Interest Income Recognized on Cash Basis (Detail) - Financial Services - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Interest income recognized:
Interest income recognized on a cash basis	$ 0.2	$ 0.5	$ 0.6	$ 1.5
Customer Retail | Fleet
Interest income recognized:
Interest income recognized on a cash basis	$ 0.2	0.4	$ 0.6	1.2
Customer Retail | Owner/Operator
Interest income recognized:
Interest income recognized on a cash basis		$ 0.1		0.2
Dealer | Retail
Interest income recognized:
Interest income recognized on a cash basis				$ 0.1