Allowance for Credit Losses (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020		Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for losses		$ 28.8		$ 15.4	$ 16.5
Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		4.3
Ending Balance		3.4		4.3
Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		3.7
Ending Balance		3.2		3.7
Financial Services
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		112.4		113.8	117.2
Provision for losses		28.8	[1]	15.4	16.5
Charge-offs		(28.0)	[1]	(28.4)	(27.5)
Recoveries		5.7	[1]	11.0	10.3
Currency translation and other		1.9	[1]	0.6	(2.7)
Ending Balance		127.0	[1]	112.4	113.8
Financial Services | ASU 2016-13
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	[1]	118.6
Ending Balance	[1]			118.6
Financial Services | Dealer | Wholesale
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		4.3		6.8	6.0
Provision for losses		(1.0)		(1.6)	1.0
Charge-offs				(0.6)
Currency translation and other		0.1		(0.3)	(0.2)
Ending Balance		3.4		4.3	6.8
Financial Services | Dealer | Wholesale | ASU 2016-13
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		4.3
Ending Balance				4.3
Financial Services | Dealer | Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		9.2		10.0	9.4
Provision for losses		(0.8)		(1.0)	0.7
Currency translation and other				0.2	(0.1)
Ending Balance		8.4		9.2	10.0
Financial Services | Dealer | Retail | ASU 2016-13
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		9.2
Ending Balance				9.2
Financial Services | Customer Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		95.2		93.8	92.5
Provision for losses		30.1		14.2	13.6
Charge-offs		(26.6)		(24.2)	(20.0)
Recoveries		5.3		10.7	9.9
Currency translation and other		1.8		0.7	(2.2)
Ending Balance		112.0		95.2	93.8
Financial Services | Customer Retail | ASU 2016-13
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance		101.4
Ending Balance				101.4
Financial Services | Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	[2]	3.7		3.2	9.3
Provision for losses	[2]	0.5		3.8	1.2
Charge-offs	[2]	(1.4)		(3.6)	(7.5)
Recoveries	[2]	0.4		0.3	0.4
Currency translation and other	[2]				(0.2)
Ending Balance	[2]	3.2		3.7	$ 3.2
Financial Services | Other | ASU 2016-13
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	[2]	$ 3.7
Ending Balance	[2]			$ 3.7

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

[2] Operating lease and other trade receivables.