Income Taxes (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Feb. 29, 2012 2007 Tax Year [Member] Brazil [Member]
Income Taxes [Line Items]
Total tax assessment including interest and penalty	$ 17.0	$ 35.1
Reversal of accrual for uncertain tax positions, total	4.4
Reversal of Penalty Related to Uncertain Tax Position	0.2
Reversal Of Interest Accrual Related To Uncertain Tax Position	$ 2.6