Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	May 31, 2020	May 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 3,228.8	$ 5,366.3
Used vehicle sales
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	2,786.2	4,540.7
Wholesale vehicle sales
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	342.9	662.4
Extended protection plan revenues
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	73.4	111.3
Third-party finance fees, net
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	(10.7)	(15.5)
Service revenues
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	19.5	34.0
Other
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	17.5	33.4
Total other sales and revenues
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 99.7	$ 163.2