Segment Reporting (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Nov. 30, 2022	Nov. 30, 2021	Nov. 30, 2022	Nov. 30, 2021
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	$ 6,505,956	$ 8,527,759	$ 23,962,380	$ 24,213,717
Depreciation and amortization			202,655	200,819
Gross Profit	576,688	836,560	2,189,224	2,576,553
CARMAX AUTO FINANCE INCOME	152,196	165,968	539,538	607,732
Selling, General and Administrative Expense	(591,727)	(575,930)	(1,914,508)	(1,704,285)
Depreciation, Depletion and Amortization, Nonproduction	(57,377)	(54,428)	(170,717)	(157,107)
Interest expense	(30,150)	(24,303)	(91,670)	(67,247)
Other income	363	8,094	2,303	35,453
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	49,993	$ 355,961	554,170	$ 1,291,099
TOTAL COST OF SALES
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	4,139		11,291
Intersegment Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	(5,549)		(20,219)
Gross Profit	(1,149)		(4,276)
CarMax Sales Operations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	6,472,702		23,860,462
Gross Profit	554,057		2,115,631
CarMax Sales Operations | TOTAL COST OF SALES
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	404		1,092
CarMax Sales Operations | Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	6,472,702		23,860,462
Other Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	33,254		101,918
Gross Profit	23,780		77,869
Other Segments | TOTAL COST OF SALES
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation and amortization	3,735		10,199
Other Segments | Intersegment Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	5,549		20,219
Other Segments | Operating Segments
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
NET SALES AND OPERATING REVENUES	$ 38,803		$ 122,137