Pre- and Post-Modification Amortized Cost Basis Balances for Finance Receivables Modified by Portfolio Class (Detail) - Financial Services - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Modifications [Line Items]
Pre-Modification, Amortized Cost Basis	$ 7.5	$ 0.3	$ 8.1	$ 5.8
Post-Modification, Amortized Cost Basis	7.5	0.3	8.1	5.7
Customer Retail | Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification, Amortized Cost Basis	7.5	0.2	8.1	4.8
Post-Modification, Amortized Cost Basis	$ 7.5	0.2	$ 8.1	4.7
Customer Retail | Owner/Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification, Amortized Cost Basis		0.1		1.0
Post-Modification, Amortized Cost Basis		$ 0.1		$ 1.0