Pre- and Post-Modification Recorded Investment Balances for Finance Receivables Modified by Portfolio Class (Detail) (Financial Services, USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	$ 19.1	$ 2.2	$ 25.8	$ 10.6
Post-Modification Recorded Investment	18.9	2.0	25.6	10.3
Customer Retail | Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	18.7	1.5	24.1	9.2
Post-Modification Recorded Investment	18.5	1.3	23.9	8.9
Customer Retail | Owner/Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	0.4	0.7	1.7	1.4
Post-Modification Recorded Investment	$ 0.4	$ 0.7	$ 1.7	$ 1.4