Sixty Days Past Due [Member] Thirty One To Sixty Days Past Due [Member] Thirty One To Sixty Days Past Due [Member] Maximum Maximum [Member] Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff Statistical Measurement [Domain] Statistical Measurement [Domain] NET SALES AND OPERATING REVENUES Net Sales And Operating Revenues [Member] Net sales and operating revenues member Title of 12(b) Security Title of 12(b) Security Subsequent Event [Member] Subsequent Event [Member] Document Fiscal Year Focus Document Fiscal Year Focus Total other expense, percent Total Other Nonoperating (Expense) Income Percent [Member] Total Other Nonoperating (Expense) Income Percent [Member] Federal Income Tax Note Investments, Owned, Federal Income Tax Note [Line Items] Financial Instrument [Axis] Financial Instrument [Axis] Market Stock Units Converted To Common Stock Conversion Ratio Number Of Final Trading Days In Vesting Period Market Stock Units Converted To Common Stock Conversion Ratio Number Of Final Trading Days In Vesting Period Market Stock Units Converted To Common Stock Conversion Ratio Number Of Final Trading Days In Vesting Period Interest expense, percent Interest Expense [Member] (Deprecated 2026) Receivables, Long-term Contracts or Programs Receivables, Long-Term Contracts or Programs Common stock, $0.50 par value; 350,000,000 shares authorized; 141,909,099 and 141,799,070 shares issued and outstanding as of May 31, 2026 and February 28, 2026, respectively Common Stock, Value, Issued Interest expense Interest Expense, Operating and Nonoperating PSU Performance Adjustment Factor PSU Performance Adjustment Factor PSU Performance Adjustment Factor Percent of total assets Item As Percentage Of Total Assets Item as percentage of total assets Credit Facility Line of Credit [Member] Credit Grade A Credit Grade A [Member] Credit grade A member Auto Loan Receivables Financing Receivables [Text Block] Net unrecognized beneficial interests gains (losses) Net unrecognized beneficial interests gains (losses) [Member] Net unrecognized beneficial interests gains (losses) Amendment Flag Amendment Flag CURRENT LIABILITIES: Liabilities, Current [Abstract] Average Cost Per Share Shares Acquired, Average Cost Per Share Composition Of Share-Based Compensation Expense - By Grant Type Schedule Of Share Based Compensation Expense By Grant Type [Table Text Block] Schedule Of Share Based Compensation Expense By Grant Type [Table Text Block] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Finance Lease, Principal Payments Finance Lease, Principal Payments CarMax Auto Finance Income [Abstract] CarMax Auto Finance Income [Abstract] Auto Finance Income [Abstract] Auto loans sold in exchange for beneficial interests Auto loans sold in exchange for beneficial interests Auto loans sold in exchange for beneficial interests Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, to be Paid, after Year Five Asset-Backed Securities Asset-Backed Securities [Member] Other Depreciation and Amortization Other Depreciation and Amortization Auto loans held for investment Auto loans held for investment [Member] Auto loans held for investment Total direct expenses, percent Total Direct Expenses [Member] Total Direct Expenses [Member] Other Comprehensive Income (Loss), Net of Tax [Abstract] Other Comprehensive Income (Loss), Net of Tax [Abstract] Leases [Abstract] Leases [Abstract] Item as percent of total ending managed receivables Item As Percent Of Total Ending Managed Receivables (Increase) Item as percent of total ending managed receivables Overcollateralization Excess Collateral [Member] Receivables restricted as excess collateral for receivable funding arrangements. PSU First-year Period PSU First-year Period [Member] PSU First-year Period WEIGHTED AVERAGE COMMON SHARES: Weighted Average Common Shares Abstract Weighted Average Common Shares 2 [Abstract] Entity Address, State or Province Entity Address, State or Province Auto loans held for investment, net Increase (Decrease) in Finance Receivables Auto Finance Income [Line Items] Auto Finance Income [Line Items] Auto Finance Income [Line Items] Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Share-based Payment Arrangement, Noncash Expense [Abstract] Share-Based Payment Arrangement, Noncash Expense [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Derivative, Notional Amount Derivative, Notional Amount Basic, shares Weighted average common shares outstanding, shares Weighted Average Number of Shares Outstanding, Basic Selling, general and administrative expenses Selling, general and administrative expense [Member] Selling, general and administrative expense SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] SEC Schedule, 12-09, Valuation Allowances and Reserves Type [Axis] Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Information Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Information [Table Text Block] Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Information Stock Settled Restricted Stock Units [Member] Stock Settled Restricted Stock Units [Member] Stock-Settled Restricted Stock Units [Member Reportable segments Number of Reportable Segments TOTAL CURRENT LIABILITIES  Liabilities, Current Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, to be Paid, Year Four Financing Receivable, By Major Credit Grade [Line Items] Financing Receivable, Credit Quality Indicator [Line Items] Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Activity Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Activity [Table Text Block] Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Activity Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Three Years Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Three Years Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Three Years Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Goodwill impairment Goodwill impairment [Member] Goodwill impairment Additional reclassification from AOCL to CAF income within the next 12 months Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Entity Address, City or Town Entity Address, City or Town Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Cancellation Reserves [Abstract] Cancellation Reserves [Abstract] Contract Cancellation Reserves [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Equity Method Investments, Fair Value Disclosure Equity Method Investments, Fair Value Disclosure Stock and Stock-Based Incentive Plans Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Financing Receivable, Recorded Investment, Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Receivables [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Components Of CarMax Auto Finance