v3.25.2
Marketable Debt Securities Continuous Unrealized Losses (Detail) - Truck, Parts and Other - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Schedule Of Available For Sale Securities [Line Items]    
Less than 12 Months Unrealized Losses $ 0.3 $ 5.5
Less than 12 Months Fair Value 238.6 932.9
12 Months or Greater Unrealized losses 2.4 6.2
12 Months or Greater Fair value $ 164.5 $ 365.5