Auto Loan Receivables (Allowance For Loan Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018	Aug. 31, 2019	Feb. 28, 2019	Aug. 31, 2018	Feb. 28, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of beginning of period	$ 150.4	$ 138.1	$ 138.2	$ 128.6
Charge-offs	(81.2)	(74.3)	(223.4)	(198.1)
Recoveries	35.4	33.7	106.1	96.1
Provision for loan losses	49.0	40.8	132.7	111.7
Balance as of end of period	$ 153.6	$ 138.3	$ 153.6	$ 138.3
Allowance For Loan Losses, percent
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Item as percent of total ending managed receivables	1.15%	1.12%	1.15%	1.12%	1.15%	1.10%	1.13%	1.11%