Income Schedule Of Components Of Net Income Loss From Financing [Table Text Block] Schedule Of Components Of Net Income Loss From Financing [Table Text Block] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Class of Stock [Axis] Class of Stock [Axis] Provision for cancellation reserves Provision for contract cancellation reserves Provision for contract cancellation reserves Level 2 Fair Value, Inputs, Level 2 [Member] Receivable Type [Domain] Receivable [Domain] Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Other comprehensive income (loss), net of taxes Other Comprehensive Income (Loss), Net of Tax Other Comprehensive Income (Loss), Net of Tax Current portion of long-term debt Long-Term Debt, Current Maturities Subsequent Event Type [Axis] Subsequent Event Type [Axis] Net change in cash flow hedge unrecognized gains, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Share-Based Payment Arrangement, Amount Capitalized Share-Based Payment Arrangement, Amount Capitalized Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Percent of total liabilities Item As Percentage Of Total Liabilities Item as percentage of total liabilities PSU Performance Adjustment Factor PSU Conversion Threshold PSU Conversion Threshold Financing Receivable, Allowance for Credit Loss, Writeoff Financing Receivable, Allowance for Credit Loss, Writeoff Financing Receivable, Allowance for Credit Loss, Writeoff Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] (Decrease) increase in accrued capital expenditures Capital Expenditures Incurred but Not yet Paid Fiscal 2024 Grant Fiscal 2024 Grant [Member] Fiscal 2024 Grant Tax (expense) benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax Total interest margin after provision for loan losses, percent Total Interest Margin After Provision For Loan Losses [Member] Total Interest Margin After Provision For Loan Losses [Member] Use of Estimates Use of Estimates, Policy [Policy Text Block] Total other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Other direct expenses, percent Other Direct Expenses [Member] Other Direct Expenses [Member] Long-term Debt Outstanding Balance Long-Term Debt SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] SEC Schedule, 12-09, Valuation Allowances and Reserves [Domain] Document Period End Date Document Period End Date Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Next Fiscal Year Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Next Fiscal Year Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Next Fiscal Year Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Unrecognized tax benefits, gross Unrecognized Tax Benefits Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, to be Paid, Year Two Security Exchange Name Security Exchange Name Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Two Years Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Two Years Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Expected Cash Payouts Upon Vesting In Two Years Proceeds from Sales of Business, Affiliate and Productive Assets Proceeds from Sales of Business, Affiliate and Productive Assets Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Financing Receivable, before Allowance for Credit Loss Financing Receivable, before Allowance for Credit Loss Cash Flow, Supplemental Disclosures [Text Block] Cash Flow, Supplemental Disclosures [Text Block] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Finance Lease, Weighted Average Remaining Lease Term Finance Lease, Weighted Average Remaining Lease Term Total liabilities at fair value Liabilities, Fair Value Disclosure Accumulated other comprehensive loss Beginning balance Ending balance Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Current portion of operating lease liabilities Operating Lease, Liability, Current Finance Lease, Right-of-Use Asset Finance Lease, Right-of-Use Asset, after Accumulated Amortization Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Net Earnings Per Share Earnings Per Share [Text Block] Increase (Decrease) in Receivable for Investment Sold Increase (Decrease) in Receivable for Investment Sold NET EARNINGS PER SHARE: Earnings Per Share [Abstract] Earnings Per Share [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Mutual fund investments Debt Securities, Trading, and Equity Securities, FV-NI TOTAL LIABILITIES  Liabilities Trading Symbol Trading Symbol Capital expenditures Payments to Acquire Property, Plant, and Equipment Other Lease Disclosures [Table Text Block] Other Lease Disclosures [Table Text Block] Other required lease disclosures, including lease term, discount rate and cash flow information. Accrued income taxes Accrued Income Taxes, Current Financing obligation Financing Obligation [Member] Financing Obligation Member Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Issuances of non-recourse notes payable Proceeds From Issuance Of Non-Recourse Debt The cash inflow from the issuance of non-recourse debt through the securitization of auto loan receivables. Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Interest expense Financing Interest Expense Finance Lease Accumulated Depreciation Finance Lease Accumulated Depreciation Accumulated depreciation of finance leases Credit Facility [Domain] Credit Facility [Domain] Depreciation, Depletion and Amortization, Nonproduction Depreciation, Depletion and Amortization, Nonproduction OPERATING ACTIVITIES: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Diluted, shares Weighted average common shares and dilutive potential common shares, shares Weighted Average Number of Shares Outstanding, Diluted Fiscal 2022 grants Fiscal 2022 Grant [Member] Fiscal 2022 Grant Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Warehouse Facility Two Warehouse Facility Two [Member] The second warehouse facility used to fund auto loan receivables originated by the entity until the receivables are funded through a term securitization or alternative funding arrangement. Entity Emerging Growth Company Entity Emerging Growth Company Finance Lease, Liability, Payments, Due Year Two Finance Lease, Liability, to be Paid, Year Two Financing Receivable, Originated in Current Fiscal Year Financing Receivable, Year One, Originated, Current Fiscal Year Finance Lease, Liability, Payments, Due Year Four Finance Lease, Liability, to be Paid, Year Four Lease renewal term Lease renewal term Lease renewal term Derivative Instruments And Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Entities [Table] Entities [Table] Lessee, Operating Lease, Liability, Undiscounted Excess Amount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Term Securitizations Debt [Member] Term Securitizations Debt [Member] Term