Auto Loan Receivables (Auto Loan Receivables, Net) (Details) (USD $)	Nov. 30, 2013		Aug. 31, 2013	Feb. 28, 2013		Nov. 30, 2012	Aug. 31, 2012	Feb. 29, 2012
Non-recourse notes payable	$ 6,970,000,000			$ 5,860,000,000
Total ending managed receivables	6,919,000,000	[1],[2]		5,933,300,000	[1],[2]
Accrued interest and fees	29,100,000			24,900,000
Other	12,100,000			(5,000,000)
Less allowance for loan losses	(67,900,000)		(65,900,000)	(57,300,000)		(54,300,000)	(49,500,000)	(43,300,000)
Auto loan receivables, net	6,892,311,000			5,895,918,000
Warehouse Facilities Receivables [Member]
Total ending managed receivables	807,000,000			792,000,000
Term securitizations [Member]
Total ending managed receivables	5,948,500,000			4,989,700,000
Other receivables [Member]
Total ending managed receivables	$ 163,500,000			$ 151,600,000

[1] Other receivables includes receivables not funded through the warehouse facilities or term securitizations.

[2] Classified based on credit grade assigned when customers were initially approved for financing.