v3.26.1
Finance Receivables within Credit Quality Indicator and Portfolio Class (Detail) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans $ 2,559.8   $ 2,669.3
2026 515.6   3,044.4
2025 2,919.4   2,393.2
2024 2,250.7   1,624.4
2023 1,488.5   859.5
2022 737.4   315.3
Prior 369.4   152.0
Total 10,840.8   11,058.1
Total 16.0 $ 11.7  
Dealer      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 2,559.8   2,669.3
2026 80.1   517.9
2025 494.6   497.2
2024 472.5   444.0
2023 413.5   285.8
2022 264.7   127.5
Prior 198.8   106.7
Total 4,484.0   4,648.4
Dealer | Wholesale      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 2,330.4   2,440.8
Total 2,330.4   2,440.8
Dealer | Wholesale | Performing      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 2,325.1   2,437.6
Total 2,325.1   2,437.6
Dealer | Wholesale | Watch      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 5.3   3.2
Total 5.3   3.2
Dealer | Retail      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 229.4   228.5
2026 80.1   517.9
2025 494.6   497.2
2024 472.5   444.0
2023 413.5   285.8
2022 264.7   127.5
Prior 198.8   106.7
Total 2,153.6   2,207.6
Dealer | Retail | Performing      
Financing Receivable Recorded Investment [Line Items]      
Revolving Loans 229.4   228.5
2026 80.1   517.9
2025 494.6   497.2
2024 472.5   444.0
2023 413.5   285.8
2022 264.7   127.5
Prior 198.8   106.7
Total 2,153.6   2,207.6
Customer Retail      
Financing Receivable Recorded Investment [Line Items]      
2026 435.5   2,526.5
2025 2,424.8   1,896.0
2024 1,778.2   1,180.4
2023 1,075.0   573.7
2022 472.7   187.8
Prior 170.6   45.3
Total 6,356.8   6,409.7
Total 15.7 $ 11.7  
Customer Retail | Gross Charge-Offs      
Financing Receivable Recorded Investment [Line Items]      
Current Fiscal Year     0.2
Fiscal Year before Current Fiscal Year 1.7   7.4
Two Years before Current Fiscal Year 1.7   22.7
Three Years before Current Fiscal Year 7.0   11.2
Four Years before Current Fiscal Year 3.6   2.6
Prior 1.7   0.4
Total 15.7   44.5
Customer Retail | Fleet      
Financing Receivable Recorded Investment [Line Items]      
2026 378.4   2,247.3
2025 2,156.6   1,723.9
2024 1,617.4   1,109.5
2023 1,012.1   524.9
2022 432.9   162.8
Prior 149.8   39.9
Total 5,747.2   5,808.3
Customer Retail | Fleet | Performing      
Financing Receivable Recorded Investment [Line Items]      
2026 367.8   2,188.6
2025 2,070.8   1,693.1
2024 1,549.5   973.7
2023 853.9   463.2
2022 371.1   145.8
Prior 132.1   38.7
Total 5,345.2   5,503.1
Customer Retail | Fleet | Watch      
Financing Receivable Recorded Investment [Line Items]      
2026 9.4   48.3
2025 64.9   16.0
2024 21.0   51.6
2023 37.2   40.7
2022 31.7   14.8
Prior 13.0   0.6
Total 177.2   172.0
Customer Retail | Fleet | At-risk      
Financing Receivable Recorded Investment [Line Items]      
2026 1.2   10.4
2025 20.9   14.8
2024 46.9   84.2
2023 121.0   21.0
2022 30.1   2.2
Prior 4.7   0.6
Total 224.8   133.2
Customer Retail | Fleet | Gross Charge-Offs      
Financing Receivable Recorded Investment [Line Items]      
Fiscal Year before Current Fiscal Year 1.6   6.2
Two Years before Current Fiscal Year 1.1   21.2
Three Years before Current Fiscal Year 6.7   9.9
Four Years before Current Fiscal Year 3.0   2.4
Prior 1.6   0.2
Total 14.0   39.9
Customer Retail | Owner/Operator      
Financing Receivable Recorded Investment [Line Items]      
2026 57.1   279.2
2025 268.2   172.1
2024 160.8   70.9
2023 62.9   48.8
2022 39.8   25.0
Prior 20.8   5.4
Total 609.6   601.4
Customer Retail | Owner/Operator | Performing      
Financing Receivable Recorded Investment [Line Items]      
2026 57.1   275.6
2025 264.9   168.3
2024 158.1   68.3
2023 60.1   44.4
2022 37.7   23.7
Prior 19.3   5.0
Total 597.2   585.3
Customer Retail | Owner/Operator | Watch      
Financing Receivable Recorded Investment [Line Items]      
2026     2.4
2025 1.5   2.2
2024 1.7   1.8
2023 2.4   2.4
2022 0.8   0.9
Prior 0.9   0.2
Total 7.3   9.9
Customer Retail | Owner/Operator | At-risk      
Financing Receivable Recorded Investment [Line Items]      
2026     1.2
2025 1.8   1.6
2024 1.0   0.8
2023 0.4   2.0
2022 1.3   0.4
Prior 0.6   0.2
Total 5.1   6.2
Customer Retail | Owner/Operator | Gross Charge-Offs      
Financing Receivable Recorded Investment [Line Items]      
Current Fiscal Year     0.2
Fiscal Year before Current Fiscal Year 0.1   1.2
Two Years before Current Fiscal Year 0.6   1.5
Three Years before Current Fiscal Year 0.3   1.3
Four Years before Current Fiscal Year 0.6   0.2
Prior 0.1   0.2
Total $ 1.7   $ 4.6