Allowance for Credit Losses (Detail) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for losses		$ 3.2	$ 27.6
Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		3.4
Ending Balance		2.4
Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		3.2
Ending Balance		3.4
Financial Services
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		127.0	118.6	[1]
Provision for losses		3.2	27.6	[1]
Charge-offs		(11.0)	(23.5)	[1]
Recoveries		4.3	4.0	[1]
Currency translation and other		(1.8)	(2.0)	[1]
Ending Balance		121.7	124.7	[1]
Financial Services | Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		3.4	4.3
Provision for losses		(1.0)	(1.1)
Ending Balance		2.4	3.2
Financial Services | Dealer | Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		8.4	9.2
Provision for losses		(0.7)	(0.8)
Ending Balance		7.7	8.4
Financial Services | Customer Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		112.0	101.4
Provision for losses		3.5	28.5
Charge-offs		(9.7)	(22.3)
Recoveries		4.1	3.6
Currency translation and other		(1.7)	(1.8)
Ending Balance		108.2	109.4
Financial Services | Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	[2]	3.2	3.7
Provision for losses	[2]	1.4	1.0
Charge-offs	[2]	(1.3)	(1.2)
Recoveries	[2]	0.2	0.4
Currency translation and other	[2]	(0.1)	(0.2)
Ending Balance	[2]	$ 3.4	$ 3.7

[1] The beginning balance has been adjusted for the adoption of ASU 2016-13.

[2] Operating leases and other trade receivables.