v3.26.1
Auto Loans Held for Investment (By Major Credit Grade) (Details) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
May 31, 2026
May 31, 2025
Feb. 28, 2026
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year $ 2,136.7   $ 6,125.8
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 5,300.7   4,388.2
Financing Receivable, Originated Two Years before Latest Fiscal Year 3,913.8   2,940.4
Financing Receivable, Originated Three Years before Latest Fiscal Year 2,549.6   1,824.2
Financing Receivable, Originated Four Years before Latest Fiscal Year 1,511.0   842.0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 686.7   151.3
Financing Receivable, before Allowance for Credit Loss $ 16,098.5   $ 16,271.9
Total ending managed receivables as percentage by major credit grade 100.00%   100.00%
Financing Receivable, Allowance for Credit Loss, Writeoff $ 133.9 $ 141.7 $ 636.1
Financing Receivable, Year Three, Originated, Two Years before Current Fiscal Year, Writeoff 31.7   183.5
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year, Writeoff 28.9   153.7
Financing Receivable, Year Four, Originated, Three Years before Current Fiscal Year, Writeoff 34.0   152.5
Financing Receivable, Year Five, Originated, Four Years before Current Fiscal Year, Writeoff 25.5   78.3
Financing Receivable, Originated, More than Five Years before Current Fiscal Year, Writeoff 13.7   25.2
Financing Receivable, Year One, Originated, Current Fiscal Year, Writeoff 0.1   42.9
Tier 1      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year 1,922.8   5,942.1
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 5,126.9   4,216.2
Financing Receivable, Originated Two Years before Latest Fiscal Year 3,759.2   2,832.3
Financing Receivable, Originated Three Years before Latest Fiscal Year 2,454.5   1,762.9
Financing Receivable, Originated Four Years before Latest Fiscal Year 1,459.1   819.8
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 668.4   148.2
Financing Receivable, before Allowance for Credit Loss $ 15,390.9   $ 15,721.5
Total ending managed receivables as percentage by major credit grade 95.60%   96.60%
Financing Receivable, Allowance for Credit Loss, Writeoff $ 115.1 120.2  
Tier 2 & Tier 3      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Allowance for Credit Loss, Writeoff 18.8 $ 21.5  
Credit Grade A | Tier 1      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year 1,306.1   $ 3,871.5
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 3,481.8   2,738.1
Financing Receivable, Originated Two Years before Latest Fiscal Year 2,434.8   1,578.8
Financing Receivable, Originated Three Years before Latest Fiscal Year 1,352.3   887.9
Financing Receivable, Originated Four Years before Latest Fiscal Year 719.5   352.4
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 272.5   45.2
Financing Receivable, before Allowance for Credit Loss $ 9,567.0   $ 9,473.9
Total ending managed receivables as percentage by major credit grade 59.40%   58.20%
Credit Grade B | Tier 1      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year $ 529.4   $ 1,643.7
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 1,311.2   1,233.9
Financing Receivable, Originated Two Years before Latest Fiscal Year 1,105.0   1,075.2
Financing Receivable, Originated Three Years before Latest Fiscal Year 945.3   687.0
Financing Receivable, Originated Four Years before Latest Fiscal Year 580.3   352.0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 289.8   65.0
Financing Receivable, before Allowance for Credit Loss $ 4,761.0   $ 5,056.8
Total ending managed receivables as percentage by major credit grade 29.60%   31.10%
Credit Grade C And Other | Tier 1      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year $ 87.3   $ 426.9
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 333.9   244.2
Financing Receivable, Originated Two Years before Latest Fiscal Year 219.4   178.3
Financing Receivable, Originated Three Years before Latest Fiscal Year 156.9   188.0
Financing Receivable, Originated Four Years before Latest Fiscal Year 159.3   115.4
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 106.1   38.0
Financing Receivable, before Allowance for Credit Loss $ 1,062.9   $ 1,190.8
Total ending managed receivables as percentage by major credit grade 6.60%   7.30%
Credit Grade C And Other | Tier 2 & Tier 3      
Financing Receivable, By Major Credit Grade [Line Items]      
Financing Receivable, Originated in Current Fiscal Year $ 213.9   $ 183.7
Financing Receivable, Originated in Fiscal Year before Latest Fiscal Year 173.8   172.0
Financing Receivable, Originated Two Years before Latest Fiscal Year 154.6   108.1
Financing Receivable, Originated Three Years before Latest Fiscal Year 95.1   61.3
Financing Receivable, Originated Four Years before Latest Fiscal Year 51.9   22.2
Financing Receivable, Originated Five or More Years before Latest Fiscal Year 18.3   3.1
Financing Receivable, before Allowance for Credit Loss $ 707.6   $ 550.4
Total ending managed receivables as percentage by major credit grade 4.40%   3.40%