Accumulated Other Comprehensive Loss (Changes In and Reclassifications Out of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2021
Actuarial gain arising during the year	$ 34,836	$ 22,517	$ 33,913
Tax expense	(8,359)	(5,483)	(8,184)
Actuarial gain arising during the year, net of tax	26,477	17,034	25,729
Actuarial loss amortization reclassifications in net pension expense	2,545	3,473	3,837
Tax expense	(611)	(846)	(926)
Amortization reclassifications recognized in net pension expense, net of tax	1,934	2,627	2,911
Net change in retirement benefit plan unrecognized actuarial losses, net of tax	28,411	19,661	28,640
Changes in fair value	180,510	54,105	(17,122)
Tax (expense) benefit	(44,318)	(13,894)	4,506
Changes in fair value, net of tax	136,192	40,211	(12,616)
Reclassifications to CarMax Auto Finance income	(26,859)	16,680	20,841
Tax benefit (expense)	6,547	(4,283)	(5,485)
Reclassification of hedge (gains) losses, net of tax	(20,312)	12,397	15,356
Net change in cash flow hedge unrecognized gains, net of tax	115,880	52,608	2,740
Total other comprehensive income, net of tax	144,291	72,269	31,380
TOTAL COST OF SALES
Actuarial loss amortization reclassifications in net pension expense	1,084	1,451	1,617
CarMax Auto Finance income
Actuarial loss amortization reclassifications in net pension expense	70	84	108
Selling, general and administrative expenses
Actuarial loss amortization reclassifications in net pension expense	$ 1,391	$ 1,938	$ 2,112