Securitizations Debt Member GROSS PROFIT  Gross Profit Allowance For Loan Losses Financing Receivable, Noncurrent, Allowance for Credit Loss [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Other Other Receivables Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Finance Lease, Liability, Undiscounted Excess Amount Finance Lease, Liability, Undiscounted Excess Amount Share-Based Payment Arrangement, Exercise of Option, Tax Benefit Share-Based Payment Arrangement, Exercise of Option, Tax Benefit Operating Lease, Payments Operating Lease, Payments Payments on long-term debt Payments on Revolving Line of Credit and Long-Term Debt The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. Auto Finance Income [Table] Auto Finance Income [Table] Auto Finance Income [Table] Changes In And Reclassifications Out Of Accumulated Other Comprehensive Loss Comprehensive Income (Loss) [Table Text Block] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, before Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, before Tax, Portion Attributable to Parent APIC, Share-based Payment Arrangement, Increase for Cost Recognition APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Level 1 Fair Value, Inputs, Level 1 [Member] Total other expense Other Nonoperating Expense Financing Receivable, Originated Two Years before Latest Fiscal Year Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year Fiscal 2025 Grant Fiscal 2025 Grant [Member] Fiscal 2025 Grant Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Liability, to be Paid Proceeds from Sale, Loan, Held-for-Sale Proceeds from Sale, Loan, Held-for-Sale Wholesale vehicle sales Wholesale Vehicles [Member] Wholesale Vehicles [Member] Dilutive potential common shares, shares Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Information Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Information [Table Text Block] Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Information Stock Repurchased and Retired During Period, Value Stock Repurchased and Retired During Period, Value Deferred Stock Units [Member] Stock-settled deferred stock units (DSUs) Deferred Stock Units [Member] Deferred Stock Units [Member] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Vesting [Domain] Vesting [Domain] Plan Name [Domain] Plan Name [Domain] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Schedule of Share Per Unit Activity Schedule of Share Per Unit Activity [Text Block] Schedule of Share Per Unit Activity RECONCILIATION OF CASH, CASH EQUIVALENTS AND RESTRICTED CASH TO THE CONSOLIDATED BALANCE SHEETS: Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation [Abstract] Operating lease assets Operating Lease, Right-of-Use Asset Financing Receivable, before Allowance for Credit Loss, Current Financing Receivable, before Allowance for Credit Loss, Current Basic And Dilutive Net Earnings Per Share Reconciliations Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Debt Disclosure [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Increase in financing obligations Financing obligations incurred The increase/decrease during the period in financing obligations due to entering into or modifying existing lease-related financing obligations. Minimum Minimum [Member] Increase in cash, cash equivalents, and restricted cash Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation Hedging Relationship [Axis] Hedging Relationship [Axis] Liability associated with guarantee Standard Product Warranty Accrual Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Income Statement Location [Axis] Location, Statement of Income, Balance [Axis] Money market securities Cash and Cash Equivalents, Fair Value Disclosure TOTAL SHAREHOLDERS’ EQUITY  BALANCE BALANCE Equity, Including Portion Attributable to Noncontrolling Interest Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted-Average Remaining Contractual Term Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted-Average Remaining Contractual Term Other Comprehensive Income (Loss), Available-for-Sale Securities, Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Available-for-Sale Securities, Tax, Portion Attributable to Parent Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Derivative [Table] Derivative [Table] Finance Lease, Cost Finance Lease, Cost Total Finance Lease Cost, including interest on lease liabilities and depreciation of lease assets. Financing Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] Common Stock, Shares Authorized Common Stock, Shares Authorized Valuation Allowance [Table] Deferred Tax Asset, Valuation Allowance [Table] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] INVESTING ACTIVITIES: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Stock Repurchase Program, Authorized Amount Share Repurchase Program, Authorized, Amount Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Retained Interest, Fair Value Disclosure Beneficial interests in non-consolidated securitizations Beneficial interests in non-consolidated securitizations Document Quarterly Report Document Quarterly Report Item as percent of total average managed receivables Item As Percent Of Total Average Managed Receivables, Principal Only Item as percent of total average managed receivables, principal only Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Interest Rate Swaps Interest Rate Swap [Member] Lender Name [Axis] Lender Name [Axis] Earnings before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Debt Debt Disclosure [Text Block] Stock units converted to common stock for each unit granted Stock units converted to common stock for each unit granted Stock units converted to common stock for each unit granted Auto loans held for investment, net of allowance for loan losses of $474,986 and $453,027 as of May 31, 2026 and February 28, 2026, respectively Financing Receivable, after Allowance for Credit Loss Financing Receivable, after Allowance for Credit Loss Income tax provision Income Tax Provision [Member] Income tax provision Warehouse Facilities [Member] Warehouse Facilities [Member] A revolving securitization program comprised of one or more warehouse facilities that are used to fund auto loan receivables originated by the entity's finance company until the receivables are funded through a term securitization or alternative funding arrangement. 