Accounting Policies	9 Months Ended
Nov. 30, 2011
Accounting Policies [Abstract]
Accounting Policies	2. Accounting Policies Basis of Presentation and Use of Estimates. The accompanying interim unaudited consolidated financial statements include the accounts of CarMax and our wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. These consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles ("GAAP") for interim financial information. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, such interim consolidated financial statements reflect all normal recurring adjustments considered necessary to present fairly the financial position and the results of operations and cash flows for the interim periods presented. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full fiscal year. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and footnotes included in our Annual Report on Form 10-K for the fiscal year ended February 28, 2011. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. Certain prior year amounts have been reclassified to conform to the current year's presentation. Amounts and percentages may not total due to rounding. Cash and Cash Equivalents. Cash equivalents of $372.2 million as of November 30, 2011, and $23.9 million as of February 28, 2011, consisted of highly liquid investments with original maturities of three months or less. Restricted Cash from Collections on Auto Loan Receivables. Cash accounts totaling $174.4 million as of November 30, 2011, and $161.1 million as of February 28, 2011, consisted of collections of principal and interest payments on securitized auto loan receivables that are restricted for payment to the securitization investors pursuant to the applicable securitization agreements. Securitizations. As of March 1, 2010, we adopted Financial Accounting Standards Board ("FASB") Accounting Standards Update ("ASU") Nos. 2009-16 and 2009-17 (formerly Statements of Financial Accounting Standards Nos. 166 and 167, respectively) with prospective application. ASU No. 2009-16 amended FASB Accounting Standards Codification ("ASC") Topic 860, "Transfers and Servicing," and ASU No. 2009-17 amended FASB ASC Topic 810, "Consolidation." ASU No. 2009-16 removed the concept of a qualifying special-purpose entity ("QSPE") from Topic 860 and removed the provision within Topic 810 exempting these entities from consolidation. These pronouncements also clarified the requirements for isolation and the limitations on the portions of financial assets that are eligible for sale accounting treatment. Effective March 1, 2010, we recognize transfers of auto loan receivables into term securitizations as secured borrowings, which results in recording the auto loan receivables and the related non-recourse notes payable to the investors on our consolidated balance sheets. All transfers of receivables into our warehouse facilities on or after March 1, 2010, are also accounted for as secured borrowings. As of March 1, 2010, we amended our warehouse facility agreement in effect as of that date. As a result, auto loan receivables previously securitized through that warehouse facility no longer qualify for sale treatment because, under the amendment, CarMax now has effective control over the receivables. The receivables that were funded in the warehouse facility at that date were consolidated, at their fair value, along with the related non-recourse notes payable to the investors. Beginning in fiscal 2011, CAF income no longer includes a gain on the sale of loans through securitization transactions, but instead primarily reflects the interest and fee income generated by the auto loan receivables less the interest expense associated with the non-recourse notes payable issued to fund these receivables, direct CAF expenses and a provision for estimated loan losses. See Notes 3 and 5 for additional information on securitizations. Auto Loan Receivables, Net. Auto loan receivables include amounts due from customers primarily related to used retail vehicle sales financed through CAF and are presented net of an allowance for estimated loan losses. The allowance for loan losses represents an estimate of the amount of net losses inherent in our portfolio of managed receivables as of the applicable reporting date and anticipated to occur during the following 12 months. The allowance is primarily based on the credit quality of the underlying receivables, historical loss trends and forecasted forward loss curves. We also take into account recent trends in delinquencies and losses, recovery rates and the economic environment. The provision for loan losses is the periodic expense of maintaining an adequate allowance. An account is considered delinquent when the related customer fails to make a substantial portion of a scheduled payment on or before the due date. In general, accounts are charged-off on the last business day of the month during which the earliest of the following occurs: the receivable is 120 days or more delinquent as of the last business day of the month, the related vehicle is repossessed and liquidated or the receivable is otherwise deemed uncollectible. For purposes of determining impairment, auto loans are evaluated collectively, as they represent a large group of smaller-balance homogeneous loans, and therefore, are not individually evaluated for impairment. See Note 4 for additional information on auto loan receivables. Interest income and expenses related to auto loans are included in CAF income. Interest income on auto loan receivables is recognized when earned based on contractual loan terms. All loans continue to accrue interest until repayment or charge-off. Direct costs associated with loan originations are not considered material. See Note 3 for a summary of CAF income. Derivative Instruments and Hedging Activities. We enter into derivative instruments to manage exposures that arise from business activities that result in the future known receipt or payment of uncertain cash amounts, the values of which are impacted by interest rates. We recognize the derivatives at fair value as either current assets or current liabilities on the consolidated balance sheets. Where applicable, such contracts covered by master netting agreements are reported net. Gross positive fair values are netted with gross negative fair values by counterparty. