Auto Loan Receivables (Auto Loan Receivables, Net) (Details) - USD ($) $ in Thousands	Nov. 30, 2019	Aug. 31, 2019	Feb. 28, 2019	Nov. 30, 2018	Aug. 31, 2018	Feb. 28, 2018
Non-recourse notes payable	$ 13,320,447		$ 12,535,405
Total ending managed receivables	13,352,600		12,510,200
Accrued interest and fees	59,900		49,600
Other	17,800		6,900
Less allowance for loan losses	(153,600)	$ (150,400)	(138,200)	$ (138,300)	$ (138,100)	$ (128,600)
Auto loan receivables, net	13,276,654		12,428,487
Asset-backed term funding
Total ending managed receivables	10,616,900		10,273,400
Warehouse facilities
Total ending managed receivables	2,305,700		1,877,000
Overcollateralization
Total ending managed receivables	296,300		273,300
Other managed receivables
Total ending managed receivables	$ 133,700		$ 86,500