4.17% senior notes due 2026 [Member] 4.17% senior notes due 2026 [Member] 4.17% senior notes due 2026 [Member] Equity Component [Domain] Equity Component [Domain] Loans Receivable, Fair Value Disclosure Loans Receivable, Fair Value Disclosure Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance Finance Lease, Weighted Average Discount Rate, Percent Finance Lease, Weighted Average Discount Rate, Percent Equity issuances Proceeds from Issuance or Sale of Equity Asset-backed term funding Term Securitizations [Member] Term securitizations are used to provide long term funding for auto loan receivables initially securitized through the warehouse facilities. Other income Nonoperating Income (Expense) Other Other [Domain] "Other" other revenues [Domain] Interest expense Interest expense as a percent of sales [Member] Interest expense as a percent of sales Percentage of Sales Percentage of Sales Abstract Percentage of Sales [Abstract] ASSETS Assets [Abstract] Cancellation Reserves Contract Cancellation Reserve [Text Block] Contract Cancellation Reserve [Text Block] CARMAX AUTO FINANCE INCOME  CarMax Auto Finance income Net Income (Loss) From Financing Income (loss) generated from the entity's financing of used and new vehicle retail sales, excluding the allocation of indirect costs or income. Auto Loans Receivable By Major Credit Grade Financing Receivable Credit Quality Indicators [Table Text Block] Current portion of non-recourse notes payable Non Recourse Debt, Current Current portion of the amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property. Operating Lease, Liability Operating Lease, Liability Finance Lease, Liability Finance Lease, Liability Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Initial lease terms, in years Initial Lease Terms Initial Lease Terms. Performance Shares [Member] Stock-settled performance stock units (PSUs) Performance Shares [Member] Sales and returns of investments Proceeds from Sale and Maturity of Other Investments Deferred income tax (benefit) provision Deferred Income Tax Expense (Benefit) Selling, general and administrative expenses Selling, General and Administrative Expense Supplemental Balance Sheet Disclosures [Text Block] Supplemental Balance Sheet Disclosures [Text Block] Decrease in Unrecognized Tax Benefits is Reasonably Possible Decrease in Unrecognized Tax Benefits is Reasonably Possible Servicing income Auto loan servicing income Auto loan servicing income Net Unrecognized Hedge Gains (Losses) Unrecognized Hedge Losses [Member] Unrecognized Hedge Losses [Member] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Contingent Liabilities Commitments and Contingencies Disclosure [Text Block] Anti-dilutive securities not included in calculation of diluted net earnings per share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Financial Asset, Period Past Due [Domain] Financial Asset, Aging [Domain] Short-term debt Short-Term Bank Loans and Notes Payable Total other sales and revenues Other [Member] Other, including EPP, Third-party and service. Entity Central Index Key Entity Central Index Key Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Total interest margin after provision for loan losses Interest Income (Expense), after Provision for Loan Loss Fiscal 2023 grants - Year 1 [Member] Fiscal 2023 grants - Year 1 [Member] Fiscal 2023 grants - Year 1 Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Table] Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Table] Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Table] Total direct expenses Direct Operating Costs Extended protection plan revenues Extended protection plan [Domain] Extended protection plan (EPP) [Domain] Other comprehensive income before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Income Statement [Abstract] Income Statement [Abstract] Document Transition Report Document Transition Report Federal Income Tax Note [Table] Federal Income Tax Note [Table] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Designated As Hedging Instrument Designated as Hedging Instrument [Member] Deferred Income Tax Assets, Net Deferred Income Tax Assets, Net Finance Lease, Liability, Noncurrent Finance Lease, Liability, Noncurrent Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] City Area Code City Area Code Variable Rate [Domain] Variable Rate [Domain] Business Combination, Consideration Transferred, Equity Interest, Type [Axis] Business Combination, Consideration Transferred, Equity Interest, Type [Axis] Tier 1 Tier 1 managed receivables [Member] Tier 1 managed receivables Finance Lease, Liability, Payment, Due Finance Lease, Liability, to be Paid Restricted Stock [Member] Restricted Stock [Member] AOCI Attributable to Parent [Member] AOCI Attributable to Parent [Member] Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expected Cash Payouts Upon Vesting Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expected Cash Payouts Upon Vesting Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Expected Cash Payouts Upon Vesting Debt Instrument, Fair Value Disclosure Debt Instrument, Fair Value Disclosure Balance as of beginning of period Balance as of end of period SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Activity Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Information [Table Text Block] Share-Based Payment Arrangement, Stock-Settled Restricted Stock Units, Information Statement [Line Items] Statement [Line Items] TOTAL ASSETS  Assets Entity [Domain] Entity [Domain] Net change in retirement benefit plan unrecognized actuarial losses, net of tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax Financing Receivable, by Credit Quality Indicator [Domain] Internal Credit Assessment [Domain] Cost of revenue Cost of sales as a percent of revenue [Member] Cost of sales as a percent of revenue Financing Receivable, Credit Quality Indicator [Table] Financing Receivable, Credit Quality Indicator [Table] Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Net change in retirement benefit plan unrecognized actuarial losses Amortization reclassifications recognized in net pension expense, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Composition of Share-Based Compensation Expense Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Stock-settled stock units and awards Stock Settled Stock Units And Awards [Member] Stock-Settlled Market and Performance Units and Restricted Stock Awards Stock and Stock-Based Incentive Plans Share-Based Payment Arrangement [Text Block] Other assets Increase (Decrease) in Other Operating Assets Background Nature of Operations [Text Block] Debt, Long-Term and Short-Term, Combined Amount Debt, Long-Term and Short-Term, Combined Amount Share Repurchase Program Share Repurchase Program [Member] Share Repurchase Program [Member] Other (income) expense as a percent of sales Other (income) expense as a percent of sales [Member] Other (income) expense as a percent of sales Share-based compensation expense, before income taxes Share-Based Payment Arrangement, Expense Stock Repurchased and Retired During Period, Shares Stock Repurchased and Retired During Period, Shares Other liabilities Other Liabilities, Noncurrent Warehouse Facility One Warehouse Facility One [Member] The first warehouse facility used to fund auto loan receivables originated by the entity until the receivables are funded through a term securitization or alternative funding arrangement. Goodwill Goodwill Cancellation reserves, current portion Cancellation reserves, current portion Total of current allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses. Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Finance Lease, Liability, Payments, Due after Year Five Finance Lease, Liability, to be Paid, after Year Five Non-Prime Auto Loans Receivable Non-Prime Auto Loans Receivable [Member] Non-Prime Auto Loans Receivable Net Unrecognized Actuarial Losses Unrecognized Actuarial Losses [Member] Unrecognized Actuarial Losses [Member] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Financing Receivable, Originated Four Years before Latest Fiscal Year Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff Retained Earnings [Member] Retained Earnings [Member] Operating lease liabilities, excluding current portion Operating Lease, Liability, Noncurrent Revolving Credit Facility [Member] Revolving Credit Facility [Member] Restatement [Domain] Revision of Prior Period [Domain] Long-term debt, excluding current portion Other Long-Term Debt, Noncurrent Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Financing Receivable, Originated Three Years before Latest Fiscal Year Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year Provision for future cancellations SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding BALANCE, SHARES BALANCE, SHARES Common Stock, Shares, Outstanding Cash paid for debt issuance costs Payments of Debt Issuance Costs PSU Third-year Period PSU Third-year Period [Member] PSU Third-year Period Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Diluted (in dollars per share) Diluted net earnings per share (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Past due receivables as a percentage of total auto loans held for investment Past due receivables as a percentage of total ending managed receivables Past due receivables as a percentage of total ending managed receivables Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Cash Flow Hedging Cash Flow Hedging [Member] Item As Percent Of Total Ending Managed Receivables, Period Increase (Decrease) Item As Percent Of Total Ending Managed Receivables, Period Increase (Decrease) Item As Percent Of Total Ending Managed Receivables, Period Increase (Decrease) Schedule Of Future Minimum Lease Obligations [Table Text Block] Schedule Of Future Minimum Lease Obligations [Table Text Block] Schedule Of Future Minimum Lease Obligations [Table Text Block] Financing Receivable, Originated Five or More Years before Latest Fiscal Year Financing Receivable, Originated, More than Five Years before Current Fiscal Year Term Loan [Member] Term Loan [Member] Term Loan [Member] Used vehicle sales Used Vehicles [Member] Used Vehicles [Member] Adjustments to reconcile net earnings to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Share-based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Revenue from Contract with Customer, Excluding Assessed Tax Revenue from Contract with Customer, Excluding Assessed Tax FINANCING ACTIVITIES: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Property and equipment, net of accumulated depreciation of $2,285,968 and $2,217,485 as of May 31, 2026 and February 28, 2026, respectively Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization CARMAX AUTO FINANCE INCOME  Net Income Loss From Financing [Member] Income (loss) generated from the entity's financing of used and new vehicle retail sales, excluding the allocation of indirect costs or income. Unused capacity Line of Credit Facility, Remaining Borrowing Capacity Financial Instruments [Domain] Financial Instruments [Domain] Financing Receivable, Allowance for Credit Loss Financing Receivable, Allowance for Credit Loss Non-recourse notes payable, excluding current portion Non-Recourse Debt Non-Current Non-current portion of the amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property. Derivative Asset Derivative Asset Stock Issued During Period, Value, Stock Options Exercised Stock Issued During Period, Value, Stock Options Exercised Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Financing Receivable, Held-for-Sale, Not Part of Disposal Group, Reconciliation to Cash Flow, Period Increase (Decrease) Financing Receivable, Held-for-Sale, Not Part of Disposal Group, Reconciliation to Cash Flow, Period Increase (Decrease) Financing Obligations Financing Obligations Represents obligations under sale-leaseback transactions that did not qualify for sale accounting Credit Grade B Credit Grade B [Member] Credit grade B member Schedule of the fair value of auto loans held for sale Schedule of Carrying Values and Estimated Fair Values of Auto Loans Held for Sale [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Auto Loans Held for Sale Inventory Increase (Decrease) in Inventories Operating Lease, Weighted Average Discount Rate, Percent Operating Lease, Weighted Average Discount Rate, Percent Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Provision for Loan, Lease, and Other Losses Provision for loan losses Provision for Loan, Lease, and Other Losses Lease, Cost [Table Text Block] Lease, Cost [Table Text Block] Other current assets Other Assets, Current Long-Term Debt, Weighted Average Interest Rate, at Point in Time Long-Term Debt, Weighted Average Interest Rate, at Point in Time Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Derivative, Gain (Loss) on Derivative, Net Derivative, Gain (Loss) on Derivative, Net Schedule Of Items Measured At Fair Value On A Recurring Basis Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Tax benefit Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax Fair Value Assumption, Date of Securitization or Asset-Backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Discount Rate Fair Value Assumption, Date of Securitization or Asset-Backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities, Discount Rate Current Fiscal Year End Date Current Fiscal Year End Date Finance Lease, Liability, Payments, Remainder of Fiscal Year Finance Lease, Liability, to be Paid, Remainder of Fiscal Year 4.27% senior notes due 2028 [Member] 4.27% senior notes due 2028 [Member] 4.27% senior notes due 2028 [Member] Derivative [Line Items] Derivative [Line Items] CarMax Auto Finance income, percent CarMax Auto Finance