Accumulated Other Comprehensive Loss (Changes In and Reclassifications Out of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2021	Aug. 31, 2020
Total amortization reclassifications recognized in net pension expense	$ 868	$ 960	$ 1,736	$ 1,919
Tax expense	(210)	(232)	(419)	(463)
Amortization reclassifications recognized in net pension expense, net of tax	658	728	1,317	1,456
Net change in retirement benefit plan unrecognized actuarial losses, net of tax	658	728	1,317	1,456
Changes in fair value	(665)	79	(2,671)	(24,783)
Tax benefit (expense)	175	(21)	703	6,554
Changes in fair value, net of tax	(490)	58	(1,968)	(18,229)
Reclassifications to CarMax Auto Finance income	4,401	5,701	9,499	8,726
Tax expense	(1,158)	(1,508)	(2,500)	(2,308)
Reclassification of hedge losses, net of tax	3,243	4,193	6,999	6,418
Net change in cash flow hedge unrecognized losses, net of tax	2,753	4,251	5,031	(11,811)
Total other comprehensive income (loss), net of tax	3,411	4,979	6,348	(10,355)
Cost of sales
Total amortization reclassifications recognized in net pension expense	359	437	716	810
CarMax Auto Finance income
Total amortization reclassifications recognized in net pension expense	21	25	43	56
Selling, general and administrative expenses
Total amortization reclassifications recognized in net pension expense	$ 488	$ 498	$ 977	$ 1,053