Valuation Accounts and Reserves (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Allowance for Doubtful Accounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 7.9		$ 8.0		$ 7.8
Charged (Credited) to Expense	0.3		0.2		0.5
Deductions	(1.5)		(0.3)		(0.2)
Other	0	[1]	0	[1]	(0.1)	[1]
Ending Balance	6.7		7.9		8.0
Deferred tax asset valuation allowance
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	445.8		305.3		290.2
Charged (Credited) to Expense	78.2		140.5		15.1
Deductions	0		0		0
Other	0	[1]	0	[1]	0	[1]
Ending Balance	$ 524.0		$ 445.8		$ 305.3

[1] Amounts primarily represent changes in foreign currency exchange rates.