Segment and Related Information - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2024 USD ($) Segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Segment Reporting Information [Line Items]
Reportable segments \| Segment	3
Investment (expenses) income	$ 394.7	$ 292.2	$ 61.0
Financial Services \| Intersegment \| Cash Advances
Segment Reporting Information [Line Items]
Investment (expenses) income	13.6	12.4	(1.9)
Financial Services \| Wholesale \| Intersegment \| Dealer
Segment Reporting Information [Line Items]
Interest (expense) income	$ (80.9)	$ (91.2)	$ (44.6)

Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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