Contractual Maturities of Marketable Debt Securities (Detail) - Truck, Parts and Other $ in Millions	Dec. 31, 2022 USD ($)
Amortized Cost Maturities:
Within one year	$ 447.5
One to five years	1,207.2
Six to ten years	3.3
More than ten years	13.1
Marketable debt securities, Cost	1,671.1
Fair Value Maturities:
Within one year	442.4
One to five years	1,155.8
Six to ten years	3.3
More than ten years	11.5
Fair Value	$ 1,613.0

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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