Changes in Product Support Liabilities (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
DEFERRED REVENUES ON EXTENDED WARRANTIES AND R&M CONTRACTS
Beginning balance	$ 1,302.2	$ 1,229.1
Deferred revenues	172.7	177.7
Revenues recognized	(157.9)	(141.4)
Currency translation	26.5	(11.8)
Ending balance	1,343.5	1,253.6
Truck, Parts and Other
WARRANTY RESERVES
Beginning balance	606.1	767.0
Cost accruals	199.5	181.3
Payments	(211.3)	(220.8)
Change in estimates for pre-existing warranties	19.2	41.8
Currency translation and other	8.9	(5.9)
Ending balance	$ 622.4	$ 763.4

Extended product warranty beginning balance.

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- Definition

Extended product warranty currency translation.

+ References

No definition available.

+ Details

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- Definition

Extended product warranty deferred revenues.

+ References

No definition available.

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- Definition

Extended product warranty ending balance.

+ References

No definition available.

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- Definition

Extended product warranty revenues recognized.

+ References

No definition available.

+ Details

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- Definition

Movement in extended product warranty.

+ References

No definition available.

+ Details

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- Definition

Standard product warranty accrual currency translation and other.

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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- Definition

Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties.

+ References

+ Details

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- Definition

Amount of increase (decrease) in the standard product warranty accrual from changes in estimates attributable to preexisting product warranties. Excludes extended product warranties.

+ References

+ Details

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- Definition

Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

+ References

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