Amount before tax and reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32211-110900

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=118261656&loc=d3e32136-110900

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580

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Pre-Tax Effects of Derivative Instruments Recognized in OCI (Detail) - Derivative Contracts - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest-Rate Contracts
Derivative [Line Items]
(Loss) gain recognized in OCI	$ (49.1)	$ 26.0	$ (27.3)
Foreign-exchange contracts
Derivative [Line Items]
(Loss) gain recognized in OCI	(10.8)	(1.0)	42.6	$ (17.2)
Truck, Parts and Other \| Foreign-exchange contracts
Derivative [Line Items]
(Loss) gain recognized in OCI	(10.8)	(1.0)	42.6	$ (17.2)
Financial Services \| Interest-Rate Contracts
Derivative [Line Items]
(Loss) gain recognized in OCI	$ (49.1)	$ 26.0	$ (27.3)