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.

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Segment Reporting Information by Segment (Parenthetical) (Detail) € in Millions, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2016 EUR (€)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
European Commission charge			$ 833.0
Truck, Parts and Other
Segment Reporting Information [Line Items]
European Commission charge	$ 0.0	$ 0.0	$ 833.0	€ 752.7	$ 0.0	$ 833.0