Amortized Cost Basis of Finance Receivables Modified by Portfolio Class (Detail) - Customer Retail - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable Modifications [Line Items]
Amortized cost basis of finance receivables	$ 5.2	$ 6.0
Financing receivable modifications percentage	0.20%	0.20%
Fleet
Financing Receivable Modifications [Line Items]
Amortized cost basis of finance receivables	$ 5.1	$ 6.0
Owner/Operator
Financing Receivable Modifications [Line Items]
Amortized cost basis of finance receivables	$ 0.1