Auto Loan Receivables (Allowance For Loan Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance as of beginning of period	$ 109.7	$ 87.8	$ 94.9	$ 81.7
Charge-offs	(62.9)	(51.9)	(164.6)	(128.7)
Recoveries	26.1	24.1	80.3	67.7
Provision for loan losses	41.9	30.9	104.2	70.2
Balance as of end of period	$ 114.8	$ 90.9	$ 114.8	$ 90.9
Allowance For Loan Losses, percent
Financing Receivable, Allowance for Credit Losses [Line Items]
Item as percent of total ending managed receivables, balance as of beginning of period	1.08%	0.96%	0.99%	0.97%
Item as percent of total ending managed receivables, balance as of end of period	1.10%	0.97%	1.10%	0.97%