Inventories (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Inventory [Line Items]
Inventories, net		$ 1,976.0
Truck, Parts and Other
Inventory [Line Items]
Finished products	$ 749.9	676.0
Work in process and raw materials	1,472.2	1,300.0
Inventories, net	$ 2,222.1	$ 1,976.0

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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