Inventories (Detail) - Truck, Parts and Other - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Inventory [Line Items]
Finished products	$ 1,022.5	$ 871.8
Work in process and raw materials	1,586.7	1,327.0
Inventories, net	$ 2,609.2	$ 2,198.8

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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(6)(a)(1))
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02(6))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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