Auto Loan Receivables (Auto Loan Receivables, Net) (Details) - USD ($) $ in Thousands	Aug. 31, 2023	May 31, 2023	Feb. 28, 2023	Aug. 31, 2022	May 31, 2022	Feb. 28, 2022
Non-recourse Notes Payable	$ 17,007,618		$ 16,360,092
Financing Receivable, before Allowance for Credit Loss	17,442,800		16,767,900
Interest Receivable	97,300		78,000
Other	(2,300)		3,100
Financing Receivable, Allowance for Credit Loss	538,018	$ 535,400	507,201	$ 477,500	$ 458,200	$ 433,000
Financing Receivable, after Allowance for Credit Loss	16,999,750		16,341,791
Asset-backed term funding
Financing Receivable, before Allowance for Credit Loss	12,080,600		12,242,800
Warehouse facilities
Financing Receivable, before Allowance for Credit Loss	4,419,600		3,649,900
Overcollateralization
Financing Receivable, before Allowance for Credit Loss	783,200		739,900
Other managed receivables
Financing Receivable, before Allowance for Credit Loss	$ 159,400		$ 135,300