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether we have elected to designate a derivative in a hedging relationship and apply hedge accounting, and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. We may enter into derivative contracts that are intended to economically hedge certain risks, even though hedge accounting may not apply or we do not elect to apply hedge accounting. See Note 6 for additional information on derivative instruments and hedging activities. Other Assets. Other assets includes amounts classified as restricted cash on deposit in reserve accounts and restricted investments. The restricted cash on deposit in reserve accounts is for the benefit of the securitization investors. In the event that the cash generated by the securitized receivables in a given period was insufficient to pay the interest, principal and other required payments, the balances on deposit in the reserve accounts would be used to pay those amounts. These funds are restricted for the benefit of holders of non-recourse notes payable and are not expected to be available to the company or its creditors. Restricted cash on deposit in reserve accounts was $41.5 million as of November 30, 2011, and $45.0 million as of February 28, 2011. See Note 5 for additional information on securitizations. Restricted investments includes money market securities primarily associated with certain insurance programs and mutual funds held in a rabbi trust established in May 2011 to fund informally our executive deferred compensation plan. Restricted investments was $30.8 million as of November 30, 2011, and $26.7 million as of February 28, 2011. Recent Accounting Pronouncements. In April 2011, the FASB issued an accounting pronouncement related to transfers and servicing (FASB ASC Topic 860), which removes the assessment of effective control criterion requiring the transferor to have the ability to repurchase or redeem the financial assets on substantially the agreed terms, even in the event of default by the transferee. The guidance in this pronouncement is effective prospectively for transactions, or modifications of existing transactions, that occur on or after the first interim or annual period beginning on or after December 15, 2011. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements. In May 2011, the FASB issued an accounting pronouncement related to fair value measurement (FASB ASC Topic 820), which amends current guidance to achieve common fair value measurement and disclosure requirements in U.S. GAAP and International Financial Reporting Standards. The amendments generally represent clarification of FASB ASC Topic 820, but also include instances where a particular principle or requirement for measuring fair value or disclosing information about fair value measurements has changed. This pronouncement is effective for fiscal years, and interim periods within those years, beginning after December 15, 2011. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements. In June 2011, the FASB issued an accounting pronouncement, as amended December 2011, that provides new guidance on the presentation of comprehensive income (FASB ASC Topic 220) in financial statements. Entities are required to present total comprehensive income either in a single, continuous statement of comprehensive income or in two separate, but consecutive, statements. Under the single-statement approach, entities must include the components of net income, a total for net income, the components of other comprehensive income and a total for comprehensive income. Under the two-statement approach, entities must report an income statement and, immediately following, a statement of other comprehensive income. Under either method, entities may present reclassification adjustments out of accumulated other comprehensive income on the face of the statement or disclose the reclassification adjustments in the notes to the financial statements. The provisions for this pronouncement as amended are effective for fiscal years, and interim periods within those years, beginning after December 15, 2011, with early adoption permitted. We will adopt this amended pronouncement for our fiscal year beginning March 1, 2012. In September 2011, the FASB issued an accounting pronouncement related to intangibles – goodwill and other (FASB ASC Topic 350), which allows for companies to first consider qualitative factors as a basis for assessing impairment and determining the necessity of a detailed impairment test. The provisions for this pronouncement are effective for fiscal years beginning after December 15, 2011, with early adoption permitted. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements. In December 2011, the FASB issued an accounting pronouncement related to offsetting of assets and liabilities on the balance sheet (FASB ASC Topic 210). The amendments require additional disclosures related to offsetting either in accordance with U.S. GAAP or master netting arrangements. The provisions for this pronouncement are effective for fiscal years, and interim periods within those years, beginning after January 1, 2013. We will adopt this pronouncement for our fiscal year beginning March 1, 2013.

