Estimated Value of Returned Goods Assets and Related Return Liabilities (Detail) - Truck, Parts and Other - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Trucks | ||
| Entity Wide Information Revenue From External Customer [Line Items] | ||
| Other current assets | $ 64.1 | $ 83.1 |
| Accounts payable, accrued expenses and other | 66.7 | 87.2 |
| Other noncurrent assets, net | 236.9 | 195.2 |
| Other liabilities | 245.4 | 203.0 |
| Assets | 301.0 | 278.3 |
| Liabilities | 312.1 | 290.2 |
| Parts Subsegment | ||
| Entity Wide Information Revenue From External Customer [Line Items] | ||
| Other current assets | 97.5 | 97.0 |
| Accounts payable, accrued expenses and other | 239.4 | 239.6 |
| Assets | 97.5 | 97.0 |
| Liabilities | $ 239.4 | $ 239.6 |