Recorded Investment for Finance Receivables that are on Non-accrual Status (Detail) (Financial Services, USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule Of Financing Receivables [Line Items]
Recorded investment of finance receivables that are on non-accrual status	$ 42.1	$ 47.1
Dealer | Wholesale
Schedule Of Financing Receivables [Line Items]
Recorded investment of finance receivables that are on non-accrual status	8.0	8.0
Customer Retail | Fleet
Schedule Of Financing Receivables [Line Items]
Recorded investment of finance receivables that are on non-accrual status	27.2	30.5
Customer Retail | Owner/Operator
Schedule Of Financing Receivables [Line Items]
Recorded investment of finance receivables that are on non-accrual status	$ 6.9	$ 8.6