Recorded Investment for Finance Receivables that are on Non-accrual Status (Detail) - Financial Services - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of finance receivables that are on non-accrual status	$ 77.7	$ 35.5
Dealer | Wholesale
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of finance receivables that are on non-accrual status	24.3	0.1
Dealer | Retail
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of finance receivables that are on non-accrual status	2.3
Customer Retail | Fleet
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of finance receivables that are on non-accrual status	44.3	27.5
Customer Retail | Owner/Operator
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of finance receivables that are on non-accrual status	$ 6.8	$ 7.9