Interest Income Recognized on Cash Basis (Detail) - Financial Services - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income recognized:
Interest income recognized on a cash basis	$ 1.9	$ 1.7	$ 2.2
Dealer | Retail
Interest income recognized:
Interest income recognized on a cash basis	0.2	0.2
Customer Retail | Fleet
Interest income recognized:
Interest income recognized on a cash basis	1.5	1.3	2.0
Customer Retail | Owner/Operator
Interest income recognized:
Interest income recognized on a cash basis	$ 0.2	$ 0.2	$ 0.2