Pre- and Post-Modification Recorded Investment Balances for Finance Receivables Modified by Portfolio Class (Detail) - Financial Services - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	$ 2.5	$ 13.1
Post-Modification Recorded Investment	2.5	13.1
Customer Retail \| Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	2.2	12.1
Post-Modification Recorded Investment	2.2	12.1
Customer Retail \| Owner/Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	0.3	1.0
Post-Modification Recorded Investment	$ 0.3	$ 1.0

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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