Changes in Product Support Liabilities (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
WARRANTY RESERVES
Beginning balance	$ 440.0
Ending balance	389.7	$ 440.0
Truck, Parts and Other
WARRANTY RESERVES
Beginning balance	440.0	380.2	$ 298.8
Cost accruals	295.0	386.3	331.9
Payments	(437.2)	(343.7)	(271.8)
Change in estimates for pre-existing warranties	84.1	19.8	25.6
Currency translation and other	7.8	(2.6)	(4.3)
Ending balance	389.7	440.0	380.2
DEFERRED REVENUES ON EXTENDED WARRANTIES AND R&M CONTRACTS
Beginning balance	801.4	699.9	653.9
Deferred revenues	409.9	499.1	448.2
Revenues recognized	(438.9)	(396.4)	(385.0)
Currency translation	23.4	(1.2)	(17.2)
Ending balance	$ 795.8	$ 801.4	$ 699.9

Extended product warranty beginning balance.

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Extended product warranty currency translation.

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Extended product warranty deferred revenues.

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Extended product warranty ending balance.

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Extended product warranty revenues recognized.

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Movement in extended product warranty.

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Standard product warranty accrual currency translation and other.

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

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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Amount of increase (decrease) in the standard product warranty accrual from changes in estimates attributable to preexisting product warranties. Excludes extended product warranties.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties.

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-Publisher FASB
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