Pre- and Post-Modification Amortized Cost Basis Balances for Finance Receivables Modified by Portfolio Class (Detail) - Financial Services - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Financing Receivable, Modifications [Line Items]
2022	$ 0.6	$ 5.5
2022	0.6	5.4
Customer Retail | Fleet
Financing Receivable, Modifications [Line Items]
2022	0.6	4.6
2022	$ 0.6	4.5
Customer Retail | Owner/Operator
Financing Receivable, Modifications [Line Items]
2022		0.9
2022		$ 0.9