CarMax Auto Finance (Components Of CarMax Auto Finance Income) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Aug. 31, 2025	Aug. 31, 2024	Aug. 31, 2025	Aug. 31, 2024
Auto Finance Income [Line Items]
Interest and fee income	$ 489,800	$ 464,500	$ 975,200	$ 917,000
Interest expense	(199,200)	(193,700)	(396,700)	(376,000)
Total interest margin	290,600	270,800	578,500	541,000
Provision for loan losses	(142,200)	(112,600)	(243,904)	(193,798)
Total interest margin after provision for loan losses	148,400	158,200	334,600	347,200
Payroll and fringe benefit expense	(20,500)	(19,000)	(40,500)	(37,600)
Other Depreciation and Amortization	(4,400)	(4,300)	(8,700)	(8,500)
Other direct expenses	(20,900)	(19,300)	(41,100)	(38,500)
Total direct expenses	(45,800)	(42,600)	(90,300)	(84,600)
CarMax Auto Finance income	$ 102,638	$ 115,580	$ 244,288	$ 262,550