Allowance for Credit Losses (Detail) (Financial Services, USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	$ 139.0		$ 145.0
Provision for losses	15.2		32.2
Charge-offs	(21.9)		(39.3)
Recoveries	5.0		7.8
Currency translation	1.8		(2.3)
Ending Balance	139.1		143.4
Dealer wholesale financing
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	11.7		7.5
Provision for losses	2.3		4.4
Charge-offs			(1.0)
Recoveries	0.1
Currency translation	(1.7)		(0.1)
Ending Balance	12.4		10.8
Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	118.5		131.5
Provision for losses	10.5		17.1
Charge-offs	(17.1)		(29.6)
Recoveries	4.6		7.0
Currency translation	4.1		(2.9)
Ending Balance	120.6		123.1
Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	8.8	[1]	6.0	[1]
Provision for losses	2.4	[1]	10.7	[1]
Charge-offs	(4.8)	[1]	(8.7)	[1]
Recoveries	0.3	[1]	0.8	[1]
Currency translation	(0.6)	[1]	0.7	[1]
Ending Balance	$ 6.1	[1]	$ 9.5	[1]

[1] Accrued rents and other trade receivables.