Pre- and Post-Modification Recorded Investment Balances for Finance Receivables Modified by Portfolio Class (Detail) - Financial Services - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	$ 1.7	$ 0.6	$ 2.5	$ 8.9
Post-Modification Recorded Investment	1.7	0.6	2.5	8.9
Customer Retail \| Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	1.6	0.5	2.2	8.4
Post-Modification Recorded Investment	1.6	0.5	2.2	8.4
Customer Retail \| Owner/Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	0.1	0.1	0.3	0.5
Post-Modification Recorded Investment	$ 0.1	$ 0.1	$ 0.3	$ 0.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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