TDRs Modified During Previous Twelve Months that Subsequently Defaulted (Detail) (Financial Services, USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Recorded Investment, subsequently defaulted	$ 0.9	$ 5.3
Customer Retail | Fleet
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Recorded Investment, subsequently defaulted	0.7	4.6
Customer Retail | Owner/Operator
Troubled Debt Restructuring, Debtor, Subsequent Periods [Line Items]
Recorded Investment, subsequently defaulted	$ 0.2	$ 0.7