Intangible Assets, Goodwill and Other (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 28, 2022	Feb. 28, 2021
Internally developed software
Schedule of Intangible Assets (Finite-Lived and Indefinite-Lived) [Line Items]
Finite-Lived Intangible Assets, Gross	$ 52,900
Finite-Lived Intangible Assets, Accumulated Amortization	(5,668)
Finite-Lived Intangible Assets, Net	47,232
Customer Relationships
Schedule of Intangible Assets (Finite-Lived and Indefinite-Lived) [Line Items]
Finite-Lived Intangible Assets, Gross	133,200
Finite-Lived Intangible Assets, Accumulated Amortization	(5,876)
Finite-Lived Intangible Assets, Net	127,324
Goodwill	141,258	$ 653
Indefinite-lived Intangible Assets (Excluding Goodwill)	31,900
Intangible Assets, Gross (Excluding Goodwill)	218,000
Finite-Lived Intangible Assets, Accumulated Amortization	(11,544)
Intangible Assets, Net (Excluding Goodwill)	206,456
Amortization of Intangible Assets	11,500
Finite-Lived Intangible Asset, Expected Amortization, Year One	15,400
Finite-Lived Intangible Asset, Expected Amortization, Year Two	15,400
Finite-Lived Intangible Asset, Expected Amortization, Year Three	15,400
Finite-Lived Intangible Asset, Expected Amortization, Year Five	15,400
Finite-Lived Intangible Asset, Expected Amortization, Year Four	15,400
CarMax Sales Operations
Goodwill [Line Items]
Goodwill	98,900
Edmunds
Goodwill [Line Items]
Goodwill	$ 42,400

Schedule of Intangible Assets (Finite-Lived and Indefinite-Lived) [Line Items]

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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