Income [Member] CarMax Auto Finance Income Other managed receivables Other Receivables [Member] The amount of the recorded investment in auto loan receivables that have not been funded through warehouse facilities or term securitizations. Interest income on beneficial interests in non-consolidated securitizations Interest income on beneficial interests in non-consolidated securitizations Interest income on beneficial interests in non-consolidated securitizations Entity File Number Entity File Number Equipment Lease Term Equipment Lease Term Equipment Lease Term Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture (Decrease) increase in short-term debt, net Proceeds from (Repayments of) Short-Term Debt lessee, minimum lease payments for leases not yet commenced lessee, minimum lease payments for leases not yet commenced Lessee, minimum lease payments for leases not yet commenced Sixty One To Ninety Days Past Due [Member] Sixty One To Ninety Days Past Due [Member] Sixty One To Ninety Days Past Due [Member] Reclassifications to CarMax Auto Finance income Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax Share-based Payment Arrangement, Option, Activity [Table Text Block] Share-Based Payment Arrangement, Option, Activity [Table Text Block] Senior Notes Senior Notes Common Stock, Shares, Issued Common Stock, Shares, Issued Total average managed receivables Total average managed receivables Total average managed receivables Entity Information [Line Items] Entity Information [Line Items] Non-recourse Notes Payable Non-recourse Notes Payable Non-recourse Notes Payable Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate Long-Term Debt, Percentage Bearing Variable Interest, Percentage Rate Accumulated Other Comprehensive Loss Comprehensive Income (Loss) Note [Text Block] Other direct expenses Other Cost and Expense, Operating Equity Components [Axis] Equity Components [Axis] Depreciation and Amortization, Nonproduction Other Depreciation and Amortization Depreciation and Amortization [Member] Depreciation and Amortization Accounts receivable, net Increase (Decrease) in Accounts Receivable Product and Service [Domain] Product and Service [Domain] Total interest margin, percent Interest Income Expense Net [Member] Interest Income Expense Net [Member] Advertising & subscription revenues [Domain] Advertising & subscription revenues [Domain] Advertising & subscription revenues Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Finance Lease, Liability, Current Finance Lease, Liability, Current Variable Rate [Axis] Variable Rate [Axis] Entity Small Business Entity Small Business Real Estate Lease Term Real Estate Lease Term Real Estate Lease Term TOTAL COMPREHENSIVE INCOME Comprehensive Income (Loss), Net of Tax, Attributable to Parent Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, to be Paid, Year Three Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio Quotient Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio Quotient Share-based Compensation Arrangement by Share-based Payment Award, Conversion Ratio Quotient Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Business Description and Accounting Policies [Text Block] Business Description and Accounting Policies [Text Block] Total interest margin Interest Income (Expense), Operating Payments on non-recourse notes payable Payments On Non-Recourse Debt The cash outflow from payments on non-recourse debt from securitizations. Interest and fee income, percent Interest And Fee Income [Member] Interest And Fee Income [Member] Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period Other assets Other Assets, Noncurrent Item as a percent of net sales and operating revenues Item as a percent of net sales and operating revenues Item as a percent of net sales and operating revenues Finance Lease, Liability, Payments, Due Year Three Finance Lease, Liability, to be Paid, Year Three Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Document Type Document Type Payments to Acquire Businesses, Net of Cash Acquired Payments to Acquire Businesses, Net of Cash Acquired 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] Prime Auto Loans Receivable Prime Auto Loans Receivable [Member] Prime Auto Loans Receivable Accrued expenses and other current liabilities Accrued Liabilities, Current Proceeds from issuances of long-term debt Proceeds from Revolving Line of Credit and Long-Term Debt The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from revolving line of credit and long-term debt. Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value Available for repurchase, as of end of period Share Repurchase Program, Remaining Authorized, Amount Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Net (increase) decrease in: Increase (Decrease) in Operating Assets [Abstract] Deferred tax Accumulated Other Comprehensive Income Loss Deferred Taxes The balance of deferred taxes on items remaining in accumulated other comprehensive income loss Tax expense Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax Allowance For Loan Losses, percent SEC Schedule, 12-09, Allowance, Loan and Lease Loss [Member] Commitments and contingent liabilities Commitments and Contingencies NET SALES AND OPERATING REVENUES Revenues Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Reclassification out of Accumulated Other Comprehensive Income [Axis] Reclassification out of Accumulated Other Comprehensive Income [Axis] New Accounting Pronouncements or Change in Accounting Principle [Table] Accounting Standards Update and Change in Accounting Principle [Table] Accounts payable, accrued expenses and other current liabilities and accrued income taxes Increase (Decrease) in Accounts Payable and Accrued Liabilities Finance Lease, Right-of-Use Asset, Amortization Finance Lease, Right-of-Use Asset, Amortization Receivable Type [Axis] Receivable Type [Axis] Net decrease in: Increase (Decrease) in Operating Liabilities [Abstract] GROSS PROFIT  Gross Profit [Member] Gross profit member Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period LIABILITIES AND SHAREHOLDERS’ EQUITY Liabilities and Equity [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted-Average Remaining Contractual Term Payments on finance lease obligations Repayments Of Long Term Finance And Capital Lease Obligations The cash outflow for obligations for sale-leasebacks being accounted for using the finance method or leases meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer). Inventory Inventory, Net Award Type [Domain] Award Type [Domain] Finance Lease, Interest Expense Finance Lease, Interest Expense Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Fair Value Measurements Fair Value