Changes in Product Support Liabilities (Detail) - Truck, Parts and Other - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024
WARRANTY RESERVES
Beginning balance	$ 606.1	$ 767.0
Cost accruals	442.8	462.2
Payments	(594.8)	(679.5)
Change in estimates for pre-existing warranties	105.6	103.6
Currency translation and other	24.3	2.7
Ending balance	584.0	656.0
DEFERRED REVENUES ON EXTENDED WARRANTIES AND R&M CONTRACTS
Beginning balance	1,302.2	1,229.1
Deferred revenues	543.5	535.0
Revenues recognized	(508.9)	(444.4)
Currency translation	75.9	10.1
Ending balance	$ 1,412.7	$ 1,329.8

Extended product warranty beginning balance.

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- Definition

Extended product warranty currency translation.

+ References

No definition available.

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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.

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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.

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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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