Summary of Impaired Loans and Specific Reserve (Cash Basis Method) (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
Interest income recognized:
Interest income recognized on a cash basis	$ 0.4	$ 0.5	$ 1.3	$ 2.3
Dealer | Wholesale
Interest income recognized:
Interest income recognized on a cash basis			0.1	0.1
Customer Retail | Fleet
Interest income recognized:
Interest income recognized on a cash basis	0.3	0.5	0.9	1.8
Customer Retail | Owner/Operator
Interest income recognized:
Interest income recognized on a cash basis	$ 0.1		$ 0.3	$ 0.4