Disclosures [Text Block] Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Reclassification of hedge gains, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term Percent of total assets at fair value Item As Percentage Of Total Assets At Fair Value Item as percentage of total assets at fair value Number of shares repurchased Treasury Stock, Shares, Acquired Gain (Loss) on Sale of Loans and Leases Gain (Loss) on Sale of Loans and Leases Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff Item As A Percent Of Total Auto Loans Held for Investment Item As A Percent Of Total Ending Managed Receivables Item As A Percent Of Total Ending Managed Receivables Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Activity Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Activity [Table Text Block] Share-Based Payment Arrangement, Stock-Settled Market Stock Units, Activity Service revenues Service [Domain] Service [Domain] Asset-Backed Securitization Program [Axis] Asset-Backed Securitization Program [Axis] Asset-Backed Securitization Program Entity Tax Identification Number Entity Tax Identification Number Past Due Financing Receivable, Past Due [Table Text Block] Legal Entity [Axis] Legal Entity [Axis] Changes in fair value, net of tax Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Cancellations SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction Financing Receivable, before Allowance for Credit Loss, Noncurrent Financing Receivable, before Allowance for Credit Loss, Noncurrent Share-Based Payment Arrangement, Expense, Tax Benefit Share-Based Payment Arrangement, Expense, Tax Benefit Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Warehouse Facility capacity increase Warehouse Facility capacity increase Warehouse Facility capacity increase Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Activity Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Activity [Table Text Block] Share-Based Payment Arrangement, Cash-Settled Restricted Stock Units, Activity Cash, cash equivalents, and restricted cash at beginning of year CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Restricted cash from collections on auto loans held for investment Restricted Cash and Cash Equivalent, Current Debt Instrument [Axis] Debt Instrument [Axis] Share-based compensation expense Share-Based Payment Arrangement, Noncash Expense Payroll and fringe benefit expense Labor and Related Expense Lease, Cost Lease, Cost Capitalized interest Interest Paid, Capitalized, Investing Activity Schedule Of Debt Schedule of Debt [Table Text Block] Employee stock purchase plan Employee Stock [Member] Warehouse Facilities Maximum Borrowing Capacity Warehouse Facilities Maximum Borrowing Capacity Maximum borrowing capacity under all warehouse facilities without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facilities. Other Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Basic (in dollars per share) Basic net earnings per share (in dollars per share) Earnings Per Share, Basic Transfer of auto loans held for sale Transfer of auto loans to held for sale [Member] Transfer of auto loans to held for sale Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award [Table Text Block] Repurchase and retirement of common stock Payments for Repurchase of Common Stock Cash payment per cash settled restricted stock unit Cash payment per cash settled restricted stock unit Cash payment per cash settled restricted stock unit Cash-settled restricted stock units (RSUs) Cash Settled Restricted Stock Units [Member] Cash-Settled Restricted Stock Units [Member] TOTAL CURRENT ASSETS  Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] TOTAL COST OF SALES Cost of Revenue Changes in fair value Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax Award Type [Axis] Award Type [Axis] PSU Second-year Period PSU Second-year Period [Member] PSU Second-year Period Fiscal 2026 Grant Fiscal 2026 Grant [Member] Fiscal 2026 Grant Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Schedule of Common Stock Repurchases Class of Treasury Stock [Table Text Block] Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff Retained earnings Retained Earnings (Accumulated Deficit) Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Schedule of Accumulated Other Comprehensive Loss [Table] Schedule of Accumulated Other Comprehensive Loss [Table] Schedule of Accumulated Other Comprehensive Loss [Table] Third-party finance fees, net Third-party finance fees [Domain] Third-party finance fees, net [Domain] Product and Service [Axis] Product and Service [Axis] Stock Settled Market Stock Units [Member] Stock Settled Market Stock Units [Member] Stock Settled Market Stock Units Schedule of Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value Schedule of Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Grant Date Intrinsic Value [Table Text Block] Cash Equivalent, Asset-Backed Security, Carrying Value Cash Equivalent, Asset-Backed Security, Carrying Value Asset-Backed Securitization Program [Domain] Asset-Backed Securitization Program [Domain] Asset-Backed Securitization Program [Domain] Total lease liabilities Total lease liabilities Combined liability for both operating and finance leases, current and noncurrent. Debt Instrument, Unused Borrowing Capacity, Amount Debt Instrument, Unused Borrowing Capacity, Amount Common Stock [Member] Common Stock [Member] Total lease assets Total lease assets Represents combined right of use asset for both operating and finance leases. Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Operating Lease, Cost Operating Lease, Cost Cover [Abstract] Cover [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY  Liabilities and Equity Stock options Share-Based Payment Arrangement, Option [Member] Debt, Current Debt, Current Other liabilities Increase (Decrease) in Other Operating Liabilities Warehouse Facility Three Warehouse Facility Three [Member] The third warehouse facility used to fund auto loan receivables originated by the entity. Plan Name [Axis] Plan Name [Axis] Auto Loans Held for Investment, Net Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] NET EARNINGS Net Earnings [Member] Net earnings Tier 2 & Tier 3 Tier 2 & Tier 3 managed receivables [Member] Tier 2 & Tier 3 managed receivables Leases of Lessee Disclosure [Text Block] (Deprecated 2026) Leases of Lessee Disclosure [Text Block] (Deprecated 2026) Vesting [Axis] Vesting [Axis] Restricted cash included in other assets Restricted Cash and Cash Equivalent, Noncurrent Capital in excess of par value Additional Paid in Capital Schedule of Funding Vehicles [Table Text Block] Schedule of Funding Vehicles [Table Text Block] [Table Text Block] for Schedule