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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	$ 1.0	$ 9.5	$ 18.0	$ 26.8
Post-Modification Recorded Investment	1.0	9.5	18.0	26.7
Customer Retail \| Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	0.9	9.1	17.5	23.1
Post-Modification Recorded Investment	0.9	9.1	17.5	23.0
Customer Retail \| Owner/Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	0.1	0.4	0.5	3.7
Post-Modification Recorded Investment	$ 0.1	$ 0.4	$ 0.5	$ 3.7

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

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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