CarMax Auto Finance (Components Of CarMax Auto Finance Income) (Details) - USD ($) $ in Thousands	3 Months Ended
	May 31, 2022	May 31, 2021
Auto Finance Income [Line Items]
Interest and fee income	$ 346,700	$ 310,300
Interest expense	(48,800)	(65,800)
Total interest margin	297,900	244,500
Provision for loan losses	(57,800)	24,400
Total interest margin after provision for loan losses	240,100	268,900
Payroll and fringe benefit expense	(14,700)	(12,600)
Other Depreciation and Amortization	(3,800)	(200)
Other direct expenses	(17,100)	(14,400)
Total direct expenses	(35,600)	(27,200)
CarMax Auto Finance income	204,473	241,731
Total average managed receivables	$ 15,817,000	$ 14,148,700
Interest and fee income, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	8.80%	8.80%
Interest expense, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(1.20%)	(1.90%)
Total interest margin, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	7.50%	6.90%
Provision for loan losses, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(1.50%)	0.70%
Total interest margin after provision for loan losses, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	6.10%	7.60%
Payroll and fringe benefit expense, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(0.40%)	(0.40%)
Other Depreciation and Amortization
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(0.10%)	0.00%
Other direct expenses, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(0.40%)	(0.40%)
Total direct expenses, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	(0.90%)	(0.80%)
CarMax Auto Finance income, percent
Auto Finance Income [Line Items]
Item as percent of total average managed receivables	5.20%	6.80%