Pre-Modification and Post-Modification Amortized Cost Basis (Detail) - Customer Retail $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)
Financing Receivable, Modifications [Line Items]
Pre-Modification Amortized cost basis	$ 0.8
Post-Modification Amortized cost basis	0.7
Fleet
Financing Receivable, Modifications [Line Items]
Pre-Modification Amortized cost basis	0.7
Post-Modification Amortized cost basis	0.6
Owner Operator
Financing Receivable, Modifications [Line Items]
Pre-Modification Amortized cost basis	0.1
Post-Modification Amortized cost basis	$ 0.1