Accumulated Other Comprehensive Loss (Changes In and Reclassifications Out of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Nov. 30, 2021	Nov. 30, 2020	Nov. 30, 2021	Nov. 30, 2020
Total amortization reclassifications recognized in net pension expense	$ 869	$ 959	$ 2,605	$ 2,878
Tax expense	(210)	(232)	(629)	(695)
Amortization reclassifications recognized in net pension expense, net of tax	659	727	1,976	2,183
Net change in retirement benefit plan unrecognized actuarial losses, net of tax	659	727	1,976	2,183
Changes in fair value	11,339	2,877	8,668	(21,906)
Tax (expense) benefit	(2,985)	(761)	(2,282)	5,793
Changes in fair value, net of tax	8,354	2,116	6,386	(16,113)
Reclassifications to CarMax Auto Finance income	4,111	6,334	13,610	15,060
Tax expense	(1,082)	(1,675)	(3,582)	(3,983)
Reclassification of hedge losses, net of tax	3,029	4,659	10,028	11,077
Net change in cash flow hedge unrecognized losses, net of tax	11,383	6,775	16,414	(5,036)
Total other comprehensive income (loss), net of tax	12,042	7,502	18,390	(2,853)
Cost of sales
Total amortization reclassifications recognized in net pension expense	367	402	1,083	1,212
CarMax Auto Finance income
Total amortization reclassifications recognized in net pension expense	21	27	64	83
Selling, general and administrative expenses
Total amortization reclassifications recognized in net pension expense	$ 481	$ 530	$ 1,458	$ 1,583