2. Accounting Policies

Basis of Presentation and Use of Estimates. The accompanying interim unaudited consolidated financial statements include the accounts of CarMax and our wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. These consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles ("GAAP") for interim financial information. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, such interim consolidated financial statements reflect all normal recurring adjustments considered necessary to present fairly the financial position and the results of operations and cash flows for the interim periods presented. The results of operations for the interim periods are not necessarily indicative of the results to be expected for the full fiscal year. These consolidated financial statements should be read in conjunction with the audited consolidated financial statements and footnotes included in our Annual Report on Form 10-K for the fiscal year ended February 28, 2011.

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates. Certain prior year amounts have been reclassified to conform to the current year's presentation. Amounts and percentages may not total due to rounding.

Cash and Cash Equivalents. Cash equivalents of $372.2 million as of November 30, 2011, and $23.9 million as of February 28, 2011, consisted of highly liquid investments with original maturities of three months or less.

Restricted Cash from Collections on Auto Loan Receivables. Cash accounts totaling $174.4 million as of November 30, 2011, and $161.1 million as of February 28, 2011, consisted of collections of principal and interest payments on securitized auto loan receivables that are restricted for payment to the securitization investors pursuant to the applicable securitization agreements.

Securitizations. As of March 1, 2010, we adopted Financial Accounting Standards Board ("FASB") Accounting Standards Update ("ASU") Nos. 2009-16 and 2009-17 (formerly Statements of Financial Accounting Standards Nos. 166 and 167, respectively) with prospective application. ASU No. 2009-16 amended FASB Accounting Standards Codification ("ASC") Topic 860, "Transfers and Servicing," and ASU No. 2009-17 amended FASB ASC Topic 810, "Consolidation." ASU No. 2009-16 removed the concept of a qualifying special-purpose entity ("QSPE") from Topic 860 and removed the provision within Topic 810 exempting these entities from consolidation. These pronouncements also clarified the requirements for isolation and the limitations on the portions of financial assets that are eligible for sale accounting treatment.

Effective March 1, 2010, we recognize transfers of auto loan receivables into term securitizations as secured borrowings, which results in recording the auto loan receivables and the related non-recourse notes payable to the investors on our consolidated balance sheets. All transfers of receivables into our warehouse facilities on or after March 1, 2010, are also accounted for as secured borrowings. As of March 1, 2010, we amended our warehouse facility agreement in effect as of that date. As a result, auto loan receivables previously securitized through that warehouse facility no longer qualify for sale treatment because, under the amendment, CarMax now has effective control over the receivables. The receivables that were funded in the warehouse facility at that date were consolidated, at their fair value, along with the related non-recourse notes payable to the investors.

Beginning in fiscal 2011, CAF income no longer includes a gain on the sale of loans through securitization transactions, but instead primarily reflects the interest and fee income generated by the auto loan receivables less the interest expense associated with the non-recourse notes payable issued to fund these receivables, direct CAF expenses and a provision for estimated loan losses. See Notes 3 and 5 for additional information on securitizations.

Auto Loan Receivables, Net. Auto loan receivables include amounts due from customers primarily related to used retail vehicle sales financed through CAF and are presented net of an allowance for estimated loan losses. The allowance for loan losses represents an estimate of the amount of net losses inherent in our portfolio of managed receivables as of the applicable reporting date and anticipated to occur during the following 12 months. The allowance is primarily based on the credit quality of the underlying receivables, historical loss trends and forecasted forward loss curves. We also take into account recent trends in delinquencies and losses, recovery rates and the economic environment. The provision for loan losses is the periodic expense of maintaining an adequate allowance.

An account is considered delinquent when the related customer fails to make a substantial portion of a scheduled payment on or before the due date. In general, accounts are charged-off on the last business day of the month during which the earliest of the following occurs: the receivable is 120 days or more delinquent as of the last business day of the month, the related vehicle is repossessed and liquidated or the receivable is otherwise deemed uncollectible. For purposes of determining impairment, auto loans are evaluated collectively, as they represent a large group of smaller-balance homogeneous loans, and therefore, are not individually evaluated for impairment. See Note 4 for additional information on auto loan receivables.

Interest income and expenses related to auto loans are included in CAF income. Interest income on auto loan receivables is recognized when earned based on contractual loan terms. All loans continue to accrue interest until repayment or charge-off. Direct costs associated with loan originations are not considered material. See Note 3 for a summary of CAF income.