of Funding Vehicles [Table] Payroll and fringe benefit expense, percent Payroll And Fringe Benefit Expense [Member] Payroll And Fringe Benefit Expense [Member] Valuation Allowance [Line Items] Valuation Allowance [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate SHAREHOLDERS’ EQUITY: Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Purchases of investments Payments to Acquire Investments Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Greater Than Ninety Days Past Due [Member] Greater Than Ninety Days Past Due [Member] Greater Than Ninety Days Past Due [Member] Proceeds from Collection of Retained Interest in Securitized Receivables Proceeds from Collection of Retained Interest in Securitized Receivables Earnings before income taxes Earnings Before Income Taxes [Member] Earnings before income taxes Fiscal 2027 Grant Fiscal 2027 Grant [Member] Fiscal 2027 Grant Expected Cash Settlement Range Upon Cash Settled Restricted Stock Unit Vesting Expected Cash Settlement Range Upon Cash Settled Restricted Stock Unit Vesting [Table Text Block] Expected Cash Settlement Range Upon Cash Settled Restricted Stock Unit Vesting CarMax Auto Finance Auto Finance Income Loss [Text Block] Provides the disclosures pertaining to the income (loss) generated from the entity's financing of used and new vehicle retail sales, excluding the allocation of indirect costs or income. Amounts reclassified from accumulated other comprehensive loss Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Hedging Designation [Domain] Hedging Designation [Domain] Schedule of Carrying Values and Estimated Fair Values of Financing Receivables, Held-for-Sale Schedule of Carrying Values and Estimated Fair Values of Financing Receivables, Held-for-Sale [Table Text Block] Schedule of Carrying Values and Estimated Fair Values of Financing Receivables, Held-for-Sale Class of Stock [Domain] Class of Stock [Domain] Finance Lease, Interest Payment on Liability Finance Lease, Interest Payment on Liability Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Credit Facility [Axis] Credit Facility [Axis] Total assets at fair value Assets, Fair Value Disclosure Finance Lease, Liability, Payments, Due Year Five Finance Lease, Liability, to be Paid, Year Five Provision for loan losses, percent Provision For Loan Losses [Member] Provision For Loan Losses [Member] Business Combination, Consideration Transferred, Equity Interest, Type [Domain] Business Combination, Consideration Transferred, Equity Interest, Type [Domain] Income Taxes Income Tax Disclosure [Text Block] Accounts payable Accounts Payable, Current Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, to be Paid, Year Five Other share-based incentives Other share-based incentives [Member] Other share-based incentives, including stock-settled performance stock units, deferred stock units and restricted stock. Debt Instrument [Line Items] Debt Instrument [Line Items] Credit Grade C And Other Credit Grade C And Other [Member] Credit grade C member Other current assets Increase (Decrease) in Other Current Assets Interest and fee income Interest and Fee Income, Financing Receivable Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Supplemental Cash Flow Elements [Abstract] Supplemental Cash Flow Elements [Abstract] One to Thirty Days Past Due One to Thirty Days Past Due [Member] One to Thirty Days Past Due Goodwill, Impairment Loss Goodwill, Impairment Loss Restatement [Axis] Revision of Prior Period [Axis] Interest Receivable Interest Receivable Cash and cash equivalents Cash and Cash Equivalent Other comprehensive income (loss), net of taxes: Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent [Abstract] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures June 2026 Term Loan June 2026 Term Loan [Member] June 2026 Term Loan Basis of Presentation Basis of Accounting [Text Block] Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items] Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items] Schedule of Basic and Dilutive Net Earnings Per Share Reconciliation [Line Items] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Financial Asset, Period Past Due [Axis] Financial Asset, Aging [Axis] Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff October 2021 Term Loan October 2021 Term Loan [Member] October 2021 Term Loan Not Designated as Hedging Instrument [Member] Not Designated as Hedging Instrument [Member] Depreciation and amortization Depreciation, Depletion and Amortization Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Right-of-Use Asset Obtained in Exchange for Finance Lease Liability Right-of-Use Asset Obtained in Exchange for Finance Lease Liability CURRENT ASSETS: Assets, Current [Abstract] Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Remaining Lease Term Fiscal 2023 Grant Fiscal 2023 Grant [Member] Fiscal 2023 Grant Liabilities: Derivative instruments Derivative Liability Total amortization reclassifications recognized in net pension expense Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Senior Notes [Member] Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Income tax provision Income Tax Expense (Benefit) SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward] Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Minimum Proceeds from Legal Settlements Proceeds from Legal Settlements NET EARNINGS NET EARNINGS Net earnings Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Unamortized Debt Issuance Expense Unamortized Debt Issuance Expense Balance Sheet Location [Axis] Location, Statement of Financial Position, Balance [Axis] Proceeds from disposal of property and equipment Proceeds from Sale of Property, Plant, and Equipment Statement [Table] Statement [Table] Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Schedule of Accumulated Other Comprehensive Loss [Line Items] Schedule of Accumulated Other Comprehensive Loss [Line Items] Schedule of Accumulated Other Comprehensive Loss [Line Items] Proceeds from Stock Options Exercised Proceeds from Stock Options Exercised Changes In Accumulated Other Comprehensive Loss By Component Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Payments Upon Vesting Share-based Compensation Arrangement by Share-based Payment Award, Payments Upon Vesting Share-based Compensation Arrangement by Share-based Payment Award, Payments Upon Vesting Financing Receivable, Allowance for Credit Loss, Recovery Financing Receivable, Allowance for Credit Loss, Recovery Schedule Of Cancellation Reserves Accrual Contract Cancellation Reserve [Table Text Block] Contract Cancellation Reserve [Table Text Block] SALES AND OPERATING REVENUES: Revenues [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract]