Allowance for Credit Losses (Detail) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2020		Jun. 30, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for losses		$ 24.5		$ 6.2
Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		4.3
Ending Balance		3.5
Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		3.7
Ending Balance		4.5
Financial Services
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		118.6	[1]	113.8
Provision for losses		24.5	[1]	6.2
Charge-offs		(18.5)	[1]	(9.1)
Recoveries		2.5	[1]	7.0
Currency translation and other		(3.6)	[1]	0.6
Ending Balance		123.5	[1]	118.5
Financial Services | Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		4.3		6.8
Provision for losses		(0.7)		(0.1)
Charge-offs				(0.1)
Currency translation and other		(0.1)		(0.1)
Ending Balance		3.5		6.5
Financial Services | Dealer | Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		9.2		10.0
Provision for losses		(0.2)		(0.4)
Currency translation and other		(0.1)		0.1
Ending Balance		8.9		9.7
Financial Services | Customer Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		101.4		93.8
Provision for losses		23.9		5.4
Charge-offs		(17.7)		(8.4)
Recoveries		2.2		6.9
Currency translation and other		(3.2)		0.6
Ending Balance		106.6		98.3
Financial Services | Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	[2]	3.7		3.2
Provision for losses	[2]	1.5		1.3
Charge-offs	[2]	(0.8)		(0.6)
Recoveries	[2]	0.3		0.1
Currency translation and other	[2]	(0.2)
Ending Balance	[2]	$ 4.5		$ 4.0

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

[2] Operating leases and other trade receivables.