Derivative Instruments and Hedging Activities. We enter into derivative instruments to manage exposures that arise from business activities that result in the future known receipt or payment of uncertain cash amounts, the values of which are impacted by interest rates. We recognize the derivatives at fair value as either current assets or current liabilities on the consolidated balance sheets. Where applicable, such contracts covered by master netting agreements are reported net. Gross positive fair values are netted with gross negative fair values by counterparty. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative, whether we have elected to designate a derivative in a hedging relationship and apply hedge accounting, and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. We may enter into derivative contracts that are intended to economically hedge certain risks, even though hedge accounting may not apply or we do not elect to apply hedge accounting. See Note 6 for additional information on derivative instruments and hedging activities.

Other Assets. Other assets includes amounts classified as restricted cash on deposit in reserve accounts and restricted investments. The restricted cash on deposit in reserve accounts is for the benefit of the securitization investors. In the event that the cash generated by the securitized receivables in a given period was insufficient to pay the interest, principal and other required payments, the balances on deposit in the reserve accounts would be used to pay those amounts. These funds are restricted for the benefit of holders of non-recourse notes payable and are not expected to be available to the company or its creditors. Restricted cash on deposit in reserve accounts was $41.5 million as of November 30, 2011, and $45.0 million as of February 28, 2011. See Note 5 for additional information on securitizations.

Restricted investments includes money market securities primarily associated with certain insurance programs and mutual funds held in a rabbi trust established in May 2011 to fund informally our executive deferred compensation plan. Restricted investments was $30.8 million as of November 30, 2011, and $26.7 million as of February 28, 2011.

Recent Accounting Pronouncements. In April 2011, the FASB issued an accounting pronouncement related to transfers and servicing (FASB ASC Topic 860), which removes the assessment of effective control criterion requiring the transferor to have the ability to repurchase or redeem the financial assets on substantially the agreed terms, even in the event of default by the transferee. The guidance in this pronouncement is effective prospectively for transactions, or modifications of existing transactions, that occur on or after the first interim or annual period beginning on or after December 15, 2011. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements.

In May 2011, the FASB issued an accounting pronouncement related to fair value measurement (FASB ASC Topic 820), which amends current guidance to achieve common fair value measurement and disclosure requirements in U.S. GAAP and International Financial Reporting Standards. The amendments generally represent clarification of FASB ASC Topic 820, but also include instances where a particular principle or requirement for measuring fair value or disclosing information about fair value measurements has changed. This pronouncement is effective for fiscal years, and interim periods within those years, beginning after December 15, 2011. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements.

In June 2011, the FASB issued an accounting pronouncement, as amended December 2011, that provides new guidance on the presentation of comprehensive income (FASB ASC Topic 220) in financial statements. Entities are required to present total comprehensive income either in a single, continuous statement of comprehensive income or in two separate, but consecutive, statements. Under the single-statement approach, entities must include the components of net income, a total for net income, the components of other comprehensive income and a total for comprehensive income. Under the two-statement approach, entities must report an income statement and, immediately following, a statement of other comprehensive income. Under either method, entities may present reclassification adjustments out of accumulated other comprehensive income on the face of the statement or disclose the reclassification adjustments in the notes to the financial statements. The provisions for this pronouncement as amended are effective for fiscal years, and interim periods within those years, beginning after December 15, 2011, with early adoption permitted. We will adopt this amended pronouncement for our fiscal year beginning March 1, 2012.

In September 2011, the FASB issued an accounting pronouncement related to intangibles – goodwill and other (FASB ASC Topic 350), which allows for companies to first consider qualitative factors as a basis for assessing impairment and determining the necessity of a detailed impairment test. The provisions for this pronouncement are effective for fiscal years beginning after December 15, 2011, with early adoption permitted. We will adopt this pronouncement for our fiscal year beginning March 1, 2012. We do not expect this pronouncement to have a material effect on our consolidated financial statements.

In December 2011, the FASB issued an accounting pronouncement related to offsetting of assets and liabilities on the balance sheet (FASB ASC Topic 210). The amendments require additional disclosures related to offsetting either in accordance with U.S. GAAP or master netting arrangements. The provisions for this pronouncement are effective for fiscal years, and interim periods within those years, beginning after January 1, 2013. We will adopt this pronouncement for our fiscal year beginning March 1, 2013.